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