src/kitemviews/kitemlistview.cpp

   1 /*
   2  * SPDX-FileCopyrightText: 2011 Peter Penz <peter.penz19@gmail.com>
   3  *
   4  * Based on the Itemviews NG project from Trolltech Labs
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-or-later
   7  */
   8
   9 #include "kitemlistview.h"
  10
  11 #include "dolphindebug.h"
  12 #include "kitemlistcontainer.h"
  13 #include "kitemlistcontroller.h"
  14 #include "kitemlistheader.h"
  15 #include "kitemlistselectionmanager.h"
  16 #include "kitemlistviewaccessible.h"
  17 #include "kstandarditemlistwidget.h"
  18
  19 #include "private/kitemlistheaderwidget.h"
  20 #include "private/kitemlistrubberband.h"
  21 #include "private/kitemlistsizehintresolver.h"
  22 #include "private/kitemlistviewlayouter.h"
  23
  24 #include <QElapsedTimer>
  25 #include <QGraphicsSceneMouseEvent>
  26 #include <QGraphicsView>
  27 #include <QPropertyAnimation>
  28 #include <QStyleOptionRubberBand>
  29 #include <QTimer>
  30 #include <QVariantAnimation>
  31
  32
  33 namespace {
  34     // Time in ms until reaching the autoscroll margin triggers
  35     // an initial autoscrolling
  36     const int InitialAutoScrollDelay = 700;
  37
  38     // Delay in ms for triggering the next autoscroll
  39     const int RepeatingAutoScrollDelay = 1000 / 60;
  40
  41     // Copied from the Kirigami.Units.shortDuration
  42     const int RubberFadeSpeed = 150;
  43
  44     const char* RubberPropertyName = "_kitemviews_rubberBandPosition";
  45 }
  46
  47 #ifndef QT_NO_ACCESSIBILITY
  48 QAccessibleInterface* accessibleInterfaceFactory(const QString& key, QObject* object)
  49 {
  50     Q_UNUSED(key)
  51
  52     if (KItemListContainer* container = qobject_cast<KItemListContainer*>(object)) {
  53         return new KItemListContainerAccessible(container);
  54     } else if (KItemListView* view = qobject_cast<KItemListView*>(object)) {
  55         return new KItemListViewAccessible(view);
  56     }
  57
  58     return nullptr;
  59 }
  60 #endif
  61
  62 KItemListView::KItemListView(QGraphicsWidget* parent) :
  63     QGraphicsWidget(parent),
  64     m_enabledSelectionToggles(false),
  65     m_grouped(false),
  66     m_supportsItemExpanding(false),
  67     m_editingRole(false),
  68     m_activeTransactions(0),
  69     m_endTransactionAnimationHint(Animation),
  70     m_itemSize(),
  71     m_controller(nullptr),
  72     m_model(nullptr),
  73     m_visibleRoles(),
  74     m_widgetCreator(nullptr),
  75     m_groupHeaderCreator(nullptr),
  76     m_styleOption(),
  77     m_visibleItems(),
  78     m_visibleGroups(),
  79     m_visibleCells(),
  80     m_sizeHintResolver(nullptr),
  81     m_layouter(nullptr),
  82     m_animation(nullptr),
  83     m_oldScrollOffset(0),
  84     m_oldMaximumScrollOffset(0),
  85     m_oldItemOffset(0),
  86     m_oldMaximumItemOffset(0),
  87     m_skipAutoScrollForRubberBand(false),
  88     m_rubberBand(nullptr),
  89     m_tapAndHoldIndicator(nullptr),
  90     m_mousePos(),
  91     m_autoScrollIncrement(0),
  92     m_autoScrollTimer(nullptr),
  93     m_header(nullptr),
  94     m_headerWidget(nullptr),
  95     m_indicatorAnimation(nullptr),
  96     m_dropIndicator()
  97 {
  98     setAcceptHoverEvents(true);
  99     setAcceptTouchEvents(true);
 100
 101     m_sizeHintResolver = new KItemListSizeHintResolver(this);
 102
 103     m_layouter = new KItemListViewLayouter(m_sizeHintResolver, this);
 104
 105     m_animation = new KItemListViewAnimation(this);
 106     connect(m_animation, &KItemListViewAnimation::finished,
 107             this, &KItemListView::slotAnimationFinished);
 108
 109     m_rubberBand = new KItemListRubberBand(this);
 110     connect(m_rubberBand, &KItemListRubberBand::activationChanged, this, &KItemListView::slotRubberBandActivationChanged);
 111
 112     m_tapAndHoldIndicator = new KItemListRubberBand(this);
 113     m_indicatorAnimation = new QPropertyAnimation(m_tapAndHoldIndicator, "endPosition", this);
 114     connect(m_tapAndHoldIndicator, &KItemListRubberBand::activationChanged, this, [this](bool active) {
 115         if (active) {
 116             m_indicatorAnimation->setDuration(150);
 117             m_indicatorAnimation->setStartValue(QPointF(1, 1));
 118             m_indicatorAnimation->setEndValue(QPointF(40, 40));
 119             m_indicatorAnimation->start();
 120         }
 121         update();
 122     });
 123     connect(m_tapAndHoldIndicator, &KItemListRubberBand::endPositionChanged, this, [this]() {
 124         if (m_tapAndHoldIndicator->isActive()) {
 125             update();
 126         }
 127     });
 128
 129     m_headerWidget = new KItemListHeaderWidget(this);
 130     m_headerWidget->setVisible(false);
 131
 132     m_header = new KItemListHeader(this);
 133
 134 #ifndef QT_NO_ACCESSIBILITY
 135     QAccessible::installFactory(accessibleInterfaceFactory);
 136 #endif
 137
 138 }
 139
 140 KItemListView::~KItemListView()
 141 {
 142     // The group headers are children of the widgets created by
 143     // widgetCreator(). So it is mandatory to delete the group headers
 144     // first.
 145     delete m_groupHeaderCreator;
 146     m_groupHeaderCreator = nullptr;
 147
 148     delete m_widgetCreator;
 149     m_widgetCreator = nullptr;
 150
 151     delete m_sizeHintResolver;
 152     m_sizeHintResolver = nullptr;
 153 }
 154
 155 void KItemListView::setScrollOffset(qreal offset)
 156 {
 157     if (offset < 0) {
 158         offset = 0;
 159     }
 160
 161     const qreal previousOffset = m_layouter->scrollOffset();
 162     if (offset == previousOffset) {
 163         return;
 164     }
 165
 166     m_layouter->setScrollOffset(offset);
 167     m_animation->setScrollOffset(offset);
 168
 169     // Don't check whether the m_layoutTimer is active: Changing the
 170     // scroll offset must always trigger a synchronous layout, otherwise
 171     // the smooth-scrolling might get jerky.
 172     doLayout(NoAnimation);
 173     onScrollOffsetChanged(offset, previousOffset);
 174 }
 175
 176 qreal KItemListView::scrollOffset() const
 177 {
 178     return m_layouter->scrollOffset();
 179 }
 180
 181 qreal KItemListView::maximumScrollOffset() const
 182 {
 183     return m_layouter->maximumScrollOffset();
 184 }
 185
 186 void KItemListView::setItemOffset(qreal offset)
 187 {
 188     if (m_layouter->itemOffset() == offset) {
 189         return;
 190     }
 191
 192     m_layouter->setItemOffset(offset);
 193     if (m_headerWidget->isVisible()) {
 194         m_headerWidget->setOffset(offset);
 195     }
 196
 197     // Don't check whether the m_layoutTimer is active: Changing the
 198     // item offset must always trigger a synchronous layout, otherwise
 199     // the smooth-scrolling might get jerky.
 200     doLayout(NoAnimation);
 201 }
 202
 203 qreal KItemListView::itemOffset() const
 204 {
 205     return m_layouter->itemOffset();
 206 }
 207
 208 qreal KItemListView::maximumItemOffset() const
 209 {
 210     return m_layouter->maximumItemOffset();
 211 }
 212
 213 int KItemListView::maximumVisibleItems() const
 214 {
 215     return m_layouter->maximumVisibleItems();
 216 }
 217
 218 void KItemListView::setVisibleRoles(const QList<QByteArray>& roles)
 219 {
 220     const QList<QByteArray> previousRoles = m_visibleRoles;
 221     m_visibleRoles = roles;
 222     onVisibleRolesChanged(roles, previousRoles);
 223
 224     m_sizeHintResolver->clearCache();
 225     m_layouter->markAsDirty();
 226
 227     if (m_itemSize.isEmpty()) {
 228         m_headerWidget->setColumns(roles);
 229         updatePreferredColumnWidths();
 230         if (!m_headerWidget->automaticColumnResizing()) {
 231             // The column-width of new roles are still 0. Apply the preferred
 232             // column-width as default with.
 233             for (const QByteArray& role : qAsConst(m_visibleRoles)) {
 234                 if (m_headerWidget->columnWidth(role) == 0) {
 235                     const qreal width = m_headerWidget->preferredColumnWidth(role);
 236                     m_headerWidget->setColumnWidth(role, width);
 237                 }
 238             }
 239
 240             applyColumnWidthsFromHeader();
 241         }
 242     }
 243
 244     const bool alternateBackgroundsChanged = m_itemSize.isEmpty() &&
 245                                              ((roles.count() > 1 && previousRoles.count() <= 1) ||
 246                                               (roles.count() <= 1 && previousRoles.count() > 1));
 247
 248     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 249     while (it.hasNext()) {
 250         it.next();
 251         KItemListWidget* widget = it.value();
 252         widget->setVisibleRoles(roles);
 253         if (alternateBackgroundsChanged) {
 254             updateAlternateBackgroundForWidget(widget);
 255         }
 256     }
 257
 258     doLayout(NoAnimation);
 259 }
 260
 261 QList<QByteArray> KItemListView::visibleRoles() const
 262 {
 263     return m_visibleRoles;
 264 }
 265
 266 void KItemListView::setAutoScroll(bool enabled)
 267 {
 268     if (enabled && !m_autoScrollTimer) {
 269         m_autoScrollTimer = new QTimer(this);
 270         m_autoScrollTimer->setSingleShot(true);
 271         connect(m_autoScrollTimer, &QTimer::timeout, this, &KItemListView::triggerAutoScrolling);
 272         m_autoScrollTimer->start(InitialAutoScrollDelay);
 273     } else if (!enabled && m_autoScrollTimer) {
 274         delete m_autoScrollTimer;
 275         m_autoScrollTimer = nullptr;
 276     }
 277 }
 278
 279 bool KItemListView::autoScroll() const
 280 {
 281     return m_autoScrollTimer != nullptr;
 282 }
 283
 284 void KItemListView::setEnabledSelectionToggles(bool enabled)
 285 {
 286     if (m_enabledSelectionToggles != enabled) {
 287         m_enabledSelectionToggles = enabled;
 288
 289         QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 290         while (it.hasNext()) {
 291             it.next();
 292             it.value()->setEnabledSelectionToggle(enabled);
 293         }
 294     }
 295 }
 296
 297 bool KItemListView::enabledSelectionToggles() const
 298 {
 299     return m_enabledSelectionToggles;
 300 }
 301
 302 KItemListController* KItemListView::controller() const
 303 {
 304     return m_controller;
 305 }
 306
 307 KItemModelBase* KItemListView::model() const
 308 {
 309     return m_model;
 310 }
 311
 312 void KItemListView::setWidgetCreator(KItemListWidgetCreatorBase* widgetCreator)
 313 {
 314     delete m_widgetCreator;
 315     m_widgetCreator = widgetCreator;
 316 }
 317
 318 KItemListWidgetCreatorBase* KItemListView::widgetCreator() const
 319 {
 320     if (!m_widgetCreator) {
 321         m_widgetCreator = defaultWidgetCreator();
 322     }
 323     return m_widgetCreator;
 324 }
 325
 326 void KItemListView::setGroupHeaderCreator(KItemListGroupHeaderCreatorBase* groupHeaderCreator)
 327 {
 328     delete m_groupHeaderCreator;
 329     m_groupHeaderCreator = groupHeaderCreator;
 330 }
 331
 332 KItemListGroupHeaderCreatorBase* KItemListView::groupHeaderCreator() const
 333 {
 334     if (!m_groupHeaderCreator) {
 335         m_groupHeaderCreator = defaultGroupHeaderCreator();
 336     }
 337     return m_groupHeaderCreator;
 338 }
 339
 340 QSizeF KItemListView::itemSize() const
 341 {
 342     return m_itemSize;
 343 }
 344
 345 const KItemListStyleOption& KItemListView::styleOption() const
 346 {
 347     return m_styleOption;
 348 }
 349
 350 void KItemListView::setGeometry(const QRectF& rect)
 351 {
 352     QGraphicsWidget::setGeometry(rect);
 353
 354     if (!m_model) {
 355         return;
 356     }
 357
 358     const QSizeF newSize = rect.size();
 359     if (m_itemSize.isEmpty()) {
 360         m_headerWidget->resize(rect.width(), m_headerWidget->size().height());
 361         if (m_headerWidget->automaticColumnResizing()) {
 362             applyAutomaticColumnWidths();
 363         } else {
 364             const qreal requiredWidth = columnWidthsSum();
 365             const QSizeF dynamicItemSize(qMax(newSize.width(), requiredWidth),
 366                                          m_itemSize.height());
 367             m_layouter->setItemSize(dynamicItemSize);
 368         }
 369     }
 370
 371     m_layouter->setSize(newSize);
 372     // We don't animate the moving of the items here because
 373     // it would look like the items are slow to find their position.
