src/kitemviews/kitemlistview.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Peter Penz <peter.penz19@gmail.com>             *
   3  *                                                                         *
   4  *   Based on the Itemviews NG project from Trolltech Labs:                *
   5  *   http://qt.gitorious.org/qt-labs/itemviews-ng                          *
   6  *                                                                         *
   7  *   This program is free software; you can redistribute it and/or modify  *
   8  *   it under the terms of the GNU General Public License as published by  *
   9  *   the Free Software Foundation; either version 2 of the License, or     *
  10  *   (at your option) any later version.                                   *
  11  *                                                                         *
  12  *   This program is distributed in the hope that it will be useful,       *
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  15  *   GNU General Public License for more details.                          *
  16  *                                                                         *
  17  *   You should have received a copy of the GNU General Public License     *
  18  *   along with this program; if not, write to the                         *
  19  *   Free Software Foundation, Inc.,                                       *
  20  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  21  ***************************************************************************/
  22
  23 #include "kitemlistview.h"
  24
  25 #include <KDebug>
  26 #include "kitemlistcontainer.h"
  27 #include "kitemlistcontroller.h"
  28 #include "kitemlistheader.h"
  29 #include "kitemlistselectionmanager.h"
  30 #include "kitemlistwidget.h"
  31
  32 #include "private/kitemlistheaderwidget.h"
  33 #include "private/kitemlistrubberband.h"
  34 #include "private/kitemlistsizehintresolver.h"
  35 #include "private/kitemlistviewlayouter.h"
  36 #include "private/kitemlistviewanimation.h"
  37
  38 #include <QCursor>
  39 #include <QGraphicsSceneMouseEvent>
  40 #include <QGraphicsView>
  41 #include <QPainter>
  42 #include <QPropertyAnimation>
  43 #include <QStyle>
  44 #include <QStyleOptionRubberBand>
  45 #include <QTimer>
  46
  47 #include <algorithm>
  48
  49 #include "kitemlistviewaccessible.h"
  50
  51 namespace {
  52     // Time in ms until reaching the autoscroll margin triggers
  53     // an initial autoscrolling
  54     const int InitialAutoScrollDelay = 700;
  55
  56     // Delay in ms for triggering the next autoscroll
  57     const int RepeatingAutoScrollDelay = 1000 / 60;
  58 }
  59
  60 #ifndef QT_NO_ACCESSIBILITY
  61 QAccessibleInterface* accessibleInterfaceFactory(const QString &key, QObject *object)
  62 {
  63     Q_UNUSED(key)
  64
  65     if (KItemListContainer* container = qobject_cast<KItemListContainer*>(object)) {
  66         return new KItemListContainerAccessible(container);
  67     } else if (KItemListView* view = qobject_cast<KItemListView*>(object)) {
  68         return new KItemListViewAccessible(view);
  69     }
  70
  71     return 0;
  72 }
  73 #endif
  74
  75 KItemListView::KItemListView(QGraphicsWidget* parent) :
  76     QGraphicsWidget(parent),
  77     m_enabledSelectionToggles(false),
  78     m_grouped(false),
  79     m_supportsItemExpanding(false),
  80     m_editingRole(false),
  81     m_activeTransactions(0),
  82     m_endTransactionAnimationHint(Animation),
  83     m_itemSize(),
  84     m_controller(0),
  85     m_model(0),
  86     m_visibleRoles(),
  87     m_widgetCreator(0),
  88     m_groupHeaderCreator(0),
  89     m_styleOption(),
  90     m_visibleItems(),
  91     m_visibleGroups(),
  92     m_visibleCells(),
  93     m_sizeHintResolver(0),
  94     m_layouter(0),
  95     m_animation(0),
  96     m_layoutTimer(0),
  97     m_oldScrollOffset(0),
  98     m_oldMaximumScrollOffset(0),
  99     m_oldItemOffset(0),
 100     m_oldMaximumItemOffset(0),
 101     m_skipAutoScrollForRubberBand(false),
 102     m_rubberBand(0),
 103     m_mousePos(),
 104     m_autoScrollIncrement(0),
 105     m_autoScrollTimer(0),
 106     m_header(0),
 107     m_headerWidget(0),
 108     m_dropIndicator()
 109 {
 110     setAcceptHoverEvents(true);
 111
 112     m_sizeHintResolver = new KItemListSizeHintResolver(this);
 113
 114     m_layouter = new KItemListViewLayouter(m_sizeHintResolver, this);
 115
 116     m_animation = new KItemListViewAnimation(this);
 117     connect(m_animation, SIGNAL(finished(QGraphicsWidget*,KItemListViewAnimation::AnimationType)),
 118             this, SLOT(slotAnimationFinished(QGraphicsWidget*,KItemListViewAnimation::AnimationType)));
 119
 120     m_layoutTimer = new QTimer(this);
 121     m_layoutTimer->setInterval(300);
 122     m_layoutTimer->setSingleShot(true);
 123     connect(m_layoutTimer, SIGNAL(timeout()), this, SLOT(slotLayoutTimerFinished()));
 124
 125     m_rubberBand = new KItemListRubberBand(this);
 126     connect(m_rubberBand, SIGNAL(activationChanged(bool)), this, SLOT(slotRubberBandActivationChanged(bool)));
 127
 128     m_headerWidget = new KItemListHeaderWidget(this);
 129     m_headerWidget->setVisible(false);
 130
 131     m_header = new KItemListHeader(this);
 132
 133 #ifndef QT_NO_ACCESSIBILITY
 134     QAccessible::installFactory(accessibleInterfaceFactory);
 135 #endif
 136
 137 }
 138
 139 KItemListView::~KItemListView()
 140 {
 141     // The group headers are children of the widgets created by
 142     // widgetCreator(). So it is mandatory to delete the group headers
 143     // first.
 144     delete m_groupHeaderCreator;
 145     m_groupHeaderCreator = 0;
 146
 147     delete m_widgetCreator;
 148     m_widgetCreator = 0;
 149
 150     delete m_sizeHintResolver;
 151     m_sizeHintResolver = 0;
 152 }
 153
 154 void KItemListView::setScrollOffset(qreal offset)
 155 {
 156     if (offset < 0) {
 157         offset = 0;
 158     }
 159
 160     const qreal previousOffset = m_layouter->scrollOffset();
 161     if (offset == previousOffset) {
 162         return;
 163     }
 164
 165     m_layouter->setScrollOffset(offset);
 166     m_animation->setScrollOffset(offset);
 167
 168     // Don't check whether the m_layoutTimer is active: Changing the
 169     // scroll offset must always trigger a synchronous layout, otherwise
 170     // the smooth-scrolling might get jerky.
 171     doLayout(NoAnimation);
 172     onScrollOffsetChanged(offset, previousOffset);
 173 }
 174
 175 qreal KItemListView::scrollOffset() const
 176 {
 177     return m_layouter->scrollOffset();
 178 }
 179
 180 qreal KItemListView::maximumScrollOffset() const
 181 {
 182     return m_layouter->maximumScrollOffset();
 183 }
 184
 185 void KItemListView::setItemOffset(qreal offset)
 186 {
 187     if (m_layouter->itemOffset() == offset) {
 188         return;
 189     }
 190
 191     m_layouter->setItemOffset(offset);
 192     if (m_headerWidget->isVisible()) {
 193         m_headerWidget->setOffset(offset);
 194     }
 195
 196     // Don't check whether the m_layoutTimer is active: Changing the
 197     // item offset must always trigger a synchronous layout, otherwise
 198     // the smooth-scrolling might get jerky.
 199     doLayout(NoAnimation);
 200 }
 201
 202 qreal KItemListView::itemOffset() const
 203 {
 204     return m_layouter->itemOffset();
 205 }
 206
 207 qreal KItemListView::maximumItemOffset() const
 208 {
 209     return m_layouter->maximumItemOffset();
 210 }
 211
 212 int KItemListView::maximumVisibleItems() const
 213 {
 214     return m_layouter->maximumVisibleItems();
 215 }
 216
 217 void KItemListView::setVisibleRoles(const QList<QByteArray>& roles)
 218 {
 219     const QList<QByteArray> previousRoles = m_visibleRoles;
 220     m_visibleRoles = roles;
 221     onVisibleRolesChanged(roles, previousRoles);
 222
 223     m_sizeHintResolver->clearCache();
 224     m_layouter->markAsDirty();
 225
 226     if (m_itemSize.isEmpty()) {
 227         m_headerWidget->setColumns(roles);
 228         updatePreferredColumnWidths();
 229         if (!m_headerWidget->automaticColumnResizing()) {
 230             // The column-width of new roles are still 0. Apply the preferred
 231             // column-width as default with.
 232             foreach (const QByteArray& role, m_visibleRoles) {
 233                 if (m_headerWidget->columnWidth(role) == 0) {
 234                     const qreal width = m_headerWidget->preferredColumnWidth(role);
 235                     m_headerWidget->setColumnWidth(role, width);
 236                 }
 237             }
 238
 239             applyColumnWidthsFromHeader();
 240         }
 241     }
 242
 243     const bool alternateBackgroundsChanged = m_itemSize.isEmpty() &&
 244                                              ((roles.count() > 1 && previousRoles.count() <= 1) ||
 245                                               (roles.count() <= 1 && previousRoles.count() > 1));
 246
 247     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 248     while (it.hasNext()) {
 249         it.next();
 250         KItemListWidget* widget = it.value();
 251         widget->setVisibleRoles(roles);
 252         if (alternateBackgroundsChanged) {
 253             updateAlternateBackgroundForWidget(widget);
 254         }
 255     }
 256
 257     doLayout(NoAnimation);
 258 }
 259
 260 QList<QByteArray> KItemListView::visibleRoles() const
 261 {
 262     return m_visibleRoles;
 263 }
 264
 265 void KItemListView::setAutoScroll(bool enabled)
 266 {
 267     if (enabled && !m_autoScrollTimer) {
 268         m_autoScrollTimer = new QTimer(this);
 269         m_autoScrollTimer->setSingleShot(true);
 270         connect(m_autoScrollTimer, SIGNAL(timeout()), this, SLOT(triggerAutoScrolling()));
 271         m_autoScrollTimer->start(InitialAutoScrollDelay);
 272     } else if (!enabled && m_autoScrollTimer) {
 273         delete m_autoScrollTimer;
 274         m_autoScrollTimer = 0;
 275     }
 276 }
 277
 278 bool KItemListView::autoScroll() const
 279 {
 280     return m_autoScrollTimer != 0;
 281 }
 282
 283 void KItemListView::setEnabledSelectionToggles(bool enabled)
 284 {
 285     if (m_enabledSelectionToggles != enabled) {
 286         m_enabledSelectionToggles = enabled;
 287
 288         QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 289         while (it.hasNext()) {
 290             it.next();
 291             it.value()->setEnabledSelectionToggle(enabled);
 292         }
 293     }
 294 }
 295
 296 bool KItemListView::enabledSelectionToggles() const
 297 {
 298     return m_enabledSelectionToggles;
 299 }
 300
 301 KItemListController* KItemListView::controller() const
 302 {
 303     return m_controller;
 304 }
 305
 306 KItemModelBase* KItemListView::model() const
 307 {
 308     return m_model;
 309 }
 310
 311 void KItemListView::setWidgetCreator(KItemListWidgetCreatorBase* widgetCreator)
 312 {
 313     if (m_widgetCreator) {
 314         delete m_widgetCreator;
 315     }
 316     m_widgetCreator = widgetCreator;
 317 }
 318
 319 KItemListWidgetCreatorBase* KItemListView::widgetCreator() const
 320 {
 321     if (!m_widgetCreator) {
 322         m_widgetCreator = defaultWidgetCreator();
 323     }
 324     return m_widgetCreator;
 325 }
 326
 327 void KItemListView::setGroupHeaderCreator(KItemListGroupHeaderCreatorBase* groupHeaderCreator)
 328 {
 329     if (m_groupHeaderCreator) {
 330         delete m_groupHeaderCreator;
 331     }
 332     m_groupHeaderCreator = groupHeaderCreator;
 333 }
 334
 335 KItemListGroupHeaderCreatorBase* KItemListView::groupHeaderCreator() const
 336 {
 337     if (!m_groupHeaderCreator) {
 338         m_groupHeaderCreator = defaultGroupHeaderCreator();
 339     }
 340     return m_groupHeaderCreator;
 341 }
 342
 343 QSizeF KItemListView::itemSize() const
 344 {
 345     return m_itemSize;
 346 }
 347
 348 const KItemListStyleOption& KItemListView::styleOption() const
 349 {
 350     return m_styleOption;
 351 }
 352
 353 void KItemListView::setGeometry(const QRectF& rect)
 354 {
 355     QGraphicsWidget::setGeometry(rect);
 356
 357     if (!m_model) {
 358         return;
 359     }
 360
 361     const QSizeF newSize = rect.size();
 362     if (m_itemSize.isEmpty()) {
 363         m_headerWidget->resize(rect.width(), m_headerWidget->size().height());
 364         if (m_headerWidget->automaticColumnResizing()) {
 365             applyAutomaticColumnWidths();
 366         } else {
 367             const qreal requiredWidth = columnWidthsSum();
 368             const QSizeF dynamicItemSize(qMax(newSize.width(), requiredWidth),
 369                                          m_itemSize.height());
 370             m_layouter->setItemSize(dynamicItemSize);
 371         }
 372
 373         // Triggering a synchronous layout is fine from a performance point of view,
 374         // as with dynamic item sizes no moving animation must be done.