 374     doLayout(NoAnimation);
 375 }
 376
 377 qreal KItemListView::verticalPageStep() const
 378 {
 379     qreal headerHeight = 0;
 380     if (m_headerWidget->isVisible()) {
 381         headerHeight = m_headerWidget->size().height();
 382     }
 383     return size().height() - headerHeight;
 384 }
 385
 386 std::optional<int> KItemListView::itemAt(const QPointF& pos) const
 387 {
 388     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 389     while (it.hasNext()) {
 390         it.next();
 391
 392         const KItemListWidget* widget = it.value();
 393         const QPointF mappedPos = widget->mapFromItem(this, pos);
 394         if (widget->contains(mappedPos) || widget->selectionRect().contains(mappedPos)) {
 395             return it.key();
 396         }
 397     }
 398
 399     return std::nullopt;
 400 }
 401
 402 bool KItemListView::isAboveSelectionToggle(int index, const QPointF& pos) const
 403 {
 404     if (!m_enabledSelectionToggles) {
 405         return false;
 406     }
 407
 408     const KItemListWidget* widget = m_visibleItems.value(index);
 409     if (widget) {
 410         const QRectF selectionToggleRect = widget->selectionToggleRect();
 411         if (!selectionToggleRect.isEmpty()) {
 412             const QPointF mappedPos = widget->mapFromItem(this, pos);
 413             return selectionToggleRect.contains(mappedPos);
 414         }
 415     }
 416     return false;
 417 }
 418
 419 bool KItemListView::isAboveExpansionToggle(int index, const QPointF& pos) const
 420 {
 421     const KItemListWidget* widget = m_visibleItems.value(index);
 422     if (widget) {
 423         const QRectF expansionToggleRect = widget->expansionToggleRect();
 424         if (!expansionToggleRect.isEmpty()) {
 425             const QPointF mappedPos = widget->mapFromItem(this, pos);
 426             return expansionToggleRect.contains(mappedPos);
 427         }
 428     }
 429     return false;
 430 }
 431
 432 bool KItemListView::isAboveText(int index, const QPointF &pos) const
 433 {
 434     const KItemListWidget* widget = m_visibleItems.value(index);
 435     if (widget) {
 436         const QRectF &textRect = widget->textRect();
 437         if (!textRect.isEmpty()) {
 438             const QPointF mappedPos = widget->mapFromItem(this, pos);
 439             return textRect.contains(mappedPos);
 440         }
 441     }
 442     return false;
 443 }
 444
 445 int KItemListView::firstVisibleIndex() const
 446 {
 447     return m_layouter->firstVisibleIndex();
 448 }
 449
 450 int KItemListView::lastVisibleIndex() const
 451 {
 452     return m_layouter->lastVisibleIndex();
 453 }
 454
 455 void KItemListView::calculateItemSizeHints(QVector<std::pair<qreal, bool>>& logicalHeightHints, qreal& logicalWidthHint) const
 456 {
 457     widgetCreator()->calculateItemSizeHints(logicalHeightHints, logicalWidthHint, this);
 458 }
 459
 460 void KItemListView::setSupportsItemExpanding(bool supportsExpanding)
 461 {
 462     if (m_supportsItemExpanding != supportsExpanding) {
 463         m_supportsItemExpanding = supportsExpanding;
 464         updateSiblingsInformation();
 465         onSupportsItemExpandingChanged(supportsExpanding);
 466     }
 467 }
 468
 469 bool KItemListView::supportsItemExpanding() const
 470 {
 471     return m_supportsItemExpanding;
 472 }
 473
 474 void KItemListView::setHighlightEntireRow(bool highlightEntireRow)
 475 {
 476     if (m_highlightEntireRow != highlightEntireRow) {
 477         m_highlightEntireRow = highlightEntireRow;
 478         onHighlightEntireRowChanged(highlightEntireRow);
 479     }
 480 }
 481
 482 bool KItemListView::highlightEntireRow() const
 483 {
 484     return m_highlightEntireRow;
 485 }
 486
 487 void KItemListView::setAlternateBackgrounds(bool alternate)
 488 {
 489     if (m_alternateBackgrounds != alternate) {
 490         m_alternateBackgrounds = alternate;
 491         updateAlternateBackgrounds();
 492     }
 493 }
 494
 495 bool KItemListView::alternateBackgrounds() const
 496 {
 497     return m_alternateBackgrounds;
 498 }
 499
 500 QRectF KItemListView::itemRect(int index) const
 501 {
 502     return m_layouter->itemRect(index);
 503 }
 504
 505 QRectF KItemListView::itemContextRect(int index) const
 506 {
 507     QRectF contextRect;
 508
 509     const KItemListWidget* widget = m_visibleItems.value(index);
 510     if (widget) {
 511         contextRect = widget->iconRect() | widget->textRect();
 512         contextRect.translate(itemRect(index).topLeft());
 513     }
 514
 515     return contextRect;
 516 }
 517
 518 bool KItemListView::isElided(int index) const
 519 {
 520     return m_sizeHintResolver->isElided(index);
 521 }
 522
 523 void KItemListView::scrollToItem(int index)
 524 {
 525     QRectF viewGeometry = geometry();
 526     if (m_headerWidget->isVisible()) {
 527         const qreal headerHeight = m_headerWidget->size().height();
 528         viewGeometry.adjust(0, headerHeight, 0, 0);
 529     }
 530     QRectF currentRect = itemRect(index);
 531
 532     // Fix for Bug 311099 - View the underscore when using Ctrl + PagDown
 533     currentRect.adjust(-m_styleOption.horizontalMargin, -m_styleOption.verticalMargin,
 534                         m_styleOption.horizontalMargin,  m_styleOption.verticalMargin);
 535
 536     if (!viewGeometry.contains(currentRect)) {
 537         qreal newOffset = scrollOffset();
 538         if (scrollOrientation() == Qt::Vertical) {
 539             if (currentRect.top() < viewGeometry.top()) {
 540                 newOffset += currentRect.top() - viewGeometry.top();
 541             } else if (currentRect.bottom() > viewGeometry.bottom()) {
 542                 newOffset += currentRect.bottom() - viewGeometry.bottom();
 543             }
 544         } else {
 545             if (currentRect.left() < viewGeometry.left()) {
 546                 newOffset += currentRect.left() - viewGeometry.left();
 547             } else if (currentRect.right() > viewGeometry.right()) {
 548                 newOffset += currentRect.right() - viewGeometry.right();
 549             }
 550         }
 551
 552         if (newOffset != scrollOffset()) {
 553             Q_EMIT scrollTo(newOffset);
 554             return;
 555         }
 556     }
 557
 558     Q_EMIT scrollingStopped();
 559 }
 560
 561 void KItemListView::beginTransaction()
 562 {
 563     ++m_activeTransactions;
 564     if (m_activeTransactions == 1) {
 565         onTransactionBegin();
 566     }
 567 }
 568
 569 void KItemListView::endTransaction()
 570 {
 571     --m_activeTransactions;
 572     if (m_activeTransactions < 0) {
 573         m_activeTransactions = 0;
 574         qCWarning(DolphinDebug) << "Mismatch between beginTransaction()/endTransaction()";
 575     }
 576
 577     if (m_activeTransactions == 0) {
 578         onTransactionEnd();
 579         doLayout(m_endTransactionAnimationHint);
 580         m_endTransactionAnimationHint = Animation;
 581     }
 582 }
 583
 584 bool KItemListView::isTransactionActive() const
 585 {
 586     return m_activeTransactions > 0;
 587 }
 588
 589 void KItemListView::setHeaderVisible(bool visible)
 590 {
 591     if (visible && !m_headerWidget->isVisible()) {
 592         QStyleOptionHeader option;
 593         const QSize headerSize = style()->sizeFromContents(QStyle::CT_HeaderSection,
 594                                                            &option, QSize());
 595
 596         m_headerWidget->setPos(0, 0);
 597         m_headerWidget->resize(size().width(), headerSize.height());
 598         m_headerWidget->setModel(m_model);
 599         m_headerWidget->setColumns(m_visibleRoles);
 600         m_headerWidget->setZValue(1);
 601
 602         connect(m_headerWidget, &KItemListHeaderWidget::columnWidthChanged,
 603                 this, &KItemListView::slotHeaderColumnWidthChanged);
 604         connect(m_headerWidget, &KItemListHeaderWidget::leadingPaddingChanged,
 605                 this, &KItemListView::slotLeadingPaddingChanged);
 606         connect(m_headerWidget, &KItemListHeaderWidget::columnMoved,
 607                 this, &KItemListView::slotHeaderColumnMoved);
 608         connect(m_headerWidget, &KItemListHeaderWidget::sortOrderChanged,
 609                 this, &KItemListView::sortOrderChanged);
 610         connect(m_headerWidget, &KItemListHeaderWidget::sortRoleChanged,
 611                 this, &KItemListView::sortRoleChanged);
 612
 613         m_layouter->setHeaderHeight(headerSize.height());
 614         m_headerWidget->setVisible(true);
 615     } else if (!visible && m_headerWidget->isVisible()) {
 616         disconnect(m_headerWidget, &KItemListHeaderWidget::columnWidthChanged,
 617                    this, &KItemListView::slotHeaderColumnWidthChanged);
 618         disconnect(m_headerWidget, &KItemListHeaderWidget::leadingPaddingChanged,
 619                 this, &KItemListView::slotLeadingPaddingChanged);
 620         disconnect(m_headerWidget, &KItemListHeaderWidget::columnMoved,
 621                    this, &KItemListView::slotHeaderColumnMoved);
 622         disconnect(m_headerWidget, &KItemListHeaderWidget::sortOrderChanged,
 623                    this, &KItemListView::sortOrderChanged);
 624         disconnect(m_headerWidget, &KItemListHeaderWidget::sortRoleChanged,
 625                    this, &KItemListView::sortRoleChanged);
 626
 627         m_layouter->setHeaderHeight(0);
 628         m_headerWidget->setVisible(false);
 629     }
 630 }
 631
 632 bool KItemListView::isHeaderVisible() const
 633 {
 634     return m_headerWidget->isVisible();
 635 }
 636
 637 KItemListHeader* KItemListView::header() const
 638 {
 639     return m_header;
 640 }
 641
 642 QPixmap KItemListView::createDragPixmap(const KItemSet& indexes) const
 643 {
 644     QPixmap pixmap;
 645
 646     if (indexes.count() == 1) {
 647         KItemListWidget* item = m_visibleItems.value(indexes.first());
 648         QGraphicsView* graphicsView = scene()->views()[0];
 649         if (item && graphicsView) {
 650             pixmap = item->createDragPixmap(nullptr, graphicsView);
 651         }
 652     } else {
 653         // TODO: Not implemented yet. Probably extend the interface
 654         // from KItemListWidget::createDragPixmap() to return a pixmap
 655         // that can be used for multiple indexes.
 656     }
 657
 658     return pixmap;
 659 }
 660
 661 void KItemListView::editRole(int index, const QByteArray& role)
 662 {
 663     KStandardItemListWidget* widget = qobject_cast<KStandardItemListWidget *>(m_visibleItems.value(index));
 664     if (!widget || m_editingRole) {
 665         return;
 666     }
 667
 668     m_editingRole = true;
 669     widget->setEditedRole(role);
 670
 671     connect(widget, &KItemListWidget::roleEditingCanceled,
 672             this, &KItemListView::slotRoleEditingCanceled);
 673     connect(widget, &KItemListWidget::roleEditingFinished,
 674             this, &KItemListView::slotRoleEditingFinished);
 675
 676     connect(this, &KItemListView::scrollOffsetChanged,
 677             widget, &KStandardItemListWidget::finishRoleEditing);
 678 }
 679
 680 void KItemListView::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget)
 681 {
 682     QGraphicsWidget::paint(painter, option, widget);
 683
 684     for (auto animation : qAsConst(m_rubberBandAnimations)) {
 685         QRectF rubberBandRect = animation->property(RubberPropertyName).toRectF();
 686
 687         const QPointF topLeft = rubberBandRect.topLeft();
 688         if (scrollOrientation() == Qt::Vertical) {
 689             rubberBandRect.moveTo(topLeft.x(), topLeft.y() - scrollOffset());
 690         } else {
 691             rubberBandRect.moveTo(topLeft.x() - scrollOffset(), topLeft.y());
 692         }
 693
 694         QStyleOptionRubberBand opt;
 695         initStyleOption(&opt);
 696         opt.shape = QRubberBand::Rectangle;
 697         opt.opaque = false;
 698         opt.rect = rubberBandRect.toRect();
 699
 700         painter->save();
 701
 702         painter->setOpacity(animation->currentValue().toReal());
 703         style()->drawControl(QStyle::CE_RubberBand, &opt, painter);
 704
 705         painter->restore();
 706     }
 707
 708     if (m_rubberBand->isActive()) {
 709         QRectF rubberBandRect = QRectF(m_rubberBand->startPosition(),
 710                                        m_rubberBand->endPosition()).normalized();
 711
 712         const QPointF topLeft = rubberBandRect.topLeft();
 713         if (scrollOrientation() == Qt::Vertical) {
 714             rubberBandRect.moveTo(topLeft.x(), topLeft.y() - scrollOffset());
 715         } else {
 716             rubberBandRect.moveTo(topLeft.x() - scrollOffset(), topLeft.y());
 717         }
 718
 719         QStyleOptionRubberBand opt;
 720         initStyleOption(&opt);
 721         opt.shape = QRubberBand::Rectangle;
 722         opt.opaque = false;
 723         opt.rect = rubberBandRect.toRect();
 724         style()->drawControl(QStyle::CE_RubberBand, &opt, painter);
 725     }
 726
 727     if (m_tapAndHoldIndicator->isActive()) {
 728         const QPointF indicatorSize = m_tapAndHoldIndicator->endPosition();
 729         const QRectF rubberBandRect = QRectF(m_tapAndHoldIndicator->startPosition() - indicatorSize,
 730                                     (m_tapAndHoldIndicator->startPosition()) + indicatorSize).normalized();
 731         QStyleOptionRubberBand opt;
 732         initStyleOption(&opt);
 733         opt.shape = QRubberBand::Rectangle;
 734         opt.opaque = false;
 735         opt.rect = rubberBandRect.toRect();
 736         style()->drawControl(QStyle::CE_RubberBand, &opt, painter);
 737     }
 738
 739     if (!m_dropIndicator.isEmpty()) {
 740         const QRectF r = m_dropIndicator.toRect();
 741
 742         QColor color = palette().brush(QPalette::Normal, QPalette::Text).color();
 743         painter->setPen(color);
 744
 745         // TODO: The following implementation works only for a vertical scroll-orientation
 746         // and assumes a height of the m_draggingInsertIndicator of 1.