 375         m_layouter->setSize(newSize);
 376         doLayout(NoAnimation);
 377     } else {
 378         const bool animate = !changesItemGridLayout(newSize,
 379                                                     m_layouter->itemSize(),
 380                                                     m_layouter->itemMargin());
 381         m_layouter->setSize(newSize);
 382
 383         if (animate) {
 384             // Trigger an asynchronous relayout with m_layoutTimer to prevent
 385             // performance bottlenecks. If the timer is exceeded, an animated layout
 386             // will be triggered.
 387             if (!m_layoutTimer->isActive()) {
 388                 m_layoutTimer->start();
 389             }
 390         } else {
 391             m_layoutTimer->stop();
 392             doLayout(NoAnimation);
 393         }
 394     }
 395 }
 396
 397 qreal KItemListView::verticalPageStep() const
 398 {
 399     qreal headerHeight = 0;
 400     if (m_headerWidget->isVisible()) {
 401         headerHeight = m_headerWidget->size().height();
 402     }
 403     return size().height() - headerHeight;
 404 }
 405
 406 int KItemListView::itemAt(const QPointF& pos) const
 407 {
 408     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 409     while (it.hasNext()) {
 410         it.next();
 411
 412         const KItemListWidget* widget = it.value();
 413         const QPointF mappedPos = widget->mapFromItem(this, pos);
 414         if (widget->contains(mappedPos)) {
 415             return it.key();
 416         }
 417     }
 418
 419     return -1;
 420 }
 421
 422 bool KItemListView::isAboveSelectionToggle(int index, const QPointF& pos) const
 423 {
 424     if (!m_enabledSelectionToggles) {
 425         return false;
 426     }
 427
 428     const KItemListWidget* widget = m_visibleItems.value(index);
 429     if (widget) {
 430         const QRectF selectionToggleRect = widget->selectionToggleRect();
 431         if (!selectionToggleRect.isEmpty()) {
 432             const QPointF mappedPos = widget->mapFromItem(this, pos);
 433             return selectionToggleRect.contains(mappedPos);
 434         }
 435     }
 436     return false;
 437 }
 438
 439 bool KItemListView::isAboveExpansionToggle(int index, const QPointF& pos) const
 440 {
 441     const KItemListWidget* widget = m_visibleItems.value(index);
 442     if (widget) {
 443         const QRectF expansionToggleRect = widget->expansionToggleRect();
 444         if (!expansionToggleRect.isEmpty()) {
 445             const QPointF mappedPos = widget->mapFromItem(this, pos);
 446             return expansionToggleRect.contains(mappedPos);
 447         }
 448     }
 449     return false;
 450 }
 451
 452 int KItemListView::firstVisibleIndex() const
 453 {
 454     return m_layouter->firstVisibleIndex();
 455 }
 456
 457 int KItemListView::lastVisibleIndex() const
 458 {
 459     return m_layouter->lastVisibleIndex();
 460 }
 461
 462 void KItemListView::calculateItemSizeHints(QVector<QSizeF>& sizeHints) const
 463 {
 464     widgetCreator()->calculateItemSizeHints(sizeHints, this);
 465 }
 466
 467 void KItemListView::setSupportsItemExpanding(bool supportsExpanding)
 468 {
 469     if (m_supportsItemExpanding != supportsExpanding) {
 470         m_supportsItemExpanding = supportsExpanding;
 471         updateSiblingsInformation();
 472         onSupportsItemExpandingChanged(supportsExpanding);
 473     }
 474 }
 475
 476 bool KItemListView::supportsItemExpanding() const
 477 {
 478     return m_supportsItemExpanding;
 479 }
 480
 481 QRectF KItemListView::itemRect(int index) const
 482 {
 483     return m_layouter->itemRect(index);
 484 }
 485
 486 QRectF KItemListView::itemContextRect(int index) const
 487 {
 488     QRectF contextRect;
 489
 490     const KItemListWidget* widget = m_visibleItems.value(index);
 491     if (widget) {
 492         contextRect = widget->iconRect() | widget->textRect();
 493         contextRect.translate(itemRect(index).topLeft());
 494     }
 495
 496     return contextRect;
 497 }
 498
 499 void KItemListView::scrollToItem(int index)
 500 {
 501     QRectF viewGeometry = geometry();
 502     if (m_headerWidget->isVisible()) {
 503         const qreal headerHeight = m_headerWidget->size().height();
 504         viewGeometry.adjust(0, headerHeight, 0, 0);
 505     }
 506     QRectF currentRect = itemRect(index);
 507
 508     // Fix for Bug 311099 - View the underscore when using Ctrl + PagDown
 509     currentRect.adjust(-m_styleOption.horizontalMargin, -m_styleOption.verticalMargin,
 510                         m_styleOption.horizontalMargin,  m_styleOption.verticalMargin);
 511
 512     if (!viewGeometry.contains(currentRect)) {
 513         qreal newOffset = scrollOffset();
 514         if (scrollOrientation() == Qt::Vertical) {
 515             if (currentRect.top() < viewGeometry.top()) {
 516                 newOffset += currentRect.top() - viewGeometry.top();
 517             } else if (currentRect.bottom() > viewGeometry.bottom()) {
 518                 newOffset += currentRect.bottom() - viewGeometry.bottom();
 519             }
 520         } else {
 521             if (currentRect.left() < viewGeometry.left()) {
 522                 newOffset += currentRect.left() - viewGeometry.left();
 523             } else if (currentRect.right() > viewGeometry.right()) {
 524                 newOffset += currentRect.right() - viewGeometry.right();
 525             }
 526         }
 527
 528         if (newOffset != scrollOffset()) {
 529             emit scrollTo(newOffset);
 530         }
 531     }
 532 }
 533
 534 void KItemListView::beginTransaction()
 535 {
 536     ++m_activeTransactions;
 537     if (m_activeTransactions == 1) {
 538         onTransactionBegin();
 539     }
 540 }
 541
 542 void KItemListView::endTransaction()
 543 {
 544     --m_activeTransactions;
 545     if (m_activeTransactions < 0) {
 546         m_activeTransactions = 0;
 547         kWarning() << "Mismatch between beginTransaction()/endTransaction()";
 548     }
 549
 550     if (m_activeTransactions == 0) {
 551         onTransactionEnd();
 552         doLayout(m_endTransactionAnimationHint);
 553         m_endTransactionAnimationHint = Animation;
 554     }
 555 }
 556
 557 bool KItemListView::isTransactionActive() const
 558 {
 559     return m_activeTransactions > 0;
 560 }
 561
 562 void KItemListView::setHeaderVisible(bool visible)
 563 {
 564     if (visible && !m_headerWidget->isVisible()) {
 565         QStyleOptionHeader option;
 566         const QSize headerSize = style()->sizeFromContents(QStyle::CT_HeaderSection,
 567                                                            &option, QSize());
 568
 569         m_headerWidget->setPos(0, 0);
 570         m_headerWidget->resize(size().width(), headerSize.height());
 571         m_headerWidget->setModel(m_model);
 572         m_headerWidget->setColumns(m_visibleRoles);
 573         m_headerWidget->setZValue(1);
 574
 575         connect(m_headerWidget, SIGNAL(columnWidthChanged(QByteArray,qreal,qreal)),
 576                 this, SLOT(slotHeaderColumnWidthChanged(QByteArray,qreal,qreal)));
 577         connect(m_headerWidget, SIGNAL(columnMoved(QByteArray,int,int)),
 578                 this, SLOT(slotHeaderColumnMoved(QByteArray,int,int)));
 579         connect(m_headerWidget, SIGNAL(sortOrderChanged(Qt::SortOrder,Qt::SortOrder)),
 580                 this, SIGNAL(sortOrderChanged(Qt::SortOrder,Qt::SortOrder)));
 581         connect(m_headerWidget, SIGNAL(sortRoleChanged(QByteArray,QByteArray)),
 582                 this, SIGNAL(sortRoleChanged(QByteArray,QByteArray)));
 583
 584         m_layouter->setHeaderHeight(headerSize.height());
 585         m_headerWidget->setVisible(true);
 586     } else if (!visible && m_headerWidget->isVisible()) {
 587         disconnect(m_headerWidget, SIGNAL(columnWidthChanged(QByteArray,qreal,qreal)),
 588                    this, SLOT(slotHeaderColumnWidthChanged(QByteArray,qreal,qreal)));
 589         disconnect(m_headerWidget, SIGNAL(columnMoved(QByteArray,int,int)),
 590                    this, SLOT(slotHeaderColumnMoved(QByteArray,int,int)));
 591         disconnect(m_headerWidget, SIGNAL(sortOrderChanged(Qt::SortOrder,Qt::SortOrder)),
 592                    this, SIGNAL(sortOrderChanged(Qt::SortOrder,Qt::SortOrder)));
 593         disconnect(m_headerWidget, SIGNAL(sortRoleChanged(QByteArray,QByteArray)),
 594                    this, SIGNAL(sortRoleChanged(QByteArray,QByteArray)));
 595
 596         m_layouter->setHeaderHeight(0);
 597         m_headerWidget->setVisible(false);
 598     }
 599 }
 600
 601 bool KItemListView::isHeaderVisible() const
 602 {
 603     return m_headerWidget->isVisible();
 604 }
 605
 606 KItemListHeader* KItemListView::header() const
 607 {
 608     return m_header;
 609 }
 610
 611 QPixmap KItemListView::createDragPixmap(const KItemSet& indexes) const
 612 {
 613     QPixmap pixmap;
 614
 615     if (indexes.count() == 1) {
 616         KItemListWidget* item = m_visibleItems.value(indexes.first());
 617         QGraphicsView* graphicsView = scene()->views()[0];
 618         if (item && graphicsView) {
 619             pixmap = item->createDragPixmap(0, graphicsView);
 620         }
 621     } else {
 622         // TODO: Not implemented yet. Probably extend the interface
 623         // from KItemListWidget::createDragPixmap() to return a pixmap
 624         // that can be used for multiple indexes.
 625     }
 626
 627     return pixmap;
 628 }
 629
 630 void KItemListView::editRole(int index, const QByteArray& role)
 631 {
 632     KItemListWidget* widget = m_visibleItems.value(index);
 633     if (!widget || m_editingRole) {
 634         return;
 635     }
 636
 637     m_editingRole = true;
 638     widget->setEditedRole(role);
 639
 640     connect(widget, SIGNAL(roleEditingCanceled(int,QByteArray,QVariant)),
 641             this, SLOT(slotRoleEditingCanceled(int,QByteArray,QVariant)));
 642     connect(widget, SIGNAL(roleEditingFinished(int,QByteArray,QVariant)),
 643             this, SLOT(slotRoleEditingFinished(int,QByteArray,QVariant)));
 644 }
 645
 646 void KItemListView::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget)
 647 {
 648     QGraphicsWidget::paint(painter, option, widget);
 649
 650     if (m_rubberBand->isActive()) {
 651         QRectF rubberBandRect = QRectF(m_rubberBand->startPosition(),
 652                                        m_rubberBand->endPosition()).normalized();
 653
 654         const QPointF topLeft = rubberBandRect.topLeft();
 655         if (scrollOrientation() == Qt::Vertical) {
 656             rubberBandRect.moveTo(topLeft.x(), topLeft.y() - scrollOffset());
 657         } else {
 658             rubberBandRect.moveTo(topLeft.x() - scrollOffset(), topLeft.y());
 659         }
 660
 661         QStyleOptionRubberBand opt;
 662         opt.initFrom(widget);
 663         opt.shape = QRubberBand::Rectangle;
 664         opt.opaque = false;
 665         opt.rect = rubberBandRect.toRect();
 666         style()->drawControl(QStyle::CE_RubberBand, &opt, painter);
 667     }
 668
 669     if (!m_dropIndicator.isEmpty()) {
 670         const QRectF r = m_dropIndicator.toRect();
 671
 672         QColor color = palette().brush(QPalette::Normal, QPalette::Highlight).color();
 673         painter->setPen(color);
 674
 675         // TODO: The following implementation works only for a vertical scroll-orientation
 676         // and assumes a height of the m_draggingInsertIndicator of 1.
 677         Q_ASSERT(r.height() == 1);
 678         painter->drawLine(r.left() + 1, r.top(), r.right() - 1, r.top());
 679
 680         color.setAlpha(128);
 681         painter->setPen(color);
 682         painter->drawRect(r.left(), r.top() - 1, r.width() - 1, 2);
 683     }
 684 }
 685
 686 QVariant KItemListView::itemChange(GraphicsItemChange change, const QVariant &value)
 687 {
 688     if (change == QGraphicsItem::ItemSceneHasChanged && scene()) {
 689         if (!scene()->views().isEmpty()) {
 690             m_styleOption.palette = scene()->views().at(0)->palette();
 691         }
 692     }
 693     return QGraphicsItem::itemChange(change, value);
 694 }
 695
 696 void KItemListView::setItemSize(const QSizeF& size)
 697 {
 698     const QSizeF previousSize = m_itemSize;
 699     if (size == previousSize) {
 700         return;
 701     }
 702
 703     // Skip animations when the number of rows or columns
 704     // are changed in the grid layout. Although the animation
 705     // engine can handle this usecase, it looks obtrusive.
 706     const bool animate = !changesItemGridLayout(m_layouter->size(),
 707                                                 size,
 708                                                 m_layouter->itemMargin());
 709
 710     const bool alternateBackgroundsChanged = (m_visibleRoles.count() > 1) &&
 711                                              (( m_itemSize.isEmpty() && !size.isEmpty()) ||
 712                                               (!m_itemSize.isEmpty() && size.isEmpty()));
 713
 714     m_itemSize = size;
 715
 716     if (alternateBackgroundsChanged) {
 717         // For an empty item size alternate backgrounds are drawn if more than
 718         // one role is shown. Assure that the backgrounds for visible items are
 719         // updated when changing the size in this context.
 720         updateAlternateBackgrounds();
 721     }
 722
 723     if (size.isEmpty()) {
 724         if (m_headerWidget->automaticColumnResizing()) {
 725             updatePreferredColumnWidths();
 726         } else {
 727             // Only apply the changed height and respect the header widths
 728             // set by the user
 729             const qreal currentWidth = m_layouter->itemSize().width();
 730             const QSizeF newSize(currentWidth, size.height());
 731             m_layouter->setItemSize(newSize);
 732         }
 733     } else {
 734         m_layouter->setItemSize(size);
 735     }
 736
 737     m_sizeHintResolver->clearCache();
 738     doLayout(animate ? Animation : NoAnimation);
 739     onItemSizeChanged(size, previousSize);
 740 }
 741
 742 void KItemListView::setStyleOption(const KItemListStyleOption& option)
 743 {
 744     const KItemListStyleOption previousOption = m_styleOption;
 745     m_styleOption = option;
 746
 747     bool animate = true;
 748     const QSizeF margin(option.horizontalMargin, option.verticalMargin);
 749     if (margin != m_layouter->itemMargin()) {
 750         // Skip animations when the number of rows or columns
 751         // are changed in the grid layout. Although the animation
 752         // engine can handle this usecase, it looks obtrusive.
 753         animate = !changesItemGridLayout(m_layouter->size(),
 754                                          m_layouter->itemSize(),
 755                                          margin);
 756         m_layouter->setItemMargin(margin);
 757     }
 758
 759     if (m_grouped) {
 760         updateGroupHeaderHeight();
 761     }
 762
 763     if (animate && previousOption.maxTextSize != option.maxTextSize) {
 764         // Animating a change of the maximum text size just results in expensive
 765         // temporary eliding and clipping operations and does not look good visually.
 766         animate = false;
 767     }
 768
 769     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 770     while (it.hasNext()) {
 771         it.next();
 772         it.value()->setStyleOption(option);
 773     }
 774
 775     m_sizeHintResolver->clearCache();
 776     m_layouter->markAsDirty();
 777     doLayout(animate ? Animation : NoAnimation);
 778
 779     if (m_itemSize.isEmpty()) {
 780         updatePreferredColumnWidths();
 781     }
 782
 783     onStyleOptionChanged(option, previousOption);
 784 }
 785
 786 void KItemListView::setScrollOrientation(Qt::Orientation orientation)
 787 {
 788     const Qt::Orientation previousOrientation = m_layouter->scrollOrientation();
 789     if (orientation == previousOrientation) {
 790         return;
 791     }
 792
 793     m_layouter->setScrollOrientation(orientation);
 794     m_animation->setScrollOrientation(orientation);
 795     m_sizeHintResolver->clearCache();
 796
 797     if (m_grouped) {
 798         QMutableHashIterator<KItemListWidget*, KItemListGroupHeader*> it (m_visibleGroups);
 799         while (it.hasNext()) {
 800             it.next();
 801             it.value()->setScrollOrientation(orientation);
 802         }
 803         updateGroupHeaderHeight();
 804
 805     }
 806
 807     doLayout(NoAnimation);
 808
 809     onScrollOrientationChanged(orientation, previousOrientation);
 810     emit scrollOrientationChanged(orientation, previousOrientation);
 811 }
 812
 813 Qt::Orientation KItemListView::scrollOrientation() const
 814 {
 815     return m_layouter->scrollOrientation();
 816 }
 817
 818 KItemListWidgetCreatorBase* KItemListView::defaultWidgetCreator() const
 819 {
 820     return 0;
 821 }
 822
 823 KItemListGroupHeaderCreatorBase* KItemListView::defaultGroupHeaderCreator() const
 824 {
 825     return 0;
 826 }
 827
 828 void KItemListView::initializeItemListWidget(KItemListWidget* item)
 829 {
 830     Q_UNUSED(item);
 831 }
 832
 833 bool KItemListView::itemSizeHintUpdateRequired(const QSet<QByteArray>& changedRoles) const
 834 {
 835     Q_UNUSED(changedRoles);
 836     return true;
 837 }
 838
 839 void KItemListView::onControllerChanged(KItemListController* current, KItemListController* previous)
 840 {
 841     Q_UNUSED(current);
 842     Q_UNUSED(previous);
 843 }
 844
 845 void KItemListView::onModelChanged(KItemModelBase* current, KItemModelBase* previous)
 846 {
 847     Q_UNUSED(current);
 848     Q_UNUSED(previous);
 849 }
 850
 851 void KItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
 852 {
 853     Q_UNUSED(current);
 854     Q_UNUSED(previous);
 855 }
 856
 857 void KItemListView::onItemSizeChanged(const QSizeF& current, const QSizeF& previous)
 858 {
 859     Q_UNUSED(current);
 860     Q_UNUSED(previous);
 861 }
 862
 863 void KItemListView::onScrollOffsetChanged(qreal current, qreal previous)
 864 {
 865     Q_UNUSED(current);
 866     Q_UNUSED(previous);
 867 }
 868
 869 void KItemListView::onVisibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous)
 870 {
 871     Q_UNUSED(current);
 872     Q_UNUSED(previous);
 873 }
 874
 875 void KItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
 876 {
 877     Q_UNUSED(current);
 878     Q_UNUSED(previous);
 879 }
 880
 881 void KItemListView::onSupportsItemExpandingChanged(bool supportsExpanding)
 882 {
 883     Q_UNUSED(supportsExpanding);
 884 }
 885
 886 void KItemListView::onTransactionBegin()
 887 {
 888 }
 889
 890 void KItemListView::onTransactionEnd()
 891 {
 892 }
 893
 894 bool KItemListView::event(QEvent* event)
 895 {
 896     // Forward all events to the controller and handle them there
 897     if (!m_editingRole && m_controller && m_controller->processEvent(event, transform())) {
 898         event->accept();
 899         return true;
 900     }
 901     return QGraphicsWidget::event(event);
 902 }
 903
 904 void KItemListView::mousePressEvent(QGraphicsSceneMouseEvent* event)
 905 {
 906     m_mousePos = transform().map(event->pos());
 907     event->accept();
 908 }
 909
 910 void KItemListView::mouseMoveEvent(QGraphicsSceneMouseEvent* event)
 911 {
 912     QGraphicsWidget::mouseMoveEvent(event);
 913
 914     m_mousePos = transform().map(event->pos());
 915     if (m_autoScrollTimer && !m_autoScrollTimer->isActive()) {
 916         m_autoScrollTimer->start(InitialAutoScrollDelay);
 917     }
 918 }
 919
 920 void KItemListView::dragEnterEvent(QGraphicsSceneDragDropEvent* event)
 921 {
 922     event->setAccepted(true);
 923     setAutoScroll(true);
 924 }
 925
 926 void KItemListView::dragMoveEvent(QGraphicsSceneDragDropEvent *event)
 927 {
 928     QGraphicsWidget::dragMoveEvent(event);
 929
 930     m_mousePos = transform().map(event->pos());
 931     if (m_autoScrollTimer && !m_autoScrollTimer->isActive()) {
 932         m_autoScrollTimer->start(InitialAutoScrollDelay);
 933     }
 934 }
 935
 936 void KItemListView::dragLeaveEvent(QGraphicsSceneDragDropEvent *event)
 937 {
 938     QGraphicsWidget::dragLeaveEvent(event);
 939     setAutoScroll(false);
 940 }
 941
 942 void KItemListView::dropEvent(QGraphicsSceneDragDropEvent* event)
 943 {
 944     QGraphicsWidget::dropEvent(event);
 945     setAutoScroll(false);
 946 }
 947
 948 QList<KItemListWidget*> KItemListView::visibleItemListWidgets() const
 949 {
 950     return m_visibleItems.values();
 951 }
 952
 953 void KItemListView::slotItemsInserted(const KItemRangeList& itemRanges)
 954 {
 955     if (m_itemSize.isEmpty()) {
 956         updatePreferredColumnWidths(itemRanges);
 957     }
 958
 959     const bool hasMultipleRanges = (itemRanges.count() > 1);
 960     if (hasMultipleRanges) {
 961         beginTransaction();
 962     }
 963
 964     m_layouter->markAsDirty();
 965
 966     m_sizeHintResolver->itemsInserted(itemRanges);
 967
 968     int previouslyInsertedCount = 0;
 969     foreach (const KItemRange& range, itemRanges) {
 970         // range.index is related to the model before anything has been inserted.
 971         // As in each loop the current item-range gets inserted the index must
 972         // be increased by the already previously inserted items.