 747         Q_ASSERT(r.height() == 1);
 748         painter->drawLine(r.left() + 1, r.top(), r.right() - 1, r.top());
 749
 750         color.setAlpha(128);
 751         painter->setPen(color);
 752         painter->drawRect(r.left(), r.top() - 1, r.width() - 1, 2);
 753     }
 754 }
 755
 756 QVariant KItemListView::itemChange(GraphicsItemChange change, const QVariant &value)
 757 {
 758     if (change == QGraphicsItem::ItemSceneHasChanged && scene()) {
 759         if (!scene()->views().isEmpty()) {
 760             m_styleOption.palette = scene()->views().at(0)->palette();
 761         }
 762     }
 763     return QGraphicsItem::itemChange(change, value);
 764 }
 765
 766 void KItemListView::setItemSize(const QSizeF& size)
 767 {
 768     const QSizeF previousSize = m_itemSize;
 769     if (size == previousSize) {
 770         return;
 771     }
 772
 773     // Skip animations when the number of rows or columns
 774     // are changed in the grid layout. Although the animation
 775     // engine can handle this usecase, it looks obtrusive.
 776     const bool animate = !changesItemGridLayout(m_layouter->size(),
 777                                                 size,
 778                                                 m_layouter->itemMargin());
 779
 780     const bool alternateBackgroundsChanged = m_alternateBackgrounds &&
 781                                              (( m_itemSize.isEmpty() && !size.isEmpty()) ||
 782                                               (!m_itemSize.isEmpty() && size.isEmpty()));
 783
 784     m_itemSize = size;
 785
 786     if (alternateBackgroundsChanged) {
 787         // For an empty item size alternate backgrounds are drawn if more than
 788         // one role is shown. Assure that the backgrounds for visible items are
 789         // updated when changing the size in this context.
 790         updateAlternateBackgrounds();
 791     }
 792
 793     if (size.isEmpty()) {
 794         if (m_headerWidget->automaticColumnResizing()) {
 795             updatePreferredColumnWidths();
 796         } else {
 797             // Only apply the changed height and respect the header widths
 798             // set by the user
 799             const qreal currentWidth = m_layouter->itemSize().width();
 800             const QSizeF newSize(currentWidth, size.height());
 801             m_layouter->setItemSize(newSize);
 802         }
 803     } else {
 804         m_layouter->setItemSize(size);
 805     }
 806
 807     m_sizeHintResolver->clearCache();
 808     doLayout(animate ? Animation : NoAnimation);
 809     onItemSizeChanged(size, previousSize);
 810 }
 811
 812 void KItemListView::setStyleOption(const KItemListStyleOption& option)
 813 {
 814     if (m_styleOption == option) {
 815         return;
 816     }
 817
 818     const KItemListStyleOption previousOption = m_styleOption;
 819     m_styleOption = option;
 820
 821     bool animate = true;
 822     const QSizeF margin(option.horizontalMargin, option.verticalMargin);
 823     if (margin != m_layouter->itemMargin()) {
 824         // Skip animations when the number of rows or columns
 825         // are changed in the grid layout. Although the animation
 826         // engine can handle this usecase, it looks obtrusive.
 827         animate = !changesItemGridLayout(m_layouter->size(),
 828                                          m_layouter->itemSize(),
 829                                          margin);
 830         m_layouter->setItemMargin(margin);
 831     }
 832
 833     if (m_grouped) {
 834         updateGroupHeaderHeight();
 835     }
 836
 837     if (animate &&
 838         (previousOption.maxTextLines != option.maxTextLines || previousOption.maxTextWidth != option.maxTextWidth)) {
 839         // Animating a change of the maximum text size just results in expensive
 840         // temporary eliding and clipping operations and does not look good visually.
 841         animate = false;
 842     }
 843
 844     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 845     while (it.hasNext()) {
 846         it.next();
 847         it.value()->setStyleOption(option);
 848     }
 849
 850     m_sizeHintResolver->clearCache();
 851     m_layouter->markAsDirty();
 852     doLayout(animate ? Animation : NoAnimation);
 853
 854     if (m_itemSize.isEmpty()) {
 855         updatePreferredColumnWidths();
 856     }
 857
 858     onStyleOptionChanged(option, previousOption);
 859 }
 860
 861 void KItemListView::setScrollOrientation(Qt::Orientation orientation)
 862 {
 863     const Qt::Orientation previousOrientation = m_layouter->scrollOrientation();
 864     if (orientation == previousOrientation) {
 865         return;
 866     }
 867
 868     m_layouter->setScrollOrientation(orientation);
 869     m_animation->setScrollOrientation(orientation);
 870     m_sizeHintResolver->clearCache();
 871
 872     if (m_grouped) {
 873         QMutableHashIterator<KItemListWidget*, KItemListGroupHeader*> it (m_visibleGroups);
 874         while (it.hasNext()) {
 875             it.next();
 876             it.value()->setScrollOrientation(orientation);
 877         }
 878         updateGroupHeaderHeight();
 879
 880     }
 881
 882     doLayout(NoAnimation);
 883
 884     onScrollOrientationChanged(orientation, previousOrientation);
 885     Q_EMIT scrollOrientationChanged(orientation, previousOrientation);
 886 }
 887
 888 Qt::Orientation KItemListView::scrollOrientation() const
 889 {
 890     return m_layouter->scrollOrientation();
 891 }
 892
 893 KItemListWidgetCreatorBase* KItemListView::defaultWidgetCreator() const
 894 {
 895     return nullptr;
 896 }
 897
 898 KItemListGroupHeaderCreatorBase* KItemListView::defaultGroupHeaderCreator() const
 899 {
 900     return nullptr;
 901 }
 902
 903 void KItemListView::initializeItemListWidget(KItemListWidget* item)
 904 {
 905     Q_UNUSED(item)
 906 }
 907
 908 bool KItemListView::itemSizeHintUpdateRequired(const QSet<QByteArray>& changedRoles) const
 909 {
 910     Q_UNUSED(changedRoles)
 911     return true;
 912 }
 913
 914 void KItemListView::onControllerChanged(KItemListController* current, KItemListController* previous)
 915 {
 916     Q_UNUSED(current)
 917     Q_UNUSED(previous)
 918 }
 919
 920 void KItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 921 {
 922     Q_UNUSED(current)
 923     Q_UNUSED(previous)
 924 }
 925
 926 void KItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 927 {
 928     Q_UNUSED(current)
 929     Q_UNUSED(previous)
 930 }
 931
 932 void KItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 933 {
 934     Q_UNUSED(current)
 935     Q_UNUSED(previous)
 936 }
 937
 938 void KItemListView::onScrollOffsetChanged(qreal current, qreal previous)
 939 {
 940     Q_UNUSED(current)
 941     Q_UNUSED(previous)
 942 }
 943
 944 void KItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 945 {
 946     Q_UNUSED(current)
 947     Q_UNUSED(previous)
 948 }
 949
 950 void KItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 951 {
 952     Q_UNUSED(current)
 953     Q_UNUSED(previous)
 954 }
 955
 956 void KItemListView::onHighlightEntireRowChanged(bool highlightEntireRow)
 957 {
 958     Q_UNUSED(highlightEntireRow)
 959 }
 960
 961 void KItemListView::onSupportsItemExpandingChanged(bool supportsExpanding)
 962 {
 963     Q_UNUSED(supportsExpanding)
 964 }
 965
 966 void KItemListView::onTransactionBegin()
 967 {
 968 }
 969
 970 void KItemListView::onTransactionEnd()
 971 {
 972 }
 973
 974 bool KItemListView::event(QEvent* event)
 975 {
 976     switch (event->type()) {
 977     case QEvent::PaletteChange:
 978         updatePalette();
 979         break;
 980
 981     case QEvent::FontChange:
 982         updateFont();
 983         break;
 984
 985     default:
 986         // Forward all other events to the controller and handle them there
 987         if (!m_editingRole && m_controller && m_controller->processEvent(event, transform())) {
 988             event->accept();
 989             return true;
 990         }
 991     }
 992
 993     return QGraphicsWidget::event(event);
 994 }
 995
 996 void KItemListView::mousePressEvent(QGraphicsSceneMouseEvent* event)
 997 {
 998     m_mousePos = transform().map(event->pos());
 999     event->accept();
1000 }
1001
1002 void KItemListView::mouseMoveEvent(QGraphicsSceneMouseEvent* event)
1003 {
1004     QGraphicsWidget::mouseMoveEvent(event);
1005
1006     m_mousePos = transform().map(event->pos());
1007     if (m_autoScrollTimer && !m_autoScrollTimer->isActive()) {
1008         m_autoScrollTimer->start(InitialAutoScrollDelay);
1009     }
1010 }
1011
1012 void KItemListView::dragEnterEvent(QGraphicsSceneDragDropEvent* event)
1013 {
1014     event->setAccepted(true);
1015     setAutoScroll(true);
1016 }
1017
1018 void KItemListView::dragMoveEvent(QGraphicsSceneDragDropEvent* event)
1019 {
1020     QGraphicsWidget::dragMoveEvent(event);
1021
1022     m_mousePos = transform().map(event->pos());
1023     if (m_autoScrollTimer && !m_autoScrollTimer->isActive()) {
1024         m_autoScrollTimer->start(InitialAutoScrollDelay);
1025     }
1026 }
1027
1028 void KItemListView::dragLeaveEvent(QGraphicsSceneDragDropEvent* event)
1029 {
1030     QGraphicsWidget::dragLeaveEvent(event);
1031     setAutoScroll(false);
1032 }
1033
1034 void KItemListView::dropEvent(QGraphicsSceneDragDropEvent* event)
1035 {
1036     QGraphicsWidget::dropEvent(event);
1037     setAutoScroll(false);
1038 }
1039
1040 QList<KItemListWidget*> KItemListView::visibleItemListWidgets() const
1041 {
1042     return m_visibleItems.values();
1043 }
1044
1045 void KItemListView::updateFont()
1046 {
1047     if (scene() && !scene()->views().isEmpty()) {
1048         KItemListStyleOption option = styleOption();
1049         option.font = scene()->views().first()->font();
1050         option.fontMetrics = QFontMetrics(option.font);
1051
1052         setStyleOption(option);
1053     }
1054 }
1055
1056 void KItemListView::updatePalette()
1057 {
1058     if (scene() && !scene()->views().isEmpty()) {
1059         KItemListStyleOption option = styleOption();
1060         option.palette = scene()->views().first()->palette();
1061
1062         setStyleOption(option);
1063     }
1064 }
1065
1066 void KItemListView::slotItemsInserted(const KItemRangeList& itemRanges)
1067 {
1068     if (m_itemSize.isEmpty()) {
1069         updatePreferredColumnWidths(itemRanges);
1070     }
1071
1072     const bool hasMultipleRanges = (itemRanges.count() > 1);
1073     if (hasMultipleRanges) {
1074         beginTransaction();
1075     }
1076
1077     m_layouter->markAsDirty();
1078
1079     m_sizeHintResolver->itemsInserted(itemRanges);
1080
1081     int previouslyInsertedCount = 0;
1082     for (const KItemRange& range : itemRanges) {
1083         // range.index is related to the model before anything has been inserted.
1084         // As in each loop the current item-range gets inserted the index must
1085         // be increased by the already previously inserted items.
1086         const int index = range.index + previouslyInsertedCount;
1087         const int count = range.count;
1088         if (index < 0 || count <= 0) {
1089             qCWarning(DolphinDebug) << "Invalid item range (index:" << index << ", count:" << count << ")";
1090             continue;
1091         }
1092         previouslyInsertedCount += count;
1093
1094         // Determine which visible items must be moved
1095         QList<int> itemsToMove;
1096         QHashIterator<int, KItemListWidget*> it(m_visibleItems);
1097         while (it.hasNext()) {
1098             it.next();
1099             const int visibleItemIndex = it.key();
1100             if (visibleItemIndex >= index) {
1101                 itemsToMove.append(visibleItemIndex);
1102             }
1103         }
1104
1105         // Update the indexes of all KItemListWidget instances that are located
1106         // after the inserted items. It is important to adjust the indexes in the order
1107         // from the highest index to the lowest index to prevent overlaps when setting the new index.
1108         std::sort(itemsToMove.begin(), itemsToMove.end());
1109         for (int i = itemsToMove.count() - 1; i >= 0; --i) {
1110             KItemListWidget* widget = m_visibleItems.value(itemsToMove[i]);
1111             Q_ASSERT(widget);
1112             const int newIndex = widget->index() + count;
1113             if (hasMultipleRanges) {
1114                 setWidgetIndex(widget, newIndex);
1115             } else {
1116                 // Try to animate the moving of the item
1117                 moveWidgetToIndex(widget, newIndex);
1118             }
1119         }
1120
1121         if (m_model->count() == count && m_activeTransactions == 0) {
1122             // Check whether a scrollbar is required to show the inserted items. In this case
1123             // the size of the layouter will be decreased before calling doLayout(): This prevents
1124             // an unnecessary temporary animation due to the geometry change of the inserted scrollbar.