 973         const int index = range.index + previouslyInsertedCount;
 974         const int count = range.count;
 975         if (index < 0 || count <= 0) {
 976             kWarning() << "Invalid item range (index:" << index << ", count:" << count << ")";
 977             continue;
 978         }
 979         previouslyInsertedCount += count;
 980
 981         // Determine which visible items must be moved
 982         QList<int> itemsToMove;
 983         QHashIterator<int, KItemListWidget*> it(m_visibleItems);
 984         while (it.hasNext()) {
 985             it.next();
 986             const int visibleItemIndex = it.key();
 987             if (visibleItemIndex >= index) {
 988                 itemsToMove.append(visibleItemIndex);
 989             }
 990         }
 991
 992         // Update the indexes of all KItemListWidget instances that are located
 993         // after the inserted items. It is important to adjust the indexes in the order
 994         // from the highest index to the lowest index to prevent overlaps when setting the new index.
 995         qSort(itemsToMove);
 996         for (int i = itemsToMove.count() - 1; i >= 0; --i) {
 997             KItemListWidget* widget = m_visibleItems.value(itemsToMove[i]);
 998             Q_ASSERT(widget);
 999             const int newIndex = widget->index() + count;
1000             if (hasMultipleRanges) {
1001                 setWidgetIndex(widget, newIndex);
1002             } else {
1003                 // Try to animate the moving of the item
1004                 moveWidgetToIndex(widget, newIndex);
1005             }
1006         }
1007
1008         if (m_model->count() == count && m_activeTransactions == 0) {
1009             // Check whether a scrollbar is required to show the inserted items. In this case
1010             // the size of the layouter will be decreased before calling doLayout(): This prevents
1011             // an unnecessary temporary animation due to the geometry change of the inserted scrollbar.
1012             const bool verticalScrollOrientation = (scrollOrientation() == Qt::Vertical);
1013             const bool decreaseLayouterSize = ( verticalScrollOrientation && maximumScrollOffset() > size().height()) ||
1014                                               (!verticalScrollOrientation && maximumScrollOffset() > size().width());
1015             if (decreaseLayouterSize) {
1016                 const int scrollBarExtent = style()->pixelMetric(QStyle::PM_ScrollBarExtent);
1017                 QSizeF layouterSize = m_layouter->size();
1018                 if (verticalScrollOrientation) {
1019                     layouterSize.rwidth() -= scrollBarExtent;
1020                 } else {
1021                     layouterSize.rheight() -= scrollBarExtent;
1022                 }
1023                 m_layouter->setSize(layouterSize);
1024             }
1025         }
1026
1027         if (!hasMultipleRanges) {
1028             doLayout(animateChangedItemCount(count) ? Animation : NoAnimation, index, count);
1029             updateSiblingsInformation();
1030         }
1031     }
1032
1033     if (m_controller) {
1034         m_controller->selectionManager()->itemsInserted(itemRanges);
1035     }
1036
1037     if (hasMultipleRanges) {
1038         m_endTransactionAnimationHint = NoAnimation;
1039         endTransaction();
1040
1041         updateSiblingsInformation();
1042     }
1043
1044     if (m_grouped && (hasMultipleRanges || itemRanges.first().count < m_model->count())) {
1045         // In case if items of the same group have been inserted before an item that
1046         // currently represents the first item of the group, the group header of
1047         // this item must be removed.
1048         updateVisibleGroupHeaders();
1049     }
1050
1051     if (useAlternateBackgrounds()) {
1052         updateAlternateBackgrounds();
1053     }
1054 }
1055
1056 void KItemListView::slotItemsRemoved(const KItemRangeList& itemRanges)
1057 {
1058     if (m_itemSize.isEmpty()) {
1059         // Don't pass the item-range: The preferred column-widths of
1060         // all items must be adjusted when removing items.
1061         updatePreferredColumnWidths();
1062     }
1063
1064     const bool hasMultipleRanges = (itemRanges.count() > 1);
1065     if (hasMultipleRanges) {
1066         beginTransaction();
1067     }
1068
1069     m_layouter->markAsDirty();
1070
1071     m_sizeHintResolver->itemsRemoved(itemRanges);
1072
1073     for (int i = itemRanges.count() - 1; i >= 0; --i) {
1074         const KItemRange& range = itemRanges[i];
1075         const int index = range.index;
1076         const int count = range.count;
1077         if (index < 0 || count <= 0) {
1078             kWarning() << "Invalid item range (index:" << index << ", count:" << count << ")";
1079             continue;
1080         }
1081
1082         const int firstRemovedIndex = index;
1083         const int lastRemovedIndex = index + count - 1;
1084
1085         // Remeber which items have to be moved because they are behind the removed range.
1086         QVector<int> itemsToMove;
1087
1088         // Remove all KItemListWidget instances that got deleted
1089         foreach (KItemListWidget* widget, m_visibleItems) {
1090             const int i = widget->index();
1091             if (i < firstRemovedIndex) {
1092                 continue;
1093             } else if (i > lastRemovedIndex) {
1094                 itemsToMove.append(i);
1095                 continue;
1096             }
1097
1098             m_animation->stop(widget);
1099             // Stopping the animation might lead to recycling the widget if
1100             // it is invisible (see slotAnimationFinished()).
1101             // Check again whether it is still visible:
1102             if (!m_visibleItems.contains(i)) {
1103                 continue;
1104             }
1105
1106             if (m_model->count() == 0 || hasMultipleRanges || !animateChangedItemCount(count)) {
1107                 // Remove the widget without animation
1108                 recycleWidget(widget);
1109             } else {
1110                 // Animate the removing of the items. Special case: When removing an item there
1111                 // is no valid model index available anymore. For the
1112                 // remove-animation the item gets removed from m_visibleItems but the widget
1113                 // will stay alive until the animation has been finished and will
1114                 // be recycled (deleted) in KItemListView::slotAnimationFinished().
1115                 m_visibleItems.remove(i);
1116                 widget->setIndex(-1);
1117                 m_animation->start(widget, KItemListViewAnimation::DeleteAnimation);
1118             }
1119         }
1120
1121         // Update the indexes of all KItemListWidget instances that are located
1122         // after the deleted items. It is important to update them in ascending
1123         // order to prevent overlaps when setting the new index.
1124         std::sort(itemsToMove.begin(), itemsToMove.end());
1125         foreach (int i, itemsToMove) {
1126             KItemListWidget* widget = m_visibleItems.value(i);
1127             Q_ASSERT(widget);
1128             const int newIndex = i - count;
1129             if (hasMultipleRanges) {
1130                 setWidgetIndex(widget, newIndex);
1131             } else {
1132                 // Try to animate the moving of the item
1133                 moveWidgetToIndex(widget, newIndex);
1134             }
1135         }
1136
1137         if (!hasMultipleRanges) {
1138             // The decrease-layout-size optimization in KItemListView::slotItemsInserted()
1139             // assumes an updated geometry. If items are removed during an active transaction,
1140             // the transaction will be temporary deactivated so that doLayout() triggers a
1141             // geometry update if necessary.
1142             const int activeTransactions = m_activeTransactions;
1143             m_activeTransactions = 0;
1144             doLayout(animateChangedItemCount(count) ? Animation : NoAnimation, index, -count);
1145             m_activeTransactions = activeTransactions;
1146             updateSiblingsInformation();
1147         }
1148     }
1149
1150     if (m_controller) {
1151         m_controller->selectionManager()->itemsRemoved(itemRanges);
1152     }
1153
1154     if (hasMultipleRanges) {
1155         m_endTransactionAnimationHint = NoAnimation;
1156         endTransaction();
1157         updateSiblingsInformation();
1158     }
1159
1160     if (m_grouped && (hasMultipleRanges || m_model->count() > 0)) {
1161         // In case if the first item of a group has been removed, the group header
1162         // must be applied to the next visible item.
1163         updateVisibleGroupHeaders();
1164     }
1165
1166     if (useAlternateBackgrounds()) {
1167         updateAlternateBackgrounds();
1168     }
1169 }
1170
1171 void KItemListView::slotItemsMoved(const KItemRange& itemRange, const QList<int>& movedToIndexes)
1172 {
1173     m_sizeHintResolver->itemsMoved(itemRange, movedToIndexes);
1174     m_layouter->markAsDirty();
1175
1176     if (m_controller) {
1177         m_controller->selectionManager()->itemsMoved(itemRange, movedToIndexes);
1178     }
1179
1180     const int firstVisibleMovedIndex = qMax(firstVisibleIndex(), itemRange.index);
1181     const int lastVisibleMovedIndex = qMin(lastVisibleIndex(), itemRange.index + itemRange.count - 1);
1182
1183     for (int index = firstVisibleMovedIndex; index <= lastVisibleMovedIndex; ++index) {
1184         KItemListWidget* widget = m_visibleItems.value(index);
1185         if (widget) {
1186             updateWidgetProperties(widget, index);
1187             initializeItemListWidget(widget);
1188         }
1189     }
1190
1191     doLayout(NoAnimation);
1192     updateSiblingsInformation();
1193 }
1194
1195 void KItemListView::slotItemsChanged(const KItemRangeList& itemRanges,
1196                                      const QSet<QByteArray>& roles)
1197 {
1198     const bool updateSizeHints = itemSizeHintUpdateRequired(roles);
1199     if (updateSizeHints && m_itemSize.isEmpty()) {
1200         updatePreferredColumnWidths(itemRanges);
1201     }
1202
1203     foreach (const KItemRange& itemRange, itemRanges) {
1204         const int index = itemRange.index;
1205         const int count = itemRange.count;
1206
1207         if (updateSizeHints) {
1208             m_sizeHintResolver->itemsChanged(index, count, roles);
1209             m_layouter->markAsDirty();
1210
1211             if (!m_layoutTimer->isActive()) {
1212                 m_layoutTimer->start();
1213             }
1214         }
1215
1216         // Apply the changed roles to the visible item-widgets
1217         const int lastIndex = index + count - 1;
1218         for (int i = index; i <= lastIndex; ++i) {
1219             KItemListWidget* widget = m_visibleItems.value(i);
1220             if (widget) {
1221                 widget->setData(m_model->data(i), roles);
1222             }
1223         }
1224
1225         if (m_grouped && roles.contains(m_model->sortRole())) {
1226             // The sort-role has been changed which might result
1227             // in modified group headers
1228             updateVisibleGroupHeaders();
1229             doLayout(NoAnimation);
1230         }
1231     }
1232     QAccessible::updateAccessibility(this, 0, QAccessible::TableModelChanged);
1233 }
1234
1235 void KItemListView::slotGroupsChanged()
1236 {
1237     updateVisibleGroupHeaders();
1238     doLayout(NoAnimation);
1239     updateSiblingsInformation();
1240 }
1241
1242 void KItemListView::slotGroupedSortingChanged(bool current)
1243 {
1244     m_grouped = current;
1245     m_layouter->markAsDirty();
1246
1247     if (m_grouped) {
1248         updateGroupHeaderHeight();
1249     } else {
1250         // Clear all visible headers. Note that the QHashIterator takes a copy of
1251         // m_visibleGroups. Therefore, it remains valid even if items are removed
1252         // from m_visibleGroups in recycleGroupHeaderForWidget().
1253         QHashIterator<KItemListWidget*, KItemListGroupHeader*> it(m_visibleGroups);
1254         while (it.hasNext()) {
1255             it.next();
1256             recycleGroupHeaderForWidget(it.key());
1257         }
1258         Q_ASSERT(m_visibleGroups.isEmpty());
1259     }
1260
1261     if (useAlternateBackgrounds()) {
1262         // Changing the group mode requires to update the alternate backgrounds
1263         // as with the enabled group mode the altering is done on base of the first
1264         // group item.