1125             const bool verticalScrollOrientation = (scrollOrientation() == Qt::Vertical);
1126             const bool decreaseLayouterSize = ( verticalScrollOrientation && maximumScrollOffset() > size().height()) ||
1127                                               (!verticalScrollOrientation && maximumScrollOffset() > size().width());
1128             if (decreaseLayouterSize) {
1129                 const int scrollBarExtent = style()->pixelMetric(QStyle::PM_ScrollBarExtent);
1130
1131                 int scrollbarSpacing = 0;
1132                 if (style()->styleHint(QStyle::SH_ScrollView_FrameOnlyAroundContents)) {
1133                     scrollbarSpacing = style()->pixelMetric(QStyle::PM_ScrollView_ScrollBarSpacing);
1134                 }
1135
1136                 QSizeF layouterSize = m_layouter->size();
1137                 if (verticalScrollOrientation) {
1138                     layouterSize.rwidth() -= scrollBarExtent + scrollbarSpacing;
1139                 } else {
1140                     layouterSize.rheight() -= scrollBarExtent + scrollbarSpacing;
1141                 }
1142                 m_layouter->setSize(layouterSize);
1143             }
1144         }
1145
1146         if (!hasMultipleRanges) {
1147             doLayout(animateChangedItemCount(count) ? Animation : NoAnimation, index, count);
1148             updateSiblingsInformation();
1149         }
1150     }
1151
1152     if (m_controller) {
1153         m_controller->selectionManager()->itemsInserted(itemRanges);
1154     }
1155
1156     if (hasMultipleRanges) {
1157         m_endTransactionAnimationHint = NoAnimation;
1158         endTransaction();
1159
1160         updateSiblingsInformation();
1161     }
1162
1163     if (m_grouped && (hasMultipleRanges || itemRanges.first().count < m_model->count())) {
1164         // In case if items of the same group have been inserted before an item that
1165         // currently represents the first item of the group, the group header of
1166         // this item must be removed.
1167         updateVisibleGroupHeaders();
1168     }
1169
1170     if (useAlternateBackgrounds()) {
1171         updateAlternateBackgrounds();
1172     }
1173 }
1174
1175 void KItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
1176 {
1177     if (m_itemSize.isEmpty()) {
1178         // Don't pass the item-range: The preferred column-widths of
1179         // all items must be adjusted when removing items.
1180         updatePreferredColumnWidths();
1181     }
1182
1183     const bool hasMultipleRanges = (itemRanges.count() > 1);
1184     if (hasMultipleRanges) {
1185         beginTransaction();
1186     }
1187
1188     m_layouter->markAsDirty();
1189
1190     m_sizeHintResolver->itemsRemoved(itemRanges);
1191
1192     for (int i = itemRanges.count() - 1; i >= 0; --i) {
1193         const KItemRange& range = itemRanges[i];
1194         const int index = range.index;
1195         const int count = range.count;
1196         if (index < 0 || count <= 0) {
1197             qCWarning(DolphinDebug) << "Invalid item range (index:" << index << ", count:" << count << ")";
1198             continue;
1199         }
1200
1201         const int firstRemovedIndex = index;
1202         const int lastRemovedIndex = index + count - 1;
1203
1204         // Remember which items have to be moved because they are behind the removed range.
1205         QVector<int> itemsToMove;
1206
1207         // Remove all KItemListWidget instances that got deleted
1208         // Iterate over a const copy because the container is mutated within the loop
1209         // directly and in `recycleWidget()` (https://bugs.kde.org/show_bug.cgi?id=428374)
1210         const auto visibleItems = m_visibleItems;
1211         for (KItemListWidget* widget : visibleItems) {
1212             const int i = widget->index();
1213             if (i < firstRemovedIndex) {
1214                 continue;
1215             } else if (i > lastRemovedIndex) {
1216                 itemsToMove.append(i);
1217                 continue;
1218             }
1219
1220             m_animation->stop(widget);
1221             // Stopping the animation might lead to recycling the widget if
1222             // it is invisible (see slotAnimationFinished()).
1223             // Check again whether it is still visible:
1224             if (!m_visibleItems.contains(i)) {
1225                 continue;
1226             }
1227
1228             if (m_model->count() == 0 || hasMultipleRanges || !animateChangedItemCount(count)) {
1229                 // Remove the widget without animation
1230                 recycleWidget(widget);
1231             } else {
1232                 // Animate the removing of the items. Special case: When removing an item there
1233                 // is no valid model index available anymore. For the
1234                 // remove-animation the item gets removed from m_visibleItems but the widget
1235                 // will stay alive until the animation has been finished and will
1236                 // be recycled (deleted) in KItemListView::slotAnimationFinished().
1237                 m_visibleItems.remove(i);
1238                 widget->setIndex(-1);
1239                 m_animation->start(widget, KItemListViewAnimation::DeleteAnimation);
1240             }
1241         }
1242
1243         // Update the indexes of all KItemListWidget instances that are located
1244         // after the deleted items. It is important to update them in ascending
1245         // order to prevent overlaps when setting the new index.
1246         std::sort(itemsToMove.begin(), itemsToMove.end());
1247         for (int i : qAsConst(itemsToMove)) {
1248             KItemListWidget* widget = m_visibleItems.value(i);
1249             Q_ASSERT(widget);
1250             const int newIndex = i - count;
1251             if (hasMultipleRanges) {
1252                 setWidgetIndex(widget, newIndex);
1253             } else {
1254                 // Try to animate the moving of the item
1255                 moveWidgetToIndex(widget, newIndex);
1256             }
1257         }
1258
1259         if (!hasMultipleRanges) {
1260             // The decrease-layout-size optimization in KItemListView::slotItemsInserted()
1261             // assumes an updated geometry. If items are removed during an active transaction,
1262             // the transaction will be temporary deactivated so that doLayout() triggers a
1263             // geometry update if necessary.
1264             const int activeTransactions = m_activeTransactions;
1265             m_activeTransactions = 0;
1266             doLayout(animateChangedItemCount(count) ? Animation : NoAnimation, index, -count);
1267             m_activeTransactions = activeTransactions;
1268             updateSiblingsInformation();
1269         }
1270     }
1271
1272     if (m_controller) {
1273         m_controller->selectionManager()->itemsRemoved(itemRanges);
1274     }
1275
1276     if (hasMultipleRanges) {
1277         m_endTransactionAnimationHint = NoAnimation;
1278         endTransaction();
1279         updateSiblingsInformation();
1280     }
1281
1282     if (m_grouped && (hasMultipleRanges || m_model->count() > 0)) {
1283         // In case if the first item of a group has been removed, the group header
1284         // must be applied to the next visible item.
1285         updateVisibleGroupHeaders();
1286     }
1287
1288     if (useAlternateBackgrounds()) {
1289         updateAlternateBackgrounds();
1290     }
1291 }
1292
1293 void KItemListView::slotItemsMoved(const KItemRange& itemRange, const QList<int>& movedToIndexes)
1294 {
1295     m_sizeHintResolver->itemsMoved(itemRange, movedToIndexes);
1296     m_layouter->markAsDirty();
1297
1298     if (m_controller) {
1299         m_controller->selectionManager()->itemsMoved(itemRange, movedToIndexes);
1300     }
1301
1302     const int firstVisibleMovedIndex = qMax(firstVisibleIndex(), itemRange.index);
1303     const int lastVisibleMovedIndex = qMin(lastVisibleIndex(), itemRange.index + itemRange.count - 1);
1304
1305     for (int index = firstVisibleMovedIndex; index <= lastVisibleMovedIndex; ++index) {
1306         KItemListWidget* widget = m_visibleItems.value(index);
1307         if (widget) {
1308             updateWidgetProperties(widget, index);
1309             initializeItemListWidget(widget);
1310         }
1311     }
1312
1313     doLayout(NoAnimation);
1314     updateSiblingsInformation();
1315 }
1316
1317 void KItemListView::slotItemsChanged(const KItemRangeList& itemRanges,
1318                                      const QSet<QByteArray>& roles)
1319 {
1320     const bool updateSizeHints = itemSizeHintUpdateRequired(roles);
1321     if (updateSizeHints && m_itemSize.isEmpty()) {
1322         updatePreferredColumnWidths(itemRanges);
1323     }
1324
1325     for (const KItemRange& itemRange : itemRanges) {
1326         const int index = itemRange.index;
1327         const int count = itemRange.count;
1328
1329         if (updateSizeHints) {
1330             m_sizeHintResolver->itemsChanged(index, count, roles);
1331             m_layouter->markAsDirty();
1332         }
1333
1334         // Apply the changed roles to the visible item-widgets
1335         const int lastIndex = index + count - 1;
1336         for (int i = index; i <= lastIndex; ++i) {
1337             KItemListWidget* widget = m_visibleItems.value(i);
1338             if (widget) {
1339                 widget->setData(m_model->data(i), roles);
1340             }
1341         }
1342
1343         if (m_grouped && roles.contains(m_model->sortRole())) {
1344             // The sort-role has been changed which might result
1345             // in modified group headers
1346             updateVisibleGroupHeaders();
1347             doLayout(NoAnimation);
1348         }
1349
1350         QAccessibleTableModelChangeEvent ev(this, QAccessibleTableModelChangeEvent::DataChanged);
1351         ev.setFirstRow(itemRange.index);
1352         ev.setLastRow(itemRange.index + itemRange.count);
1353         QAccessible::updateAccessibility(&ev);
1354     }
1355
1356     doLayout(NoAnimation);
1357 }
1358
1359 void KItemListView::slotGroupsChanged()
1360 {
1361     updateVisibleGroupHeaders();
1362     doLayout(NoAnimation);
1363     updateSiblingsInformation();
1364 }
1365
1366 void KItemListView::slotGroupedSortingChanged(bool current)
1367 {
1368     m_grouped = current;
1369     m_layouter->markAsDirty();
1370
1371     if (m_grouped) {
1372         updateGroupHeaderHeight();
1373     } else {
1374         // Clear all visible headers. Note that the QHashIterator takes a copy of
1375         // m_visibleGroups. Therefore, it remains valid even if items are removed
1376         // from m_visibleGroups in recycleGroupHeaderForWidget().
1377         QHashIterator<KItemListWidget*, KItemListGroupHeader*> it(m_visibleGroups);
1378         while (it.hasNext()) {
1379             it.next();
1380             recycleGroupHeaderForWidget(it.key());
1381         }
1382         Q_ASSERT(m_visibleGroups.isEmpty());
1383     }
1384
1385     if (useAlternateBackgrounds()) {
1386         // Changing the group mode requires to update the alternate backgrounds
1387         // as with the enabled group mode the altering is done on base of the first
1388         // group item.
1389         updateAlternateBackgrounds();
1390     }
1391     updateSiblingsInformation();
1392     doLayout(NoAnimation);
1393 }
1394
1395 void KItemListView::slotSortOrderChanged(Qt::SortOrder current, Qt::SortOrder previous)
1396 {
1397     Q_UNUSED(current)
1398     Q_UNUSED(previous)
1399     if (m_grouped) {
1400         updateVisibleGroupHeaders();
1401         doLayout(NoAnimation);
1402     }
1403 }
1404
1405 void KItemListView::slotSortRoleChanged(const QByteArray& current, const QByteArray& previous)
1406 {
1407     Q_UNUSED(current)
1408     Q_UNUSED(previous)
1409     if (m_grouped) {
1410         updateVisibleGroupHeaders();
1411         doLayout(NoAnimation);
1412     }
1413 }
1414
1415 void KItemListView::slotCurrentChanged(int current, int previous)
1416 {
1417     Q_UNUSED(previous)
1418
1419     // In SingleSelection mode (e.g., in the Places Panel), the current item is
1420     // always the selected item. It is not necessary to highlight the current item then.
1421     if (m_controller->selectionBehavior() != KItemListController::SingleSelection) {
1422         KItemListWidget* previousWidget = m_visibleItems.value(previous, nullptr);
1423         if (previousWidget) {
1424             previousWidget->setCurrent(false);
1425         }
1426
1427         KItemListWidget* currentWidget = m_visibleItems.value(current, nullptr);
1428         if (currentWidget) {
1429             currentWidget->setCurrent(true);
1430         }
1431     }
1432
1433     QAccessibleEvent ev(this, QAccessible::Focus);
1434     ev.setChild(current);
1435     QAccessible::updateAccessibility(&ev);
1436 }
1437
1438 void KItemListView::slotSelectionChanged(const KItemSet& current, const KItemSet& previous)
1439 {
1440     Q_UNUSED(previous)
1441
1442     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
1443     while (it.hasNext()) {
1444         it.next();
1445         const int index = it.key();
1446         KItemListWidget* widget = it.value();
1447         widget->setSelected(current.contains(index));
1448     }
1449 }
1450
1451 void KItemListView::slotAnimationFinished(QGraphicsWidget* widget,
1452                                           KItemListViewAnimation::AnimationType type)
1453 {
1454     KItemListWidget* itemListWidget = qobject_cast<KItemListWidget*>(widget);
1455     Q_ASSERT(itemListWidget);
1456
1457     if (type == KItemListViewAnimation::DeleteAnimation) {
1458         // As we recycle the widget in this case it is important to assure that no
1459         // other animation has been started. This is a convention in KItemListView and
1460         // not a requirement defined by KItemListViewAnimation.
1461         Q_ASSERT(!m_animation->isStarted(itemListWidget));
1462
1463         // All KItemListWidgets that are animated by the DeleteAnimation are not maintained
1464         // by m_visibleWidgets and must be deleted manually after the animation has
1465         // been finished.