1265         updateAlternateBackgrounds();
1266     }
1267     updateSiblingsInformation();
1268     doLayout(NoAnimation);
1269 }
1270
1271 void KItemListView::slotSortOrderChanged(Qt::SortOrder current, Qt::SortOrder previous)
1272 {
1273     Q_UNUSED(current);
1274     Q_UNUSED(previous);
1275     if (m_grouped) {
1276         updateVisibleGroupHeaders();
1277         doLayout(NoAnimation);
1278     }
1279 }
1280
1281 void KItemListView::slotSortRoleChanged(const QByteArray& current, const QByteArray& previous)
1282 {
1283     Q_UNUSED(current);
1284     Q_UNUSED(previous);
1285     if (m_grouped) {
1286         updateVisibleGroupHeaders();
1287         doLayout(NoAnimation);
1288     }
1289 }
1290
1291 void KItemListView::slotCurrentChanged(int current, int previous)
1292 {
1293     Q_UNUSED(previous);
1294
1295     KItemListWidget* previousWidget = m_visibleItems.value(previous, 0);
1296     if (previousWidget) {
1297         previousWidget->setCurrent(false);
1298     }
1299
1300     KItemListWidget* currentWidget = m_visibleItems.value(current, 0);
1301     if (currentWidget) {
1302         currentWidget->setCurrent(true);
1303     }
1304     QAccessible::updateAccessibility(this, current+1, QAccessible::Focus);
1305 }
1306
1307 void KItemListView::slotSelectionChanged(const KItemSet& current, const KItemSet& previous)
1308 {
1309     Q_UNUSED(previous);
1310
1311     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
1312     while (it.hasNext()) {
1313         it.next();
1314         const int index = it.key();
1315         KItemListWidget* widget = it.value();
1316         widget->setSelected(current.contains(index));
1317     }
1318 }
1319
1320 void KItemListView::slotAnimationFinished(QGraphicsWidget* widget,
1321                                           KItemListViewAnimation::AnimationType type)
1322 {
1323     KItemListWidget* itemListWidget = qobject_cast<KItemListWidget*>(widget);
1324     Q_ASSERT(itemListWidget);
1325
1326     switch (type) {
1327     case KItemListViewAnimation::DeleteAnimation: {
1328         // As we recycle the widget in this case it is important to assure that no
1329         // other animation has been started. This is a convention in KItemListView and
1330         // not a requirement defined by KItemListViewAnimation.
1331         Q_ASSERT(!m_animation->isStarted(itemListWidget));
1332
1333         // All KItemListWidgets that are animated by the DeleteAnimation are not maintained
1334         // by m_visibleWidgets and must be deleted manually after the animation has
1335         // been finished.
1336         recycleGroupHeaderForWidget(itemListWidget);
1337         widgetCreator()->recycle(itemListWidget);
1338         break;
1339     }
1340
1341     case KItemListViewAnimation::CreateAnimation:
1342     case KItemListViewAnimation::MovingAnimation:
1343     case KItemListViewAnimation::ResizeAnimation: {
1344         const int index = itemListWidget->index();
1345         const bool invisible = (index < m_layouter->firstVisibleIndex()) ||
1346                                (index > m_layouter->lastVisibleIndex());
1347         if (invisible && !m_animation->isStarted(itemListWidget)) {
1348             recycleWidget(itemListWidget);
1349         }
1350         break;
1351     }
1352
1353     default: break;
1354     }
1355 }
1356
1357 void KItemListView::slotLayoutTimerFinished()
1358 {
1359     m_layouter->setSize(geometry().size());
1360     doLayout(Animation);
1361 }
1362
1363 void KItemListView::slotRubberBandPosChanged()
1364 {
1365     update();
1366 }
1367
1368 void KItemListView::slotRubberBandActivationChanged(bool active)
1369 {
1370     if (active) {
1371         connect(m_rubberBand, SIGNAL(startPositionChanged(QPointF,QPointF)), this, SLOT(slotRubberBandPosChanged()));
1372         connect(m_rubberBand, SIGNAL(endPositionChanged(QPointF,QPointF)), this, SLOT(slotRubberBandPosChanged()));
1373         m_skipAutoScrollForRubberBand = true;
1374     } else {
1375         disconnect(m_rubberBand, SIGNAL(startPositionChanged(QPointF,QPointF)), this, SLOT(slotRubberBandPosChanged()));
1376         disconnect(m_rubberBand, SIGNAL(endPositionChanged(QPointF,QPointF)), this, SLOT(slotRubberBandPosChanged()));
1377         m_skipAutoScrollForRubberBand = false;
1378     }
1379
1380     update();
1381 }
1382
1383 void KItemListView::slotHeaderColumnWidthChanged(const QByteArray& role,
1384                                                  qreal currentWidth,
1385                                                  qreal previousWidth)
1386 {
1387     Q_UNUSED(role);
1388     Q_UNUSED(currentWidth);
1389     Q_UNUSED(previousWidth);
1390
1391     m_headerWidget->setAutomaticColumnResizing(false);
1392     applyColumnWidthsFromHeader();
1393     doLayout(NoAnimation);
1394 }
1395
1396 void KItemListView::slotHeaderColumnMoved(const QByteArray& role,
1397                                           int currentIndex,
1398                                           int previousIndex)
1399 {
1400     Q_ASSERT(m_visibleRoles[previousIndex] == role);
1401
1402     const QList<QByteArray> previous = m_visibleRoles;
1403
1404     QList<QByteArray> current = m_visibleRoles;
1405     current.removeAt(previousIndex);
1406     current.insert(currentIndex, role);
1407
1408     setVisibleRoles(current);
1409
1410     emit visibleRolesChanged(current, previous);
1411 }
1412
1413 void KItemListView::triggerAutoScrolling()
1414 {
1415     if (!m_autoScrollTimer) {
1416         return;
1417     }
1418
1419     int pos = 0;
1420     int visibleSize = 0;
1421     if (scrollOrientation() == Qt::Vertical) {
1422         pos = m_mousePos.y();
1423         visibleSize = size().height();
1424     } else {
1425         pos = m_mousePos.x();
1426         visibleSize = size().width();
1427     }
1428
1429     if (m_autoScrollTimer->interval() == InitialAutoScrollDelay) {
1430         m_autoScrollIncrement = 0;
1431     }
1432
1433     m_autoScrollIncrement = calculateAutoScrollingIncrement(pos, visibleSize, m_autoScrollIncrement);
1434     if (m_autoScrollIncrement == 0) {
1435         // The mouse position is not above an autoscroll margin (the autoscroll timer
1436         // will be restarted in mouseMoveEvent())
1437         m_autoScrollTimer->stop();
1438         return;
1439     }
1440
1441     if (m_rubberBand->isActive() && m_skipAutoScrollForRubberBand) {
1442         // If a rubberband selection is ongoing the autoscrolling may only get triggered
1443         // if the direction of the rubberband is similar to the autoscroll direction. This
1444         // prevents that starting to create a rubberband within the autoscroll margins starts
1445         // an autoscrolling.
1446
1447         const qreal minDiff = 4; // Ignore any autoscrolling if the rubberband is very small
1448         const qreal diff = (scrollOrientation() == Qt::Vertical)
1449                            ? m_rubberBand->endPosition().y() - m_rubberBand->startPosition().y()
1450                            : m_rubberBand->endPosition().x() - m_rubberBand->startPosition().x();
1451         if (qAbs(diff) < minDiff || (m_autoScrollIncrement < 0 && diff > 0) || (m_autoScrollIncrement > 0 && diff < 0)) {
1452             // The rubberband direction is different from the scroll direction (e.g. the rubberband has
1453             // been moved up although the autoscroll direction might be down)
1454             m_autoScrollTimer->stop();
1455             return;
1456         }
1457     }
1458
1459     // As soon as the autoscrolling has been triggered at least once despite having an active rubberband,
1460     // the autoscrolling may not get skipped anymore until a new rubberband is created
1461     m_skipAutoScrollForRubberBand = false;
1462
1463     const qreal maxVisibleOffset = qMax(qreal(0), maximumScrollOffset() - visibleSize);
1464     const qreal newScrollOffset = qMin(scrollOffset() + m_autoScrollIncrement, maxVisibleOffset);
1465     setScrollOffset(newScrollOffset);
1466
1467     // Trigger the autoscroll timer which will periodically call
1468     // triggerAutoScrolling()
1469     m_autoScrollTimer->start(RepeatingAutoScrollDelay);
1470 }
1471
1472 void KItemListView::slotGeometryOfGroupHeaderParentChanged()
1473 {
1474     KItemListWidget* widget = qobject_cast<KItemListWidget*>(sender());
1475     Q_ASSERT(widget);
1476     KItemListGroupHeader* groupHeader = m_visibleGroups.value(widget);
1477     Q_ASSERT(groupHeader);
1478     updateGroupHeaderLayout(widget);
1479 }
1480
1481 void KItemListView::slotRoleEditingCanceled(int index, const QByteArray& role, const QVariant& value)
1482 {
1483     disconnectRoleEditingSignals(index);
1484
1485     emit roleEditingCanceled(index, role, value);
1486     m_editingRole = false;
1487 }
1488
1489 void KItemListView::slotRoleEditingFinished(int index, const QByteArray& role, const QVariant& value)
1490 {
1491     disconnectRoleEditingSignals(index);
1492
1493     emit roleEditingFinished(index, role, value);
1494     m_editingRole = false;
1495 }
1496
1497 void KItemListView::setController(KItemListController* controller)
1498 {
1499     if (m_controller != controller) {
1500         KItemListController* previous = m_controller;
1501         if (previous) {
1502             KItemListSelectionManager* selectionManager = previous->selectionManager();
1503             disconnect(selectionManager, SIGNAL(currentChanged(int,int)), this, SLOT(slotCurrentChanged(int,int)));
1504             disconnect(selectionManager, SIGNAL(selectionChanged(KItemSet,KItemSet)), this, SLOT(slotSelectionChanged(KItemSet,KItemSet)));
1505         }
1506
1507         m_controller = controller;
1508
1509         if (controller) {
1510             KItemListSelectionManager* selectionManager = controller->selectionManager();
1511             connect(selectionManager, SIGNAL(currentChanged(int,int)), this, SLOT(slotCurrentChanged(int,int)));
1512             connect(selectionManager, SIGNAL(selectionChanged(KItemSet,KItemSet)), this, SLOT(slotSelectionChanged(KItemSet,KItemSet)));
1513         }
1514
1515         onControllerChanged(controller, previous);
1516     }
1517 }
1518
1519 void KItemListView::setModel(KItemModelBase* model)
1520 {
1521     if (m_model == model) {
1522         return;
1523     }
1524
1525     KItemModelBase* previous = m_model;
1526
1527     if (m_model) {
1528         disconnect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
1529                    this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
1530         disconnect(m_model, SIGNAL(itemsInserted(KItemRangeList)),
1531                    this,    SLOT(slotItemsInserted(KItemRangeList)));
1532         disconnect(m_model, SIGNAL(itemsRemoved(KItemRangeList)),
1533                    this,    SLOT(slotItemsRemoved(KItemRangeList)));
1534         disconnect(m_model, SIGNAL(itemsMoved(KItemRange,QList<int>)),
1535                    this,    SLOT(slotItemsMoved(KItemRange,QList<int>)));
1536         disconnect(m_model, SIGNAL(groupsChanged()),
1537                    this,    SLOT(slotGroupsChanged()));
1538         disconnect(m_model, SIGNAL(groupedSortingChanged(bool)),
1539                    this,    SLOT(slotGroupedSortingChanged(bool)));
1540         disconnect(m_model, SIGNAL(sortOrderChanged(Qt::SortOrder,Qt::SortOrder)),
1541                    this,    SLOT(slotSortOrderChanged(Qt::SortOrder,Qt::SortOrder)));
1542         disconnect(m_model, SIGNAL(sortRoleChanged(QByteArray,QByteArray)),
1543                    this,    SLOT(slotSortRoleChanged(QByteArray,QByteArray)));
1544
1545         m_sizeHintResolver->itemsRemoved(KItemRangeList() << KItemRange(0, m_model->count()));
1546     }
1547
1548     m_model = model;
1549     m_layouter->setModel(model);
1550     m_grouped = model->groupedSorting();
1551
1552     if (m_model) {
1553         connect(m_model, SIGNAL(itemsChanged(KItemRangeList,QSet<QByteArray>)),
1554                 this,    SLOT(slotItemsChanged(KItemRangeList,QSet<QByteArray>)));
1555         connect(m_model, SIGNAL(itemsInserted(KItemRangeList)),
1556                 this,    SLOT(slotItemsInserted(KItemRangeList)));
1557         connect(m_model, SIGNAL(itemsRemoved(KItemRangeList)),
1558                 this,    SLOT(slotItemsRemoved(KItemRangeList)));
1559         connect(m_model, SIGNAL(itemsMoved(KItemRange,QList<int>)),
1560                 this,    SLOT(slotItemsMoved(KItemRange,QList<int>)));
1561         connect(m_model, SIGNAL(groupsChanged()),
1562                 this,    SLOT(slotGroupsChanged()));
1563         connect(m_model, SIGNAL(groupedSortingChanged(bool)),
1564                 this,    SLOT(slotGroupedSortingChanged(bool)));
1565         connect(m_model, SIGNAL(sortOrderChanged(Qt::SortOrder,Qt::SortOrder)),
1566                 this,    SLOT(slotSortOrderChanged(Qt::SortOrder,Qt::SortOrder)));
1567         connect(m_model, SIGNAL(sortRoleChanged(QByteArray,QByteArray)),
1568                 this,    SLOT(slotSortRoleChanged(QByteArray,QByteArray)));
1569
1570         const int itemCount = m_model->count();
1571         if (itemCount > 0) {
1572             slotItemsInserted(KItemRangeList() << KItemRange(0, itemCount));
1573         }
1574     }
1575
1576     onModelChanged(model, previous);
1577 }
1578
1579 KItemListRubberBand* KItemListView::rubberBand() const
1580 {
1581     return m_rubberBand;
1582 }
1583
1584 void KItemListView::doLayout(LayoutAnimationHint hint, int changedIndex, int changedCount)
1585 {
1586     if (m_layoutTimer->isActive()) {
1587         m_layoutTimer->stop();
1588     }
1589
1590     if (m_activeTransactions > 0) {
1591         if (hint == NoAnimation) {
1592             // As soon as at least one property change should be done without animation,
1593             // the whole transaction will be marked as not animated.
1594             m_endTransactionAnimationHint = NoAnimation;
1595         }
1596         return;
1597     }
1598
1599     if (!m_model || m_model->count() < 0) {
1600         return;
1601     }
1602
1603     int firstVisibleIndex = m_layouter->firstVisibleIndex();
1604     if (firstVisibleIndex < 0) {
1605         emitOffsetChanges();
1606         return;
1607     }
1608
1609     // Do a sanity check of the scroll-offset property: When properties of the itemlist-view have been changed
1610     // it might be possible that the maximum offset got changed too. Assure that the full visible range
1611     // is still shown if the maximum offset got decreased.
1612     const qreal visibleOffsetRange = (scrollOrientation() == Qt::Horizontal) ? size().width() : size().height();
1613     const qreal maxOffsetToShowFullRange = maximumScrollOffset() - visibleOffsetRange;
1614     if (scrollOffset() > maxOffsetToShowFullRange) {
1615         m_layouter->setScrollOffset(qMax(qreal(0), maxOffsetToShowFullRange));
1616         firstVisibleIndex = m_layouter->firstVisibleIndex();
1617     }
1618
1619     const int lastVisibleIndex = m_layouter->lastVisibleIndex();
1620
1621     int firstSibblingIndex = -1;
1622     int lastSibblingIndex = -1;
1623     const bool supportsExpanding = supportsItemExpanding();
1624
1625     QList<int> reusableItems = recycleInvisibleItems(firstVisibleIndex, lastVisibleIndex, hint);
1626
1627     // Assure that for each visible item a KItemListWidget is available. KItemListWidget
1628     // instances from invisible items are reused. If no reusable items are
1629     // found then new KItemListWidget instances get created.
1630     const bool animate = (hint == Animation);
1631     for (int i = firstVisibleIndex; i <= lastVisibleIndex; ++i) {
1632         bool applyNewPos = true;
1633         bool wasHidden = false;
1634
1635         const QRectF itemBounds = m_layouter->itemRect(i);
1636         const QPointF newPos = itemBounds.topLeft();
1637         KItemListWidget* widget = m_visibleItems.value(i);
1638         if (!widget) {
1639             wasHidden = true;
1640             if (!reusableItems.isEmpty()) {
1641                 // Reuse a KItemListWidget instance from an invisible item
1642                 const int oldIndex = reusableItems.takeLast();
1643                 widget = m_visibleItems.value(oldIndex);
1644                 setWidgetIndex(widget, i);
1645                 updateWidgetProperties(widget, i);
1646                 initializeItemListWidget(widget);
1647             } else {
1648                 // No reusable KItemListWidget instance is available, create a new one
1649                 widget = createWidget(i);
1650             }
1651             widget->resize(itemBounds.size());
1652
1653             if (animate && changedCount < 0) {
1654                 // Items have been deleted.
1655                 if (i >= changedIndex) {
1656                     // The item is located behind the removed range. Move the
1657                     // created item to the imaginary old position outside the
1658                     // view. It will get animated to the new position later.
1659                     const int previousIndex = i - changedCount;
1660                     const QRectF itemRect = m_layouter->itemRect(previousIndex);
1661                     if (itemRect.isEmpty()) {
1662                         const QPointF invisibleOldPos = (scrollOrientation() == Qt::Vertical)
1663                                                         ? QPointF(0, size().height()) : QPointF(size().width(), 0);
1664                         widget->setPos(invisibleOldPos);
1665                     } else {
1666                         widget->setPos(itemRect.topLeft());
1667                     }
1668                     applyNewPos = false;
1669                 }
1670             }
1671
1672             if (supportsExpanding && changedCount == 0) {
1673                 if (firstSibblingIndex < 0) {
1674                     firstSibblingIndex = i;
1675                 }
1676                 lastSibblingIndex = i;
1677             }
1678         }
1679
1680         if (animate) {
1681             if (m_animation->isStarted(widget, KItemListViewAnimation::MovingAnimation)) {
1682                 m_animation->start(widget,  KItemListViewAnimation::MovingAnimation, newPos);
1683                 applyNewPos = false;
1684             }
1685
1686             const bool itemsRemoved = (changedCount < 0);
1687             const bool itemsInserted = (changedCount > 0);
1688             if (itemsRemoved && (i >= changedIndex)) {
1689                 // The item is located after the removed items. Animate the moving of the position.
1690                 applyNewPos = !moveWidget(widget, newPos);
1691             } else if (itemsInserted && i >= changedIndex) {
1692                 // The item is located after the first inserted item
1693                 if (i <= changedIndex + changedCount - 1) {
1694                     // The item is an inserted item. Animate the appearing of the item.
1695                     // For performance reasons no animation is done when changedCount is equal
1696                     // to all available items.
1697                     if (changedCount < m_model->count()) {
1698                         m_animation->start(widget, KItemListViewAnimation::CreateAnimation);
1699                     }
1700                 } else if (!m_animation->isStarted(widget, KItemListViewAnimation::CreateAnimation)) {
1701                     // The item was already there before, so animate the moving of the position.
1702                     // No moving animation is done if the item is animated by a create animation: This
1703                     // prevents a "move animation mess" when inserting several ranges in parallel.
1704                     applyNewPos = !moveWidget(widget, newPos);
1705                 }
1706             } else if (!itemsRemoved && !itemsInserted && !wasHidden) {
1707                 // The size of the view might have been changed. Animate the moving of the position.
1708                 applyNewPos = !moveWidget(widget, newPos);
1709             }
1710         } else {
1711             m_animation->stop(widget);
1712         }
1713
1714         if (applyNewPos) {
1715             widget->setPos(newPos);
1716         }
1717
1718         Q_ASSERT(widget->index() == i);
1719         widget->setVisible(true);
1720
1721         if (widget->size() != itemBounds.size()) {
1722             // Resize the widget for the item to the changed size.
1723             if (animate) {
1724                 // If a dynamic item size is used then no animation is done in the direction
1725                 // of the dynamic size.
1726                 if (m_itemSize.width() <= 0) {
1727                     // The width is dynamic, apply the new width without animation.
1728                     widget->resize(itemBounds.width(), widget->size().height());
1729                 } else if (m_itemSize.height() <= 0) {
1730                     // The height is dynamic, apply the new height without animation.
1731                     widget->resize(widget->size().width(), itemBounds.height());
1732                 }
1733                 m_animation->start(widget, KItemListViewAnimation::ResizeAnimation, itemBounds.size());
1734             } else {
1735                 widget->resize(itemBounds.size());
1736             }
1737         }
1738
1739         // Updating the cell-information must be done as last step: The decision whether the
1740         // moving-animation should be started at all is based on the previous cell-information.
1741         const Cell cell(m_layouter->itemColumn(i), m_layouter->itemRow(i));
1742         m_visibleCells.insert(i, cell);
1743     }
1744
1745     // Delete invisible KItemListWidget instances that have not been reused
1746     foreach (int index, reusableItems) {
1747         recycleWidget(m_visibleItems.value(index));
1748     }
1749
1750     if (supportsExpanding && firstSibblingIndex >= 0) {
1751         Q_ASSERT(lastSibblingIndex >= 0);
1752         updateSiblingsInformation(firstSibblingIndex, lastSibblingIndex);
1753     }
1754
1755     if (m_grouped) {
1756         // Update the layout of all visible group headers
1757         QHashIterator<KItemListWidget*, KItemListGroupHeader*> it(m_visibleGroups);
1758         while (it.hasNext()) {
1759             it.next();
1760             updateGroupHeaderLayout(it.key());
1761         }
1762     }
1763
1764     emitOffsetChanges();
1765 }
1766
1767 QList<int> KItemListView::recycleInvisibleItems(int firstVisibleIndex,
1768                                                 int lastVisibleIndex,
1769                                                 LayoutAnimationHint hint)
1770 {
1771     // Determine all items that are completely invisible and might be
1772     // reused for items that just got (at least partly) visible. If the
1773     // animation hint is set to 'Animation' items that do e.g. an animated
1774     // moving of their position are not marked as invisible: This assures
1775     // that a scrolling inside the view can be done without breaking an animation.
1776
1777     QList<int> items;
1778
1779     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
1780     while (it.hasNext()) {
1781         it.next();
1782
1783         KItemListWidget* widget = it.value();
1784         const int index = widget->index();
1785         const bool invisible = (index < firstVisibleIndex) || (index > lastVisibleIndex);
1786
1787         if (invisible) {
1788             if (m_animation->isStarted(widget)) {
1789                 if (hint == NoAnimation) {
1790                     // Stopping the animation will call KItemListView::slotAnimationFinished()
1791                     // and the widget will be recycled if necessary there.
1792                     m_animation->stop(widget);
1793                 }
1794             } else {
1795                 widget->setVisible(false);
1796                 items.append(index);
1797
1798                 if (m_grouped) {
1799                     recycleGroupHeaderForWidget(widget);
1800                 }
1801             }
1802         }
1803     }
1804
1805     return items;
1806 }
1807
1808 bool KItemListView::moveWidget(KItemListWidget* widget,const QPointF& newPos)
1809 {
1810     if (widget->pos() == newPos) {
1811         return false;
1812     }
1813
1814     bool startMovingAnim = false;
1815
1816     if (m_itemSize.isEmpty()) {
1817         // The items are not aligned in a grid but either as columns or rows.
1818         startMovingAnim = true;
1819     } else {
1820         // When having a grid the moving-animation should only be started, if it is done within
1821         // one row in the vertical scroll-orientation or one column in the horizontal scroll-orientation.
1822         // Otherwise instead of a moving-animation a create-animation on the new position will be used
1823         // instead. This is done to prevent overlapping (and confusing) moving-animations.