1466         recycleGroupHeaderForWidget(itemListWidget);
1467         widgetCreator()->recycle(itemListWidget);
1468     } else {
1469         const int index = itemListWidget->index();
1470         const bool invisible = (index < m_layouter->firstVisibleIndex()) ||
1471                                (index > m_layouter->lastVisibleIndex());
1472         if (invisible && !m_animation->isStarted(itemListWidget)) {
1473             recycleWidget(itemListWidget);
1474         }
1475     }
1476 }
1477
1478 void KItemListView::slotRubberBandPosChanged()
1479 {
1480     update();
1481 }
1482
1483 void KItemListView::slotRubberBandActivationChanged(bool active)
1484 {
1485     if (active) {
1486         connect(m_rubberBand, &KItemListRubberBand::startPositionChanged, this, &KItemListView::slotRubberBandPosChanged);
1487         connect(m_rubberBand, &KItemListRubberBand::endPositionChanged, this, &KItemListView::slotRubberBandPosChanged);
1488         m_skipAutoScrollForRubberBand = true;
1489     } else {
1490         QRectF rubberBandRect = QRectF(m_rubberBand->startPosition(),
1491                                        m_rubberBand->endPosition()).normalized();
1492
1493         auto animation = new QVariantAnimation(this);
1494         animation->setStartValue(1.0);
1495         animation->setEndValue(0.0);
1496         animation->setDuration(RubberFadeSpeed);
1497         animation->setProperty(RubberPropertyName, rubberBandRect);
1498
1499         QEasingCurve curve;
1500         curve.setType(QEasingCurve::BezierSpline);
1501         curve.addCubicBezierSegment(QPointF(0.4, 0.0), QPointF(1.0, 1.0), QPointF(1.0, 1.0));
1502         animation->setEasingCurve(curve);
1503
1504         connect(animation, &QVariantAnimation::valueChanged, this, [=](const QVariant&) {
1505             update();
1506         });
1507         connect(animation, &QVariantAnimation::finished, this, [=]() {
1508             m_rubberBandAnimations.removeAll(animation);
1509             delete animation;
1510         });
1511         animation->start();
1512         m_rubberBandAnimations << animation;
1513
1514         disconnect(m_rubberBand, &KItemListRubberBand::startPositionChanged, this, &KItemListView::slotRubberBandPosChanged);
1515         disconnect(m_rubberBand, &KItemListRubberBand::endPositionChanged, this, &KItemListView::slotRubberBandPosChanged);
1516         m_skipAutoScrollForRubberBand = false;
1517     }
1518
1519     update();
1520 }
1521
1522 void KItemListView::slotHeaderColumnWidthChanged(const QByteArray& role,
1523                                                  qreal currentWidth,
1524                                                  qreal previousWidth)
1525 {
1526     Q_UNUSED(role)
1527     Q_UNUSED(currentWidth)
1528     Q_UNUSED(previousWidth)
1529
1530     m_headerWidget->setAutomaticColumnResizing(false);
1531     applyColumnWidthsFromHeader();
1532     doLayout(NoAnimation);
1533 }
1534
1535 void KItemListView::slotLeadingPaddingChanged(qreal width)
1536 {
1537     Q_UNUSED(width)
1538     if (m_headerWidget->automaticColumnResizing()) {
1539         applyAutomaticColumnWidths();
1540     }
1541     applyColumnWidthsFromHeader();
1542     doLayout(NoAnimation);
1543 }
1544
1545 void KItemListView::slotHeaderColumnMoved(const QByteArray& role,
1546                                           int currentIndex,
1547                                           int previousIndex)
1548 {
1549     Q_ASSERT(m_visibleRoles[previousIndex] == role);
1550
1551     const QList<QByteArray> previous = m_visibleRoles;
1552
1553     QList<QByteArray> current = m_visibleRoles;
1554     current.removeAt(previousIndex);
1555     current.insert(currentIndex, role);
1556
1557     setVisibleRoles(current);
1558
1559     Q_EMIT visibleRolesChanged(current, previous);
1560 }
1561
1562 void KItemListView::triggerAutoScrolling()
1563 {
1564     if (!m_autoScrollTimer) {
1565         return;
1566     }
1567
1568     int pos = 0;
1569     int visibleSize = 0;
1570     if (scrollOrientation() == Qt::Vertical) {
1571         pos = m_mousePos.y();
1572         visibleSize = size().height();
1573     } else {
1574         pos = m_mousePos.x();
1575         visibleSize = size().width();
1576     }
1577
1578     if (m_autoScrollTimer->interval() == InitialAutoScrollDelay) {
1579         m_autoScrollIncrement = 0;
1580     }
1581
1582     m_autoScrollIncrement = calculateAutoScrollingIncrement(pos, visibleSize, m_autoScrollIncrement);
1583     if (m_autoScrollIncrement == 0) {
1584         // The mouse position is not above an autoscroll margin (the autoscroll timer
1585         // will be restarted in mouseMoveEvent())
1586         m_autoScrollTimer->stop();
1587         return;
1588     }
1589
1590     if (m_rubberBand->isActive() && m_skipAutoScrollForRubberBand) {
1591         // If a rubberband selection is ongoing the autoscrolling may only get triggered
1592         // if the direction of the rubberband is similar to the autoscroll direction. This
1593         // prevents that starting to create a rubberband within the autoscroll margins starts
1594         // an autoscrolling.
1595
1596         const qreal minDiff = 4; // Ignore any autoscrolling if the rubberband is very small
1597         const qreal diff = (scrollOrientation() == Qt::Vertical)
1598                            ? m_rubberBand->endPosition().y() - m_rubberBand->startPosition().y()
1599                            : m_rubberBand->endPosition().x() - m_rubberBand->startPosition().x();
1600         if (qAbs(diff) < minDiff || (m_autoScrollIncrement < 0 && diff > 0) || (m_autoScrollIncrement > 0 && diff < 0)) {
1601             // The rubberband direction is different from the scroll direction (e.g. the rubberband has
1602             // been moved up although the autoscroll direction might be down)
1603             m_autoScrollTimer->stop();
1604             return;
1605         }
1606     }
1607
1608     // As soon as the autoscrolling has been triggered at least once despite having an active rubberband,
1609     // the autoscrolling may not get skipped anymore until a new rubberband is created
1610     m_skipAutoScrollForRubberBand = false;
1611
1612     const qreal maxVisibleOffset = qMax(qreal(0), maximumScrollOffset() - visibleSize);
1613     const qreal newScrollOffset = qMin(scrollOffset() + m_autoScrollIncrement, maxVisibleOffset);
1614     setScrollOffset(newScrollOffset);
1615
1616     // Trigger the autoscroll timer which will periodically call
1617     // triggerAutoScrolling()
1618     m_autoScrollTimer->start(RepeatingAutoScrollDelay);
1619 }
1620
1621 void KItemListView::slotGeometryOfGroupHeaderParentChanged()
1622 {
1623     KItemListWidget* widget = qobject_cast<KItemListWidget*>(sender());
1624     Q_ASSERT(widget);
1625     KItemListGroupHeader* groupHeader = m_visibleGroups.value(widget);
1626     Q_ASSERT(groupHeader);
1627     updateGroupHeaderLayout(widget);
1628 }
1629
1630 void KItemListView::slotRoleEditingCanceled(int index, const QByteArray& role, const QVariant& value)
1631 {
1632     disconnectRoleEditingSignals(index);
1633
1634     m_editingRole = false;
1635     Q_EMIT roleEditingCanceled(index, role, value);
1636 }
1637
1638 void KItemListView::slotRoleEditingFinished(int index, const QByteArray& role, const QVariant& value)
1639 {
1640     disconnectRoleEditingSignals(index);
1641
1642     m_editingRole = false;
1643     Q_EMIT roleEditingFinished(index, role, value);
1644 }
1645
1646 void KItemListView::setController(KItemListController* controller)
1647 {
1648     if (m_controller != controller) {
1649         KItemListController* previous = m_controller;
1650         if (previous) {
1651             KItemListSelectionManager* selectionManager = previous->selectionManager();
1652             disconnect(selectionManager, &KItemListSelectionManager::currentChanged, this, &KItemListView::slotCurrentChanged);
1653             disconnect(selectionManager, &KItemListSelectionManager::selectionChanged, this, &KItemListView::slotSelectionChanged);
1654         }
1655
1656         m_controller = controller;
1657
1658         if (controller) {
1659             KItemListSelectionManager* selectionManager = controller->selectionManager();
1660             connect(selectionManager, &KItemListSelectionManager::currentChanged, this, &KItemListView::slotCurrentChanged);
1661             connect(selectionManager, &KItemListSelectionManager::selectionChanged, this, &KItemListView::slotSelectionChanged);
1662         }
1663
1664         onControllerChanged(controller, previous);
1665     }
1666 }
1667
1668 void KItemListView::setModel(KItemModelBase* model)
1669 {
1670     if (m_model == model) {
1671         return;
1672     }
1673
1674     KItemModelBase* previous = m_model;
1675
1676     if (m_model) {
1677         disconnect(m_model, &KItemModelBase::itemsChanged,
1678                    this,    &KItemListView::slotItemsChanged);
1679         disconnect(m_model, &KItemModelBase::itemsInserted,
1680                    this,    &KItemListView::slotItemsInserted);
1681         disconnect(m_model, &KItemModelBase::itemsRemoved,
1682                    this,    &KItemListView::slotItemsRemoved);
1683         disconnect(m_model, &KItemModelBase::itemsMoved,
1684                    this,    &KItemListView::slotItemsMoved);
1685         disconnect(m_model, &KItemModelBase::groupsChanged,
1686                    this,    &KItemListView::slotGroupsChanged);
1687         disconnect(m_model, &KItemModelBase::groupedSortingChanged,
1688                    this,    &KItemListView::slotGroupedSortingChanged);
1689         disconnect(m_model, &KItemModelBase::sortOrderChanged,
1690                    this,    &KItemListView::slotSortOrderChanged);
1691         disconnect(m_model, &KItemModelBase::sortRoleChanged,
1692                    this,    &KItemListView::slotSortRoleChanged);
1693
1694         m_sizeHintResolver->itemsRemoved(KItemRangeList() << KItemRange(0, m_model->count()));
1695     }
1696
1697     m_model = model;
1698     m_layouter->setModel(model);
1699     m_grouped = model->groupedSorting();
1700
1701     if (m_model) {
1702         connect(m_model, &KItemModelBase::itemsChanged,
1703                 this,    &KItemListView::slotItemsChanged);
1704         connect(m_model, &KItemModelBase::itemsInserted,
1705                 this,    &KItemListView::slotItemsInserted);
1706         connect(m_model, &KItemModelBase::itemsRemoved,
1707                 this,    &KItemListView::slotItemsRemoved);
1708         connect(m_model, &KItemModelBase::itemsMoved,
1709                 this,    &KItemListView::slotItemsMoved);
1710         connect(m_model, &KItemModelBase::groupsChanged,
1711                 this,    &KItemListView::slotGroupsChanged);
1712         connect(m_model, &KItemModelBase::groupedSortingChanged,
1713                 this,    &KItemListView::slotGroupedSortingChanged);
1714         connect(m_model, &KItemModelBase::sortOrderChanged,
1715                 this,    &KItemListView::slotSortOrderChanged);
1716         connect(m_model, &KItemModelBase::sortRoleChanged,
1717                 this,    &KItemListView::slotSortRoleChanged);
1718
1719         const int itemCount = m_model->count();
1720         if (itemCount > 0) {
1721             slotItemsInserted(KItemRangeList() << KItemRange(0, itemCount));
1722         }
1723     }
1724
1725     onModelChanged(model, previous);
1726 }
1727
1728 KItemListRubberBand* KItemListView::rubberBand() const
1729 {
1730     return m_rubberBand;
1731 }
1732
1733 void KItemListView::doLayout(LayoutAnimationHint hint, int changedIndex, int changedCount)
1734 {
1735     if (m_activeTransactions > 0) {
1736         if (hint == NoAnimation) {
1737             // As soon as at least one property change should be done without animation,
1738             // the whole transaction will be marked as not animated.
1739             m_endTransactionAnimationHint = NoAnimation;
1740         }
1741         return;
1742     }
1743
1744     if (!m_model || m_model->count() < 0) {
1745         return;
1746     }
1747
1748     int firstVisibleIndex = m_layouter->firstVisibleIndex();
1749     if (firstVisibleIndex < 0) {
1750         emitOffsetChanges();
1751         return;
1752     }
1753
1754     // Do a sanity check of the scroll-offset property: When properties of the itemlist-view have been changed
1755     // it might be possible that the maximum offset got changed too. Assure that the full visible range
1756     // is still shown if the maximum offset got decreased.
1757     const qreal visibleOffsetRange = (scrollOrientation() == Qt::Horizontal) ? size().width() : size().height();
1758     const qreal maxOffsetToShowFullRange = maximumScrollOffset() - visibleOffsetRange;
1759     if (scrollOffset() > maxOffsetToShowFullRange) {
1760         m_layouter->setScrollOffset(qMax(qreal(0), maxOffsetToShowFullRange));
1761         firstVisibleIndex = m_layouter->firstVisibleIndex();
1762     }
1763
1764     const int lastVisibleIndex = m_layouter->lastVisibleIndex();
1765
1766     int firstSibblingIndex = -1;
1767     int lastSibblingIndex = -1;
1768     const bool supportsExpanding = supportsItemExpanding();
1769
1770     QList<int> reusableItems = recycleInvisibleItems(firstVisibleIndex, lastVisibleIndex, hint);
1771
1772     // Assure that for each visible item a KItemListWidget is available. KItemListWidget
1773     // instances from invisible items are reused. If no reusable items are
1774     // found then new KItemListWidget instances get created.
1775     const bool animate = (hint == Animation);
1776     for (int i = firstVisibleIndex; i <= lastVisibleIndex; ++i) {
1777         bool applyNewPos = true;
1778
1779         const QRectF itemBounds = m_layouter->itemRect(i);
1780         const QPointF newPos = itemBounds.topLeft();
1781         KItemListWidget* widget = m_visibleItems.value(i);
1782         if (!widget) {
1783             if (!reusableItems.isEmpty()) {
1784                 // Reuse a KItemListWidget instance from an invisible item
1785                 const int oldIndex = reusableItems.takeLast();
1786                 widget = m_visibleItems.value(oldIndex);
1787                 setWidgetIndex(widget, i);
1788                 updateWidgetProperties(widget, i);
1789                 initializeItemListWidget(widget);
1790             } else {
1791                 // No reusable KItemListWidget instance is available, create a new one
1792                 widget = createWidget(i);
1793             }
1794             widget->resize(itemBounds.size());
1795
1796             if (animate && changedCount < 0) {
1797                 // Items have been deleted.