1824         const int index = widget->index();
1825         const Cell cell = m_visibleCells.value(index);
1826         if (cell.column >= 0 && cell.row >= 0) {
1827             if (scrollOrientation() == Qt::Vertical) {
1828                 startMovingAnim = (cell.row == m_layouter->itemRow(index));
1829             } else {
1830                 startMovingAnim = (cell.column == m_layouter->itemColumn(index));
1831             }
1832         }
1833     }
1834
1835     if (startMovingAnim) {
1836         m_animation->start(widget, KItemListViewAnimation::MovingAnimation, newPos);
1837         return true;
1838     }
1839
1840     m_animation->stop(widget);
1841     m_animation->start(widget, KItemListViewAnimation::CreateAnimation);
1842     return false;
1843 }
1844
1845 void KItemListView::emitOffsetChanges()
1846 {
1847     const qreal newScrollOffset = m_layouter->scrollOffset();
1848     if (m_oldScrollOffset != newScrollOffset) {
1849         emit scrollOffsetChanged(newScrollOffset, m_oldScrollOffset);
1850         m_oldScrollOffset = newScrollOffset;
1851     }
1852
1853     const qreal newMaximumScrollOffset = m_layouter->maximumScrollOffset();
1854     if (m_oldMaximumScrollOffset != newMaximumScrollOffset) {
1855         emit maximumScrollOffsetChanged(newMaximumScrollOffset, m_oldMaximumScrollOffset);
1856         m_oldMaximumScrollOffset = newMaximumScrollOffset;
1857     }
1858
1859     const qreal newItemOffset = m_layouter->itemOffset();
1860     if (m_oldItemOffset != newItemOffset) {
1861         emit itemOffsetChanged(newItemOffset, m_oldItemOffset);
1862         m_oldItemOffset = newItemOffset;
1863     }
1864
1865     const qreal newMaximumItemOffset = m_layouter->maximumItemOffset();
1866     if (m_oldMaximumItemOffset != newMaximumItemOffset) {
1867         emit maximumItemOffsetChanged(newMaximumItemOffset, m_oldMaximumItemOffset);
1868         m_oldMaximumItemOffset = newMaximumItemOffset;
1869     }
1870 }
1871
1872 KItemListWidget* KItemListView::createWidget(int index)
1873 {
1874     KItemListWidget* widget = widgetCreator()->create(this);
1875     widget->setFlag(QGraphicsItem::ItemStacksBehindParent);
1876
1877     m_visibleItems.insert(index, widget);
1878     m_visibleCells.insert(index, Cell());
1879     updateWidgetProperties(widget, index);
1880     initializeItemListWidget(widget);
1881     return widget;
1882 }
1883
1884 void KItemListView::recycleWidget(KItemListWidget* widget)
1885 {
1886     if (m_grouped) {
1887         recycleGroupHeaderForWidget(widget);
1888     }
1889
1890     const int index = widget->index();
1891     m_visibleItems.remove(index);
1892     m_visibleCells.remove(index);
1893
1894     widgetCreator()->recycle(widget);
1895 }
1896
1897 void KItemListView::setWidgetIndex(KItemListWidget* widget, int index)
1898 {
1899     const int oldIndex = widget->index();
1900     m_visibleItems.remove(oldIndex);
1901     m_visibleCells.remove(oldIndex);
1902
1903     m_visibleItems.insert(index, widget);
1904     m_visibleCells.insert(index, Cell());
1905
1906     widget->setIndex(index);
1907 }
1908
1909 void KItemListView::moveWidgetToIndex(KItemListWidget* widget, int index)
1910 {
1911     const int oldIndex = widget->index();
1912     const Cell oldCell = m_visibleCells.value(oldIndex);
1913
1914     setWidgetIndex(widget, index);
1915
1916     const Cell newCell(m_layouter->itemColumn(index), m_layouter->itemRow(index));
1917     const bool vertical = (scrollOrientation() == Qt::Vertical);
1918     const bool updateCell = (vertical  && oldCell.row    == newCell.row) ||
1919                             (!vertical && oldCell.column == newCell.column);
1920     if (updateCell) {
1921         m_visibleCells.insert(index, newCell);
1922     }
1923 }
1924
1925 void KItemListView::setLayouterSize(const QSizeF& size, SizeType sizeType)
1926 {
1927     switch (sizeType) {
1928     case LayouterSize: m_layouter->setSize(size); break;
1929     case ItemSize: m_layouter->setItemSize(size); break;
1930     default: break;
1931     }
1932 }
1933
1934 void KItemListView::updateWidgetProperties(KItemListWidget* widget, int index)
1935 {
1936     widget->setVisibleRoles(m_visibleRoles);
1937     updateWidgetColumnWidths(widget);
1938     widget->setStyleOption(m_styleOption);
1939
1940     const KItemListSelectionManager* selectionManager = m_controller->selectionManager();
1941     widget->setCurrent(index == selectionManager->currentItem());
1942     widget->setSelected(selectionManager->isSelected(index));
1943     widget->setHovered(false);
1944     widget->setEnabledSelectionToggle(enabledSelectionToggles());
1945     widget->setIndex(index);
1946     widget->setData(m_model->data(index));
1947     widget->setSiblingsInformation(QBitArray());
1948     updateAlternateBackgroundForWidget(widget);
1949
1950     if (m_grouped) {
1951         updateGroupHeaderForWidget(widget);
1952     }
1953 }
1954
1955 void KItemListView::updateGroupHeaderForWidget(KItemListWidget* widget)
1956 {
1957     Q_ASSERT(m_grouped);
1958
1959     const int index = widget->index();
1960     if (!m_layouter->isFirstGroupItem(index)) {
1961         // The widget does not represent the first item of a group
1962         // and hence requires no header
1963         recycleGroupHeaderForWidget(widget);
1964         return;
1965     }
1966
1967     const QList<QPair<int, QVariant> > groups = model()->groups();
1968     if (groups.isEmpty() || !groupHeaderCreator()) {
1969         return;
1970     }
1971
1972     KItemListGroupHeader* groupHeader = m_visibleGroups.value(widget);
1973     if (!groupHeader) {
1974         groupHeader = groupHeaderCreator()->create(this);
1975         groupHeader->setParentItem(widget);
1976         m_visibleGroups.insert(widget, groupHeader);
1977         connect(widget, SIGNAL(geometryChanged()), this, SLOT(slotGeometryOfGroupHeaderParentChanged()));
1978     }
1979     Q_ASSERT(groupHeader->parentItem() == widget);
1980
1981     const int groupIndex = groupIndexForItem(index);
1982     Q_ASSERT(groupIndex >= 0);
1983     groupHeader->setData(groups.at(groupIndex).second);
1984     groupHeader->setRole(model()->sortRole());
1985     groupHeader->setStyleOption(m_styleOption);
1986     groupHeader->setScrollOrientation(scrollOrientation());
1987     groupHeader->setItemIndex(index);
1988
1989     groupHeader->show();
1990 }
1991
1992 void KItemListView::updateGroupHeaderLayout(KItemListWidget* widget)
1993 {
1994     KItemListGroupHeader* groupHeader = m_visibleGroups.value(widget);
1995     Q_ASSERT(groupHeader);
1996
1997     const int index = widget->index();
1998     const QRectF groupHeaderRect = m_layouter->groupHeaderRect(index);
1999     const QRectF itemRect = m_layouter->itemRect(index);
2000
2001     // The group-header is a child of the itemlist widget. Translate the
2002     // group header position to the relative position.
2003     if (scrollOrientation() == Qt::Vertical) {
2004         // In the vertical scroll orientation the group header should always span
2005         // the whole width no matter which temporary position the parent widget
2006         // has. In this case the x-position and width will be adjusted manually.
2007         const qreal x = -widget->x() - itemOffset();
2008         const qreal width = maximumItemOffset();
2009         groupHeader->setPos(x, -groupHeaderRect.height());
2010         groupHeader->resize(width, groupHeaderRect.size().height());
2011     } else {
2012         groupHeader->setPos(groupHeaderRect.x() - itemRect.x(), -widget->y());
2013         groupHeader->resize(groupHeaderRect.size());
2014     }
2015 }
2016
2017 void KItemListView::recycleGroupHeaderForWidget(KItemListWidget* widget)
2018 {
2019     KItemListGroupHeader* header = m_visibleGroups.value(widget);
2020     if (header) {
2021         header->setParentItem(0);
2022         groupHeaderCreator()->recycle(header);
2023         m_visibleGroups.remove(widget);
2024         disconnect(widget, SIGNAL(geometryChanged()), this, SLOT(slotGeometryOfGroupHeaderParentChanged()));
2025     }
2026 }
2027
2028 void KItemListView::updateVisibleGroupHeaders()
2029 {
2030     Q_ASSERT(m_grouped);
2031     m_layouter->markAsDirty();
2032
2033     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2034     while (it.hasNext()) {
2035         it.next();
2036         updateGroupHeaderForWidget(it.value());
2037     }
2038 }
2039
2040 int KItemListView::groupIndexForItem(int index) const
2041 {
2042     Q_ASSERT(m_grouped);
2043
2044     const QList<QPair<int, QVariant> > groups = model()->groups();
2045     if (groups.isEmpty()) {
2046         return -1;
2047     }
2048
2049     int min = 0;
2050     int max = groups.count() - 1;
2051     int mid = 0;
2052     do {
2053         mid = (min + max) / 2;
2054         if (index > groups[mid].first) {
2055             min = mid + 1;
2056         } else {
2057             max = mid - 1;
2058         }
2059     } while (groups[mid].first != index && min <= max);
2060
2061     if (min > max) {
2062         while (groups[mid].first > index && mid > 0) {
2063             --mid;
2064         }
2065     }
2066
2067     return mid;
2068 }
2069
2070 void KItemListView::updateAlternateBackgrounds()
2071 {
2072     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2073     while (it.hasNext()) {
2074         it.next();
2075         updateAlternateBackgroundForWidget(it.value());
2076     }
2077 }
2078
2079 void KItemListView::updateAlternateBackgroundForWidget(KItemListWidget* widget)
2080 {
2081     bool enabled = useAlternateBackgrounds();
2082     if (enabled) {
2083         const int index = widget->index();
2084         enabled = (index & 0x1) > 0;
2085         if (m_grouped) {
2086             const int groupIndex = groupIndexForItem(index);
2087             if (groupIndex >= 0) {
2088                 const QList<QPair<int, QVariant> > groups = model()->groups();
2089                 const int indexOfFirstGroupItem = groups[groupIndex].first;
2090                 const int relativeIndex = index - indexOfFirstGroupItem;
2091                 enabled = (relativeIndex & 0x1) > 0;
2092             }
2093         }
2094     }
2095     widget->setAlternateBackground(enabled);
2096 }
2097
2098 bool KItemListView::useAlternateBackgrounds() const
2099 {
2100     return m_itemSize.isEmpty() && m_visibleRoles.count() > 1;
2101 }
2102
2103 QHash<QByteArray, qreal> KItemListView::preferredColumnWidths(const KItemRangeList& itemRanges) const
2104 {
2105     QElapsedTimer timer;
2106     timer.start();
2107
2108     QHash<QByteArray, qreal> widths;
2109
2110     // Calculate the minimum width for each column that is required
2111     // to show the headline unclipped.
2112     const QFontMetricsF fontMetrics(m_headerWidget->font());
2113     const int gripMargin   = m_headerWidget->style()->pixelMetric(QStyle::PM_HeaderGripMargin);
2114     const int headerMargin = m_headerWidget->style()->pixelMetric(QStyle::PM_HeaderMargin);
2115     foreach (const QByteArray& visibleRole, visibleRoles()) {
2116         const QString headerText = m_model->roleDescription(visibleRole);
2117         const qreal headerWidth = fontMetrics.width(headerText) + gripMargin + headerMargin * 2;
2118         widths.insert(visibleRole, headerWidth);
2119     }
2120
2121     // Calculate the preferred column withs for each item and ignore values
2122     // smaller than the width for showing the headline unclipped.
2123     const KItemListWidgetCreatorBase* creator = widgetCreator();
2124     int calculatedItemCount = 0;
2125     bool maxTimeExceeded = false;
2126     foreach (const KItemRange& itemRange, itemRanges) {
2127         const int startIndex = itemRange.index;
2128         const int endIndex = startIndex + itemRange.count - 1;
2129
2130         for (int i = startIndex; i <= endIndex; ++i) {
2131             foreach (const QByteArray& visibleRole, visibleRoles()) {
2132                 qreal maxWidth = widths.value(visibleRole, 0);
2133                 const qreal width = creator->preferredRoleColumnWidth(visibleRole, i, this);
2134                 maxWidth = qMax(width, maxWidth);
2135                 widths.insert(visibleRole, maxWidth);
2136             }
2137
2138             if (calculatedItemCount > 100 && timer.elapsed() > 200) {
2139                 // When having several thousands of items calculating the sizes can get
2140                 // very expensive. We accept a possibly too small role-size in favour
2141                 // of having no blocking user interface.