1798                 if (i >= changedIndex) {
1799                     // The item is located behind the removed range. Move the
1800                     // created item to the imaginary old position outside the
1801                     // view. It will get animated to the new position later.
1802                     const int previousIndex = i - changedCount;
1803                     const QRectF itemRect = m_layouter->itemRect(previousIndex);
1804                     if (itemRect.isEmpty()) {
1805                         const QPointF invisibleOldPos = (scrollOrientation() == Qt::Vertical)
1806                                                         ? QPointF(0, size().height()) : QPointF(size().width(), 0);
1807                         widget->setPos(invisibleOldPos);
1808                     } else {
1809                         widget->setPos(itemRect.topLeft());
1810                     }
1811                     applyNewPos = false;
1812                 }
1813             }
1814
1815             if (supportsExpanding && changedCount == 0) {
1816                 if (firstSibblingIndex < 0) {
1817                     firstSibblingIndex = i;
1818                 }
1819                 lastSibblingIndex = i;
1820             }
1821         }
1822
1823         if (animate) {
1824             if (m_animation->isStarted(widget, KItemListViewAnimation::MovingAnimation)) {
1825                 m_animation->start(widget,  KItemListViewAnimation::MovingAnimation, newPos);
1826                 applyNewPos = false;
1827             }
1828
1829             const bool itemsRemoved = (changedCount < 0);
1830             const bool itemsInserted = (changedCount > 0);
1831             if (itemsRemoved && (i >= changedIndex)) {
1832                 // The item is located after the removed items. Animate the moving of the position.
1833                 applyNewPos = !moveWidget(widget, newPos);
1834             } else if (itemsInserted && i >= changedIndex) {
1835                 // The item is located after the first inserted item
1836                 if (i <= changedIndex + changedCount - 1) {
1837                     // The item is an inserted item. Animate the appearing of the item.
1838                     // For performance reasons no animation is done when changedCount is equal
1839                     // to all available items.
1840                     if (changedCount < m_model->count()) {
1841                         m_animation->start(widget, KItemListViewAnimation::CreateAnimation);
1842                     }
1843                 } else if (!m_animation->isStarted(widget, KItemListViewAnimation::CreateAnimation)) {
1844                     // The item was already there before, so animate the moving of the position.
1845                     // No moving animation is done if the item is animated by a create animation: This
1846                     // prevents a "move animation mess" when inserting several ranges in parallel.
1847                     applyNewPos = !moveWidget(widget, newPos);
1848                 }
1849             }
1850         } else {
1851             m_animation->stop(widget);
1852         }
1853
1854         if (applyNewPos) {
1855             widget->setPos(newPos);
1856         }
1857
1858         Q_ASSERT(widget->index() == i);
1859         widget->setVisible(true);
1860
1861         if (widget->size() != itemBounds.size()) {
1862             // Resize the widget for the item to the changed size.
1863             if (animate) {
1864                 // If a dynamic item size is used then no animation is done in the direction
1865                 // of the dynamic size.
1866                 if (m_itemSize.width() <= 0) {
1867                     // The width is dynamic, apply the new width without animation.
1868                     widget->resize(itemBounds.width(), widget->size().height());
1869                 } else if (m_itemSize.height() <= 0) {
1870                     // The height is dynamic, apply the new height without animation.
1871                     widget->resize(widget->size().width(), itemBounds.height());
1872                 }
1873                 m_animation->start(widget, KItemListViewAnimation::ResizeAnimation, itemBounds.size());
1874             } else {
1875                 widget->resize(itemBounds.size());
1876             }
1877         }
1878
1879         const int newIconSize = widget->styleOption().iconSize;
1880         if (widget->iconSize() != newIconSize) {
1881             if (animate) {
1882                 m_animation->start(widget, KItemListViewAnimation::IconResizeAnimation, newIconSize);
1883             } else {
1884                 widget->setIconSize(newIconSize);
1885             }
1886         }
1887
1888         // Updating the cell-information must be done as last step: The decision whether the
1889         // moving-animation should be started at all is based on the previous cell-information.
1890         const Cell cell(m_layouter->itemColumn(i), m_layouter->itemRow(i));
1891         m_visibleCells.insert(i, cell);
1892     }
1893
1894     // Delete invisible KItemListWidget instances that have not been reused
1895     for (int index : qAsConst(reusableItems)) {
1896         recycleWidget(m_visibleItems.value(index));
1897     }
1898
1899     if (supportsExpanding && firstSibblingIndex >= 0) {
1900         Q_ASSERT(lastSibblingIndex >= 0);
1901         updateSiblingsInformation(firstSibblingIndex, lastSibblingIndex);
1902     }
1903
1904     if (m_grouped) {
1905         // Update the layout of all visible group headers
1906         QHashIterator<KItemListWidget*, KItemListGroupHeader*> it(m_visibleGroups);
1907         while (it.hasNext()) {
1908             it.next();
1909             updateGroupHeaderLayout(it.key());
1910         }
1911     }
1912
1913     emitOffsetChanges();
1914 }
1915
1916 QList<int> KItemListView::recycleInvisibleItems(int firstVisibleIndex,
1917                                                 int lastVisibleIndex,
1918                                                 LayoutAnimationHint hint)
1919 {
1920     // Determine all items that are completely invisible and might be
1921     // reused for items that just got (at least partly) visible. If the
1922     // animation hint is set to 'Animation' items that do e.g. an animated
1923     // moving of their position are not marked as invisible: This assures
1924     // that a scrolling inside the view can be done without breaking an animation.
1925
1926     QList<int> items;
1927
1928     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
1929     while (it.hasNext()) {
1930         it.next();
1931
1932         KItemListWidget* widget = it.value();
1933         const int index = widget->index();
1934         const bool invisible = (index < firstVisibleIndex) || (index > lastVisibleIndex);
1935
1936         if (invisible) {
1937             if (m_animation->isStarted(widget)) {
1938                 if (hint == NoAnimation) {
1939                     // Stopping the animation will call KItemListView::slotAnimationFinished()
1940                     // and the widget will be recycled if necessary there.
1941                     m_animation->stop(widget);
1942                 }
1943             } else {
1944                 widget->setVisible(false);
1945                 items.append(index);
1946
1947                 if (m_grouped) {
1948                     recycleGroupHeaderForWidget(widget);
1949                 }
1950             }
1951         }
1952     }
1953
1954     return items;
1955 }
1956
1957 bool KItemListView::moveWidget(KItemListWidget* widget,const QPointF& newPos)
1958 {
1959     if (widget->pos() == newPos) {
1960         return false;
1961     }
1962
1963     bool startMovingAnim = false;
1964
1965     if (m_itemSize.isEmpty()) {
1966         // The items are not aligned in a grid but either as columns or rows.
1967         startMovingAnim = true;
1968     } else {
1969         // When having a grid the moving-animation should only be started, if it is done within
1970         // one row in the vertical scroll-orientation or one column in the horizontal scroll-orientation.
1971         // Otherwise instead of a moving-animation a create-animation on the new position will be used
1972         // instead. This is done to prevent overlapping (and confusing) moving-animations.
1973         const int index = widget->index();
1974         const Cell cell = m_visibleCells.value(index);
1975         if (cell.column >= 0 && cell.row >= 0) {
1976             if (scrollOrientation() == Qt::Vertical) {
1977                 startMovingAnim = (cell.row == m_layouter->itemRow(index));
1978             } else {
1979                 startMovingAnim = (cell.column == m_layouter->itemColumn(index));
1980             }
1981         }
1982     }
1983
1984     if (startMovingAnim) {
1985         m_animation->start(widget, KItemListViewAnimation::MovingAnimation, newPos);
1986         return true;
1987     }
1988
1989     m_animation->stop(widget);
1990     m_animation->start(widget, KItemListViewAnimation::CreateAnimation);
1991     return false;
1992 }
1993
1994 void KItemListView::emitOffsetChanges()
1995 {
1996     const qreal newScrollOffset = m_layouter->scrollOffset();
1997     if (m_oldScrollOffset != newScrollOffset) {
1998         Q_EMIT scrollOffsetChanged(newScrollOffset, m_oldScrollOffset);
1999         m_oldScrollOffset = newScrollOffset;
2000     }
2001
2002     const qreal newMaximumScrollOffset = m_layouter->maximumScrollOffset();
2003     if (m_oldMaximumScrollOffset != newMaximumScrollOffset) {
2004         Q_EMIT maximumScrollOffsetChanged(newMaximumScrollOffset, m_oldMaximumScrollOffset);
2005         m_oldMaximumScrollOffset = newMaximumScrollOffset;
2006     }
2007
2008     const qreal newItemOffset = m_layouter->itemOffset();
2009     if (m_oldItemOffset != newItemOffset) {
2010         Q_EMIT itemOffsetChanged(newItemOffset, m_oldItemOffset);
2011         m_oldItemOffset = newItemOffset;
2012     }
2013
2014     const qreal newMaximumItemOffset = m_layouter->maximumItemOffset();
2015     if (m_oldMaximumItemOffset != newMaximumItemOffset) {
2016         Q_EMIT maximumItemOffsetChanged(newMaximumItemOffset, m_oldMaximumItemOffset);
2017         m_oldMaximumItemOffset = newMaximumItemOffset;
2018     }
2019 }
2020
2021 KItemListWidget* KItemListView::createWidget(int index)
2022 {
2023     KItemListWidget* widget = widgetCreator()->create(this);
2024     widget->setFlag(QGraphicsItem::ItemStacksBehindParent);
2025
2026     m_visibleItems.insert(index, widget);
2027     m_visibleCells.insert(index, Cell());
2028     updateWidgetProperties(widget, index);
2029     initializeItemListWidget(widget);
2030     return widget;
2031 }
2032
2033 void KItemListView::recycleWidget(KItemListWidget* widget)
2034 {
2035     if (m_grouped) {
2036         recycleGroupHeaderForWidget(widget);
2037     }
2038
2039     const int index = widget->index();
2040     m_visibleItems.remove(index);
2041     m_visibleCells.remove(index);
2042
2043     widgetCreator()->recycle(widget);
2044 }
2045
2046 void KItemListView::setWidgetIndex(KItemListWidget* widget, int index)
2047 {
2048     const int oldIndex = widget->index();
2049     m_visibleItems.remove(oldIndex);
2050     m_visibleCells.remove(oldIndex);
2051
2052     m_visibleItems.insert(index, widget);
2053     m_visibleCells.insert(index, Cell());
2054
2055     widget->setIndex(index);
2056 }
2057
2058 void KItemListView::moveWidgetToIndex(KItemListWidget* widget, int index)
2059 {
2060     const int oldIndex = widget->index();
2061     const Cell oldCell = m_visibleCells.value(oldIndex);
2062
2063     setWidgetIndex(widget, index);
2064
2065     const Cell newCell(m_layouter->itemColumn(index), m_layouter->itemRow(index));
2066     const bool vertical = (scrollOrientation() == Qt::Vertical);
2067     const bool updateCell = (vertical  && oldCell.row    == newCell.row) ||
2068                             (!vertical && oldCell.column == newCell.column);
2069     if (updateCell) {
2070         m_visibleCells.insert(index, newCell);
2071     }
2072 }
2073
2074 void KItemListView::setLayouterSize(const QSizeF& size, SizeType sizeType)
2075 {
2076     switch (sizeType) {
2077     case LayouterSize: m_layouter->setSize(size); break;
2078     case ItemSize: m_layouter->setItemSize(size); break;
2079     default: break;
2080     }
2081 }
2082
2083 void KItemListView::updateWidgetProperties(KItemListWidget* widget, int index)
2084 {
2085     widget->setVisibleRoles(m_visibleRoles);
2086     updateWidgetColumnWidths(widget);
2087     widget->setStyleOption(m_styleOption);
2088
2089     const KItemListSelectionManager* selectionManager = m_controller->selectionManager();
2090
2091     // In SingleSelection mode (e.g., in the Places Panel), the current item is
2092     // always the selected item. It is not necessary to highlight the current item then.
2093     if (m_controller->selectionBehavior() != KItemListController::SingleSelection) {
2094         widget->setCurrent(index == selectionManager->currentItem());
2095     }
2096     widget->setSelected(selectionManager->isSelected(index));
2097     widget->setHovered(false);
2098     widget->setEnabledSelectionToggle(enabledSelectionToggles());
2099     widget->setIndex(index);
2100     widget->setData(m_model->data(index));
2101     widget->setSiblingsInformation(QBitArray());
2102     updateAlternateBackgroundForWidget(widget);
2103
2104     if (m_grouped) {
2105         updateGroupHeaderForWidget(widget);
2106     }
2107 }
2108
2109 void KItemListView::updateGroupHeaderForWidget(KItemListWidget* widget)
2110 {
2111     Q_ASSERT(m_grouped);
2112
2113     const int index = widget->index();
2114     if (!m_layouter->isFirstGroupItem(index)) {
2115         // The widget does not represent the first item of a group
2116         // and hence requires no header
2117         recycleGroupHeaderForWidget(widget);
2118         return;
2119     }
2120
2121     const QList<QPair<int, QVariant> > groups = model()->groups();
2122     if (groups.isEmpty() || !groupHeaderCreator()) {
2123         return;
2124     }
2125
2126     KItemListGroupHeader* groupHeader = m_visibleGroups.value(widget);
2127     if (!groupHeader) {
2128         groupHeader = groupHeaderCreator()->create(this);
2129         groupHeader->setParentItem(widget);
2130         m_visibleGroups.insert(widget, groupHeader);
2131         connect(widget, &KItemListWidget::geometryChanged, this, &KItemListView::slotGeometryOfGroupHeaderParentChanged);
2132     }
2133     Q_ASSERT(groupHeader->parentItem() == widget);
2134
2135     const int groupIndex = groupIndexForItem(index);
2136     Q_ASSERT(groupIndex >= 0);
2137     groupHeader->setData(groups.at(groupIndex).second);
2138     groupHeader->setRole(model()->sortRole());
2139     groupHeader->setStyleOption(m_styleOption);
2140     groupHeader->setScrollOrientation(scrollOrientation());
2141     groupHeader->setItemIndex(index);
2142
2143     groupHeader->show();
2144 }
2145
2146 void KItemListView::updateGroupHeaderLayout(KItemListWidget* widget)
2147 {
2148     KItemListGroupHeader* groupHeader = m_visibleGroups.value(widget);
2149     Q_ASSERT(groupHeader);
2150
2151     const int index = widget->index();
2152     const QRectF groupHeaderRect = m_layouter->groupHeaderRect(index);
2153     const QRectF itemRect = m_layouter->itemRect(index);
2154
2155     // The group-header is a child of the itemlist widget. Translate the
2156     // group header position to the relative position.
2157     if (scrollOrientation() == Qt::Vertical) {
2158         // In the vertical scroll orientation the group header should always span
2159         // the whole width no matter which temporary position the parent widget
2160         // has. In this case the x-position and width will be adjusted manually.
2161         const qreal x = -widget->x() - itemOffset();
2162         const qreal width = maximumItemOffset();
2163         groupHeader->setPos(x, -groupHeaderRect.height());
2164         groupHeader->resize(width, groupHeaderRect.size().height());
2165     } else {
2166         groupHeader->setPos(groupHeaderRect.x() - itemRect.x(), -widget->y());
2167         groupHeader->resize(groupHeaderRect.size());
2168     }
2169 }
2170
2171 void KItemListView::recycleGroupHeaderForWidget(KItemListWidget* widget)
2172 {
2173     KItemListGroupHeader* header = m_visibleGroups.value(widget);
2174     if (header) {
2175         header->setParentItem(nullptr);
2176         groupHeaderCreator()->recycle(header);
2177         m_visibleGroups.remove(widget);
2178         disconnect(widget, &KItemListWidget::geometryChanged, this, &KItemListView::slotGeometryOfGroupHeaderParentChanged);
2179     }
2180 }
2181
2182 void KItemListView::updateVisibleGroupHeaders()
2183 {
2184     Q_ASSERT(m_grouped);
2185     m_layouter->markAsDirty();
2186
2187     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2188     while (it.hasNext()) {
2189         it.next();
2190         updateGroupHeaderForWidget(it.value());
2191     }
2192 }
2193
2194 int KItemListView::groupIndexForItem(int index) const
2195 {
2196     Q_ASSERT(m_grouped);
2197
2198     const QList<QPair<int, QVariant> > groups = model()->groups();
2199     if (groups.isEmpty()) {
2200         return -1;
2201     }
2202
2203     int min = 0;
2204     int max = groups.count() - 1;
2205     int mid = 0;
2206     do {
2207         mid = (min + max) / 2;
2208         if (index > groups[mid].first) {
2209             min = mid + 1;
2210         } else {
2211             max = mid - 1;
2212         }
2213     } while (groups[mid].first != index && min <= max);
2214
2215     if (min > max) {
2216         while (groups[mid].first > index && mid > 0) {
2217             --mid;
2218         }
2219     }
2220
2221     return mid;
2222 }
2223
2224 void KItemListView::updateAlternateBackgrounds()
2225 {
2226     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2227     while (it.hasNext()) {
2228         it.next();
2229         updateAlternateBackgroundForWidget(it.value());
2230     }
2231 }
2232
2233 void KItemListView::updateAlternateBackgroundForWidget(KItemListWidget* widget)
2234 {
2235     bool enabled = useAlternateBackgrounds();
2236     if (enabled) {
2237         const int index = widget->index();
2238         enabled = (index & 0x1) > 0;
2239         if (m_grouped) {
2240             const int groupIndex = groupIndexForItem(index);
2241             if (groupIndex >= 0) {
2242                 const QList<QPair<int, QVariant> > groups = model()->groups();
2243                 const int indexOfFirstGroupItem = groups[groupIndex].first;
2244                 const int relativeIndex = index - indexOfFirstGroupItem;
2245                 enabled = (relativeIndex & 0x1) > 0;
2246             }
2247         }
2248     }
2249     widget->setAlternateBackground(enabled);
2250 }
2251
2252 bool KItemListView::useAlternateBackgrounds() const
2253 {
2254     return m_alternateBackgrounds && m_itemSize.isEmpty();
2255 }
2256
2257 QHash<QByteArray, qreal> KItemListView::preferredColumnWidths(const KItemRangeList& itemRanges) const
2258 {
2259     QElapsedTimer timer;
2260     timer.start();
2261
2262     QHash<QByteArray, qreal> widths;
2263
2264     // Calculate the minimum width for each column that is required
2265     // to show the headline unclipped.
2266     const QFontMetricsF fontMetrics(m_headerWidget->font());
2267     const int gripMargin   = m_headerWidget->style()->pixelMetric(QStyle::PM_HeaderGripMargin);
2268     const int headerMargin = m_headerWidget->style()->pixelMetric(QStyle::PM_HeaderMargin);
2269     for (const QByteArray& visibleRole : qAsConst(m_visibleRoles)) {
2270         const QString headerText = m_model->roleDescription(visibleRole);
2271         const qreal headerWidth = fontMetrics.horizontalAdvance(headerText) + gripMargin + headerMargin * 2;
2272         widths.insert(visibleRole, headerWidth);
2273     }
2274
2275     // Calculate the preferred column widths for each item and ignore values
2276     // smaller than the width for showing the headline unclipped.
2277     const KItemListWidgetCreatorBase* creator = widgetCreator();
2278     int calculatedItemCount = 0;
2279     bool maxTimeExceeded = false;
2280     for (const KItemRange& itemRange : itemRanges) {
2281         const int startIndex = itemRange.index;
2282         const int endIndex = startIndex + itemRange.count - 1;
2283
2284         for (int i = startIndex; i <= endIndex; ++i) {
2285             for (const QByteArray& visibleRole : qAsConst(m_visibleRoles)) {
2286                 qreal maxWidth = widths.value(visibleRole, 0);
2287                 const qreal width = creator->preferredRoleColumnWidth(visibleRole, i, this);
2288                 maxWidth = qMax(width, maxWidth);
2289                 widths.insert(visibleRole, maxWidth);
2290             }
2291
2292             if (calculatedItemCount > 100 && timer.elapsed() > 200) {
2293                 // When having several thousands of items calculating the sizes can get
2294                 // very expensive. We accept a possibly too small role-size in favour
2295                 // of having no blocking user interface.
2296                 maxTimeExceeded = true;
2297                 break;
2298             }
2299             ++calculatedItemCount;
2300         }
2301         if (maxTimeExceeded) {
2302             break;
2303         }
2304     }
2305
2306     return widths;
2307 }
2308
2309 void KItemListView::applyColumnWidthsFromHeader()
2310 {
2311     // Apply the new size to the layouter
2312     const qreal requiredWidth = columnWidthsSum() + m_headerWidget->leadingPadding();
2313     const QSizeF dynamicItemSize(qMax(size().width(), requiredWidth),
2314                                  m_itemSize.height());
2315     m_layouter->setItemSize(dynamicItemSize);
2316
2317     // Update the role sizes for all visible widgets
2318     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2319     while (it.hasNext()) {
2320         it.next();
2321         updateWidgetColumnWidths(it.value());
2322     }
2323 }
2324
2325 void KItemListView::updateWidgetColumnWidths(KItemListWidget* widget)
2326 {
2327     for (const QByteArray& role : qAsConst(m_visibleRoles)) {
2328         widget->setColumnWidth(role, m_headerWidget->columnWidth(role));
2329     }
2330     widget->setLeadingPadding(m_headerWidget->leadingPadding());
2331 }
2332
2333 void KItemListView::updatePreferredColumnWidths(const KItemRangeList& itemRanges)
2334 {
2335     Q_ASSERT(m_itemSize.isEmpty());
2336     const int itemCount = m_model->count();
2337     int rangesItemCount = 0;
2338     for (const KItemRange& range : itemRanges) {
2339         rangesItemCount += range.count;
2340     }
2341
2342     if (itemCount == rangesItemCount) {
2343         const QHash<QByteArray, qreal> preferredWidths = preferredColumnWidths(itemRanges);
2344         for (const QByteArray& role : qAsConst(m_visibleRoles)) {
2345             m_headerWidget->setPreferredColumnWidth(role, preferredWidths.value(role));
2346         }
2347     } else {
2348         // Only a sub range of the roles need to be determined.
2349         // The chances are good that the widths of the sub ranges
2350         // already fit into the available widths and hence no
2351         // expensive update might be required.
2352         bool changed = false;
2353
2354         const QHash<QByteArray, qreal> updatedWidths = preferredColumnWidths(itemRanges);
2355         QHashIterator<QByteArray, qreal> it(updatedWidths);
2356         while (it.hasNext()) {
2357             it.next();
2358             const QByteArray& role = it.key();
2359             const qreal updatedWidth = it.value();
2360             const qreal currentWidth = m_headerWidget->preferredColumnWidth(role);
2361             if (updatedWidth > currentWidth) {
2362                 m_headerWidget->setPreferredColumnWidth(role, updatedWidth);
2363                 changed = true;
2364             }
2365         }
2366
2367         if (!changed) {
2368             // All the updated sizes are smaller than the current sizes and no change
2369             // of the stretched roles-widths is required
2370             return;
2371         }
2372     }
2373
2374     if (m_headerWidget->automaticColumnResizing()) {
2375         applyAutomaticColumnWidths();
2376     }
2377 }
2378
2379 void KItemListView::updatePreferredColumnWidths()
2380 {
2381     if (m_model) {
2382         updatePreferredColumnWidths(KItemRangeList() << KItemRange(0, m_model->count()));
2383     }
2384 }
2385
2386 void KItemListView::applyAutomaticColumnWidths()
2387 {
2388     Q_ASSERT(m_itemSize.isEmpty());
2389     Q_ASSERT(m_headerWidget->automaticColumnResizing());
2390     if (m_visibleRoles.isEmpty()) {
2391         return;
2392     }
2393
2394     // Calculate the maximum size of an item by considering the
2395     // visible role sizes and apply them to the layouter. If the
2396     // size does not use the available view-size the size of the
2397     // first role will get stretched.
2398
2399     for (const QByteArray& role : qAsConst(m_visibleRoles)) {
2400         const qreal preferredWidth = m_headerWidget->preferredColumnWidth(role);
2401         m_headerWidget->setColumnWidth(role, preferredWidth);
2402     }
2403
2404     const QByteArray firstRole = m_visibleRoles.first();
2405     qreal firstColumnWidth = m_headerWidget->columnWidth(firstRole);
2406     QSizeF dynamicItemSize = m_itemSize;
2407
2408     qreal requiredWidth = columnWidthsSum() + m_headerWidget->leadingPadding();
2409     const qreal availableWidth = size().width();
2410     if (requiredWidth < availableWidth) {
2411         // Stretch the first column to use the whole remaining width
2412         firstColumnWidth += availableWidth - requiredWidth;
2413         m_headerWidget->setColumnWidth(firstRole, firstColumnWidth);
2414     } else if (requiredWidth > availableWidth && m_visibleRoles.count() > 1) {
2415         // Shrink the first column to be able to show as much other
2416         // columns as possible
2417         qreal shrinkedFirstColumnWidth = firstColumnWidth - requiredWidth + availableWidth;
2418
2419         // TODO: A proper calculation of the minimum width depends on the implementation
2420         // of KItemListWidget. Probably a kind of minimum size-hint should be introduced
2421         // later.
2422         const qreal minWidth = qMin(firstColumnWidth, qreal(m_styleOption.iconSize * 2 + 200));
2423         if (shrinkedFirstColumnWidth < minWidth) {
2424             shrinkedFirstColumnWidth = minWidth;
2425         }
2426
2427         m_headerWidget->setColumnWidth(firstRole, shrinkedFirstColumnWidth);
2428         requiredWidth -= firstColumnWidth - shrinkedFirstColumnWidth;
2429     }
2430
2431     dynamicItemSize.rwidth() = qMax(requiredWidth, availableWidth);
2432
2433     m_layouter->setItemSize(dynamicItemSize);
2434
2435     // Update the role sizes for all visible widgets
2436     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2437     while (it.hasNext()) {
2438         it.next();
2439         updateWidgetColumnWidths(it.value());
2440     }
2441 }
2442
2443 qreal KItemListView::columnWidthsSum() const
2444 {
2445     qreal widthsSum = 0;
2446     for (const QByteArray& role : qAsConst(m_visibleRoles)) {
2447         widthsSum += m_headerWidget->columnWidth(role);
2448     }
2449     return widthsSum;
2450 }
2451
2452 QRectF KItemListView::headerBoundaries() const
2453 {
2454     return m_headerWidget->isVisible() ? m_headerWidget->geometry() : QRectF();
2455 }
2456
2457 bool KItemListView::changesItemGridLayout(const QSizeF& newGridSize,
2458                                           const QSizeF& newItemSize,
2459                                           const QSizeF& newItemMargin) const
2460 {
2461     if (newItemSize.isEmpty() || newGridSize.isEmpty()) {
2462         return false;
2463     }
2464
2465     if (m_layouter->scrollOrientation() == Qt::Vertical) {
2466         const qreal itemWidth = m_layouter->itemSize().width();
2467         if (itemWidth > 0) {
2468             const int newColumnCount = itemsPerSize(newGridSize.width(),
2469                                                     newItemSize.width(),
2470                                                     newItemMargin.width());
2471             if (m_model->count() > newColumnCount) {
2472                 const int oldColumnCount = itemsPerSize(m_layouter->size().width(),
2473                                                         itemWidth,
2474                                                         m_layouter->itemMargin().width());
2475                 return oldColumnCount != newColumnCount;
2476             }
2477         }
2478     } else {
2479         const qreal itemHeight = m_layouter->itemSize().height();
2480         if (itemHeight > 0) {
2481             const int newRowCount = itemsPerSize(newGridSize.height(),
2482                                                  newItemSize.height(),
2483                                                  newItemMargin.height());
2484             if (m_model->count() > newRowCount) {
2485                 const int oldRowCount = itemsPerSize(m_layouter->size().height(),
2486                                                      itemHeight,
2487                                                      m_layouter->itemMargin().height());
2488                 return oldRowCount != newRowCount;
2489             }
2490         }
2491     }
2492
2493     return false;
2494 }
2495
2496 bool KItemListView::animateChangedItemCount(int changedItemCount) const
2497 {
2498     if (m_itemSize.isEmpty()) {
2499         // We have only columns or only rows, but no grid: An animation is usually
2500         // welcome when inserting or removing items.
2501         return !supportsItemExpanding();
2502     }
2503
2504     if (m_layouter->size().isEmpty() || m_layouter->itemSize().isEmpty()) {
2505         return false;
2506     }
2507
2508     const int maximum = (scrollOrientation() == Qt::Vertical)
2509                         ? m_layouter->size().width()  / m_layouter->itemSize().width()
2510                         : m_layouter->size().height() / m_layouter->itemSize().height();
2511     // Only animate if up to 2/3 of a row or column are inserted or removed
2512     return changedItemCount <= maximum * 2 / 3;
2513 }
2514
2515
2516 bool KItemListView::scrollBarRequired(const QSizeF& size) const
2517 {
2518     const QSizeF oldSize = m_layouter->size();
2519
2520     m_layouter->setSize(size);
2521     const qreal maxOffset = m_layouter->maximumScrollOffset();
2522     m_layouter->setSize(oldSize);
2523
2524     return m_layouter->scrollOrientation() == Qt::Vertical ? maxOffset > size.height()
2525                                                            : maxOffset > size.width();
2526 }
2527
2528 int KItemListView::showDropIndicator(const QPointF& pos)
2529 {
2530     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2531     while (it.hasNext()) {
2532         it.next();
2533         const KItemListWidget* widget = it.value();
2534
2535         const QPointF mappedPos = widget->mapFromItem(this, pos);
2536         const QRectF rect = itemRect(widget->index());
2537         if (mappedPos.y() >= 0 && mappedPos.y() <= rect.height()) {
2538             if (m_model->supportsDropping(widget->index())) {
2539                 // Keep 30% of the rectangle as the gap instead of always having a fixed gap
2540                 const int gap = qMax(qreal(4.0), qreal(0.3) * rect.height());
2541                 if (mappedPos.y() >= gap && mappedPos.y() <= rect.height() - gap) {
2542                     return -1;
2543                 }
2544             }
2545
2546             const bool isAboveItem = (mappedPos.y () < rect.height() / 2);
2547             const qreal y = isAboveItem ? rect.top() : rect.bottom();
2548
2549             const QRectF draggingInsertIndicator(rect.left(), y, rect.width(), 1);
2550             if (m_dropIndicator != draggingInsertIndicator) {
2551                 m_dropIndicator = draggingInsertIndicator;
2552                 update();
2553             }
2554
2555             int index = widget->index();
2556             if (!isAboveItem) {
2557                 ++index;
2558             }
2559             return index;
2560         }
2561     }
2562
2563     const QRectF firstItemRect = itemRect(firstVisibleIndex());
2564     return (pos.y() <= firstItemRect.top()) ? 0 : -1;
2565 }
2566
2567 void KItemListView::hideDropIndicator()
2568 {
2569     if (!m_dropIndicator.isNull()) {
2570         m_dropIndicator = QRectF();
2571         update();
2572     }
2573 }
2574
2575 void KItemListView::updateGroupHeaderHeight()
2576 {
2577     qreal groupHeaderHeight = m_styleOption.fontMetrics.height();
2578     qreal groupHeaderMargin = 0;
2579
2580     if (scrollOrientation() == Qt::Horizontal) {
2581         // The vertical margin above and below the header should be
2582         // equal to the horizontal margin, not the vertical margin
2583         // from m_styleOption.
2584         groupHeaderHeight += 2 * m_styleOption.horizontalMargin;
2585         groupHeaderMargin = m_styleOption.horizontalMargin;
2586     } else if (m_itemSize.isEmpty()){
2587         groupHeaderHeight += 4 * m_styleOption.padding;
2588         groupHeaderMargin = m_styleOption.iconSize / 2;
2589     } else {
2590         groupHeaderHeight += 2 * m_styleOption.padding + m_styleOption.verticalMargin;
2591         groupHeaderMargin = m_styleOption.iconSize / 4;
2592     }
2593     m_layouter->setGroupHeaderHeight(groupHeaderHeight);
2594     m_layouter->setGroupHeaderMargin(groupHeaderMargin);
2595
2596     updateVisibleGroupHeaders();
2597 }
2598
2599 void KItemListView::updateSiblingsInformation(int firstIndex, int lastIndex)
2600 {
2601     if (!supportsItemExpanding() || !m_model) {
2602         return;
2603     }
2604
2605     if (firstIndex < 0 || lastIndex < 0) {
2606         firstIndex = m_layouter->firstVisibleIndex();
2607         lastIndex  = m_layouter->lastVisibleIndex();
2608     } else {
2609         const bool isRangeVisible = (firstIndex <= m_layouter->lastVisibleIndex() &&
2610                                      lastIndex  >= m_layouter->firstVisibleIndex());
2611         if (!isRangeVisible) {
2612             return;
2613         }
2614     }
2615
2616     int previousParents = 0;
2617     QBitArray previousSiblings;
2618
2619     // The rootIndex describes the first index where the siblings get
2620     // calculated from. For the calculation the upper most parent item
2621     // is required. For performance reasons it is checked first whether
2622     // the visible items before or after the current range already
2623     // contain a siblings information which can be used as base.
2624     int rootIndex = firstIndex;
2625
2626     KItemListWidget* widget = m_visibleItems.value(firstIndex - 1);
2627     if (!widget) {
2628         // There is no visible widget before the range, check whether there
2629         // is one after the range:
2630         widget = m_visibleItems.value(lastIndex + 1);
2631         if (widget) {
2632             // The sibling information of the widget may only be used if
2633             // all items of the range have the same number of parents.
2634             const int parents = m_model->expandedParentsCount(lastIndex + 1);
2635             for (int i = lastIndex; i >= firstIndex; --i) {
2636                 if (m_model->expandedParentsCount(i) != parents) {
2637                     widget = nullptr;
2638                     break;
2639                 }
2640             }
2641         }
2642     }
2643
2644     if (widget) {
2645         // Performance optimization: Use the sibling information of the visible
2646         // widget beside the given range.
2647         previousSiblings = widget->siblingsInformation();
2648         if (previousSiblings.isEmpty()) {
2649             return;
2650         }
2651         previousParents = previousSiblings.count() - 1;
2652         previousSiblings.truncate(previousParents);
2653     } else {
2654         // Potentially slow path: Go back to the upper most parent of firstIndex
2655         // to be able to calculate the initial value for the siblings.
2656         while (rootIndex > 0 && m_model->expandedParentsCount(rootIndex) > 0) {
2657             --rootIndex;
2658         }
2659     }
2660
2661     Q_ASSERT(previousParents >= 0);
2662     for (int i = rootIndex; i <= lastIndex; ++i) {
2663         // Update the parent-siblings in case if the current item represents
2664         // a child or an upper parent.
2665         const int currentParents = m_model->expandedParentsCount(i);
2666         Q_ASSERT(currentParents >= 0);
2667         if (previousParents < currentParents) {
2668             previousParents = currentParents;
2669             previousSiblings.resize(currentParents);
2670             previousSiblings.setBit(currentParents - 1, hasSiblingSuccessor(i - 1));
2671         } else if (previousParents > currentParents) {
2672             previousParents = currentParents;
2673             previousSiblings.truncate(currentParents);
2674         }
2675
2676         if (i >= firstIndex) {
2677             // The index represents a visible item. Apply the parent-siblings
2678             // and update the sibling of the current item.
2679             KItemListWidget* widget = m_visibleItems.value(i);
2680             if (!widget) {
2681                 continue;
2682             }
2683
2684             QBitArray siblings = previousSiblings;
2685             siblings.resize(siblings.count() + 1);
2686             siblings.setBit(siblings.count() - 1, hasSiblingSuccessor(i));
2687
2688             widget->setSiblingsInformation(siblings);
2689         }
2690     }
2691 }
2692
2693 bool KItemListView::hasSiblingSuccessor(int index) const
2694 {
2695     bool hasSuccessor = false;
2696     const int parentsCount = m_model->expandedParentsCount(index);
2697     int successorIndex = index + 1;
2698
2699     // Search the next sibling
2700     const int itemCount = m_model->count();
2701     while (successorIndex < itemCount) {
2702         const int currentParentsCount = m_model->expandedParentsCount(successorIndex);
2703         if (currentParentsCount == parentsCount) {
2704             hasSuccessor = true;
2705             break;
2706         } else if (currentParentsCount < parentsCount) {
2707             break;
2708         }
2709         ++successorIndex;
2710     }
2711
2712     if (m_grouped && hasSuccessor) {
2713         // If the sibling is part of another group, don't mark it as
2714         // successor as the group header is between the sibling connections.
2715         for (int i = index + 1; i <= successorIndex; ++i) {
2716             if (m_layouter->isFirstGroupItem(i)) {
2717                 hasSuccessor = false;
2718                 break;
2719             }
2720         }
2721     }
2722
2723     return hasSuccessor;
2724 }
2725
2726 void KItemListView::disconnectRoleEditingSignals(int index)
2727 {
2728     KStandardItemListWidget* widget = qobject_cast<KStandardItemListWidget *>(m_visibleItems.value(index));
2729     if (!widget) {
2730         return;
2731     }
2732
2733     disconnect(widget, &KItemListWidget::roleEditingCanceled, this, nullptr);
2734     disconnect(widget, &KItemListWidget::roleEditingFinished, this, nullptr);
2735     disconnect(this, &KItemListView::scrollOffsetChanged, widget, nullptr);
2736 }
2737
2738 int KItemListView::calculateAutoScrollingIncrement(int pos, int range, int oldInc)
2739 {
2740     int inc = 0;
2741
2742     const int minSpeed = 4;
2743     const int maxSpeed = 128;
2744     const int speedLimiter = 96;
2745     const int autoScrollBorder = 64;
2746
2747     // Limit the increment that is allowed to be added in comparison to 'oldInc'.
2748     // This assures that the autoscrolling speed grows gradually.
2749     const int incLimiter = 1;
2750
2751     if (pos < autoScrollBorder) {
2752         inc = -minSpeed + qAbs(pos - autoScrollBorder) * (pos - autoScrollBorder) / speedLimiter;
2753         inc = qMax(inc, -maxSpeed);
2754         inc = qMax(inc, oldInc - incLimiter);
2755     } else if (pos > range - autoScrollBorder) {
2756         inc = minSpeed + qAbs(pos - range + autoScrollBorder) * (pos - range + autoScrollBorder) / speedLimiter;
2757         inc = qMin(inc, maxSpeed);
2758         inc = qMin(inc, oldInc + incLimiter);
2759     }
2760
2761     return inc;
2762 }
2763
2764 int KItemListView::itemsPerSize(qreal size, qreal itemSize, qreal itemMargin)
2765 {
2766     const qreal availableSize = size - itemMargin;
2767     const int count = availableSize / (itemSize + itemMargin);
2768     return count;
2769 }
2770
2771
2772
2773 KItemListCreatorBase::~KItemListCreatorBase()
2774 {
2775     qDeleteAll(m_recycleableWidgets);
2776     qDeleteAll(m_createdWidgets);
2777 }
2778
2779 void KItemListCreatorBase::addCreatedWidget(QGraphicsWidget* widget)
2780 {
2781     m_createdWidgets.insert(widget);
2782 }
2783
2784 void KItemListCreatorBase::pushRecycleableWidget(QGraphicsWidget* widget)
2785 {
2786     Q_ASSERT(m_createdWidgets.contains(widget));
2787     m_createdWidgets.remove(widget);
2788
2789     if (m_recycleableWidgets.count() < 100) {
2790         m_recycleableWidgets.append(widget);
2791         widget->setVisible(false);
2792     } else {
2793         delete widget;
2794     }
2795 }
2796
2797 QGraphicsWidget* KItemListCreatorBase::popRecycleableWidget()
2798 {
2799     if (m_recycleableWidgets.isEmpty()) {
2800         return nullptr;
2801     }
2802
2803     QGraphicsWidget* widget = m_recycleableWidgets.takeLast();
2804     m_createdWidgets.insert(widget);
2805     return widget;
2806 }
2807
2808 KItemListWidgetCreatorBase::~KItemListWidgetCreatorBase()
2809 {
2810 }
2811
2812 void KItemListWidgetCreatorBase::recycle(KItemListWidget* widget)
2813 {
2814     widget->setParentItem(nullptr);
2815     widget->setOpacity(1.0);
2816     pushRecycleableWidget(widget);
2817 }
2818
2819 KItemListGroupHeaderCreatorBase::~KItemListGroupHeaderCreatorBase()
2820 {
2821 }
2822
2823 void KItemListGroupHeaderCreatorBase::recycle(KItemListGroupHeader* header)
2824 {
2825     header->setOpacity(1.0);
2826     pushRecycleableWidget(header);
2827 }
2828