2142                 maxTimeExceeded = true;
2143                 break;
2144             }
2145             ++calculatedItemCount;
2146         }
2147         if (maxTimeExceeded) {
2148             break;
2149         }
2150     }
2151
2152     return widths;
2153 }
2154
2155 void KItemListView::applyColumnWidthsFromHeader()
2156 {
2157     // Apply the new size to the layouter
2158     const qreal requiredWidth = columnWidthsSum();
2159     const QSizeF dynamicItemSize(qMax(size().width(), requiredWidth),
2160                                  m_itemSize.height());
2161     m_layouter->setItemSize(dynamicItemSize);
2162
2163     // Update the role sizes for all visible widgets
2164     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2165     while (it.hasNext()) {
2166         it.next();
2167         updateWidgetColumnWidths(it.value());
2168     }
2169 }
2170
2171 void KItemListView::updateWidgetColumnWidths(KItemListWidget* widget)
2172 {
2173     foreach (const QByteArray& role, m_visibleRoles) {
2174         widget->setColumnWidth(role, m_headerWidget->columnWidth(role));
2175     }
2176 }
2177
2178 void KItemListView::updatePreferredColumnWidths(const KItemRangeList& itemRanges)
2179 {
2180     Q_ASSERT(m_itemSize.isEmpty());
2181     const int itemCount = m_model->count();
2182     int rangesItemCount = 0;
2183     foreach (const KItemRange& range, itemRanges) {
2184         rangesItemCount += range.count;
2185     }
2186
2187     if (itemCount == rangesItemCount) {
2188         const QHash<QByteArray, qreal> preferredWidths = preferredColumnWidths(itemRanges);
2189         foreach (const QByteArray& role, m_visibleRoles) {
2190             m_headerWidget->setPreferredColumnWidth(role, preferredWidths.value(role));
2191         }
2192     } else {
2193         // Only a sub range of the roles need to be determined.
2194         // The chances are good that the widths of the sub ranges
2195         // already fit into the available widths and hence no
2196         // expensive update might be required.
2197         bool changed = false;
2198
2199         const QHash<QByteArray, qreal> updatedWidths = preferredColumnWidths(itemRanges);
2200         QHashIterator<QByteArray, qreal> it(updatedWidths);
2201         while (it.hasNext()) {
2202             it.next();
2203             const QByteArray& role = it.key();
2204             const qreal updatedWidth = it.value();
2205             const qreal currentWidth = m_headerWidget->preferredColumnWidth(role);
2206             if (updatedWidth > currentWidth) {
2207                 m_headerWidget->setPreferredColumnWidth(role, updatedWidth);
2208                 changed = true;
2209             }
2210         }
2211
2212         if (!changed) {
2213             // All the updated sizes are smaller than the current sizes and no change
2214             // of the stretched roles-widths is required
2215             return;
2216         }
2217     }
2218
2219     if (m_headerWidget->automaticColumnResizing()) {
2220         applyAutomaticColumnWidths();
2221     }
2222 }
2223
2224 void KItemListView::updatePreferredColumnWidths()
2225 {
2226     if (m_model) {
2227         updatePreferredColumnWidths(KItemRangeList() << KItemRange(0, m_model->count()));
2228     }
2229 }
2230
2231 void KItemListView::applyAutomaticColumnWidths()
2232 {
2233     Q_ASSERT(m_itemSize.isEmpty());
2234     Q_ASSERT(m_headerWidget->automaticColumnResizing());
2235     if (m_visibleRoles.isEmpty()) {
2236         return;
2237     }
2238
2239     // Calculate the maximum size of an item by considering the
2240     // visible role sizes and apply them to the layouter. If the
2241     // size does not use the available view-size the size of the
2242     // first role will get stretched.
2243
2244     foreach (const QByteArray& role, m_visibleRoles) {
2245         const qreal preferredWidth = m_headerWidget->preferredColumnWidth(role);
2246         m_headerWidget->setColumnWidth(role, preferredWidth);
2247     }
2248
2249     const QByteArray firstRole = m_visibleRoles.first();
2250     qreal firstColumnWidth = m_headerWidget->columnWidth(firstRole);
2251     QSizeF dynamicItemSize = m_itemSize;
2252
2253     qreal requiredWidth = columnWidthsSum();
2254     const qreal availableWidth = size().width();
2255     if (requiredWidth < availableWidth) {
2256         // Stretch the first column to use the whole remaining width
2257         firstColumnWidth += availableWidth - requiredWidth;
2258         m_headerWidget->setColumnWidth(firstRole, firstColumnWidth);
2259     } else if (requiredWidth > availableWidth && m_visibleRoles.count() > 1) {
2260         // Shrink the first column to be able to show as much other
2261         // columns as possible
2262         qreal shrinkedFirstColumnWidth = firstColumnWidth - requiredWidth + availableWidth;
2263
2264         // TODO: A proper calculation of the minimum width depends on the implementation
2265         // of KItemListWidget. Probably a kind of minimum size-hint should be introduced
2266         // later.
2267         const qreal minWidth = qMin(firstColumnWidth, qreal(m_styleOption.iconSize * 2 + 200));
2268         if (shrinkedFirstColumnWidth < minWidth) {
2269             shrinkedFirstColumnWidth = minWidth;
2270         }
2271
2272         m_headerWidget->setColumnWidth(firstRole, shrinkedFirstColumnWidth);
2273         requiredWidth -= firstColumnWidth - shrinkedFirstColumnWidth;
2274     }
2275
2276     dynamicItemSize.rwidth() = qMax(requiredWidth, availableWidth);
2277
2278     m_layouter->setItemSize(dynamicItemSize);
2279
2280     // Update the role sizes for all visible widgets
2281     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2282     while (it.hasNext()) {
2283         it.next();
2284         updateWidgetColumnWidths(it.value());
2285     }
2286 }
2287
2288 qreal KItemListView::columnWidthsSum() const
2289 {
2290     qreal widthsSum = 0;
2291     foreach (const QByteArray& role, m_visibleRoles) {
2292         widthsSum += m_headerWidget->columnWidth(role);
2293     }
2294     return widthsSum;
2295 }
2296
2297 QRectF KItemListView::headerBoundaries() const
2298 {
2299     return m_headerWidget->isVisible() ? m_headerWidget->geometry() : QRectF();
2300 }
2301
2302 bool KItemListView::changesItemGridLayout(const QSizeF& newGridSize,
2303                                           const QSizeF& newItemSize,
2304                                           const QSizeF& newItemMargin) const
2305 {
2306     if (newItemSize.isEmpty() || newGridSize.isEmpty()) {
2307         return false;
2308     }
2309
2310     if (m_layouter->scrollOrientation() == Qt::Vertical) {
2311         const qreal itemWidth = m_layouter->itemSize().width();
2312         if (itemWidth > 0) {
2313             const int newColumnCount = itemsPerSize(newGridSize.width(),
2314                                                     newItemSize.width(),
2315                                                     newItemMargin.width());
2316             if (m_model->count() > newColumnCount) {
2317                 const int oldColumnCount = itemsPerSize(m_layouter->size().width(),
2318                                                         itemWidth,
2319                                                         m_layouter->itemMargin().width());
2320                 return oldColumnCount != newColumnCount;
2321             }
2322         }
2323     } else {
2324         const qreal itemHeight = m_layouter->itemSize().height();
2325         if (itemHeight > 0) {
2326             const int newRowCount = itemsPerSize(newGridSize.height(),
2327                                                  newItemSize.height(),
2328                                                  newItemMargin.height());
2329             if (m_model->count() > newRowCount) {
2330                 const int oldRowCount = itemsPerSize(m_layouter->size().height(),
2331                                                      itemHeight,
2332                                                      m_layouter->itemMargin().height());
2333                 return oldRowCount != newRowCount;
2334             }
2335         }
2336     }
2337
2338     return false;
2339 }
2340
2341 bool KItemListView::animateChangedItemCount(int changedItemCount) const
2342 {
2343     if (m_itemSize.isEmpty()) {
2344         // We have only columns or only rows, but no grid: An animation is usually
2345         // welcome when inserting or removing items.
2346         return !supportsItemExpanding();
2347     }
2348
2349     if (m_layouter->size().isEmpty() || m_layouter->itemSize().isEmpty()) {
2350         return false;
2351     }
2352
2353     const int maximum = (scrollOrientation() == Qt::Vertical)
2354                         ? m_layouter->size().width()  / m_layouter->itemSize().width()
2355                         : m_layouter->size().height() / m_layouter->itemSize().height();
2356     // Only animate if up to 2/3 of a row or column are inserted or removed
2357     return changedItemCount <= maximum * 2 / 3;
2358 }
2359
2360
2361 bool KItemListView::scrollBarRequired(const QSizeF& size) const
2362 {
2363     const QSizeF oldSize = m_layouter->size();
2364
2365     m_layouter->setSize(size);
2366     const qreal maxOffset = m_layouter->maximumScrollOffset();
2367     m_layouter->setSize(oldSize);
2368
2369     return m_layouter->scrollOrientation() == Qt::Vertical ? maxOffset > size.height()
2370                                                            : maxOffset > size.width();
2371 }
2372
2373 int KItemListView::showDropIndicator(const QPointF& pos)
2374 {
2375     QHashIterator<int, KItemListWidget*> it(m_visibleItems);
2376     while (it.hasNext()) {
2377         it.next();
2378         const KItemListWidget* widget = it.value();
2379
2380         const QPointF mappedPos = widget->mapFromItem(this, pos);
2381         const QRectF rect = itemRect(widget->index());
2382         if (mappedPos.y() >= 0 && mappedPos.y() <= rect.height()) {
2383             if (m_model->supportsDropping(widget->index())) {
2384                 // Keep 30% of the rectangle as the gap instead of always having a fixed gap
2385                 const int gap = qMax(4.0, 0.3 * rect.height());
2386                 if (mappedPos.y() >= gap && mappedPos.y() <= rect.height() - gap) {
2387                     return -1;
2388                 }
2389             }
2390
2391             const bool isAboveItem = (mappedPos.y () < rect.height() / 2);
2392             const qreal y = isAboveItem ? rect.top() : rect.bottom();
2393
2394             const QRectF draggingInsertIndicator(rect.left(), y, rect.width(), 1);
2395             if (m_dropIndicator != draggingInsertIndicator) {
2396                 m_dropIndicator = draggingInsertIndicator;
2397                 update();
2398             }
2399
2400             int index = widget->index();
2401             if (!isAboveItem) {
2402                 ++index;
2403             }
2404             return index;
2405         }
2406     }
2407
2408     const QRectF firstItemRect = itemRect(firstVisibleIndex());
2409     return (pos.y() <= firstItemRect.top()) ? 0 : -1;
2410 }
2411
2412 void KItemListView::hideDropIndicator()
2413 {
2414     if (!m_dropIndicator.isNull()) {
2415         m_dropIndicator = QRectF();
2416         update();
2417     }
2418 }
2419
2420 void KItemListView::updateGroupHeaderHeight()
2421 {
2422     qreal groupHeaderHeight = m_styleOption.fontMetrics.height();
2423     qreal groupHeaderMargin = 0;
2424
2425     if (scrollOrientation() == Qt::Horizontal) {
2426         // The vertical margin above and below the header should be
2427         // equal to the horizontal margin, not the vertical margin
2428         // from m_styleOption.
2429         groupHeaderHeight += 2 * m_styleOption.horizontalMargin;
2430         groupHeaderMargin = m_styleOption.horizontalMargin;
2431     } else if (m_itemSize.isEmpty()){
2432         groupHeaderHeight += 4 * m_styleOption.padding;
2433         groupHeaderMargin = m_styleOption.iconSize / 2;
2434     } else {
2435         groupHeaderHeight += 2 * m_styleOption.padding + m_styleOption.verticalMargin;
2436         groupHeaderMargin = m_styleOption.iconSize / 4;
2437     }
2438     m_layouter->setGroupHeaderHeight(groupHeaderHeight);
2439     m_layouter->setGroupHeaderMargin(groupHeaderMargin);
2440
2441     updateVisibleGroupHeaders();
2442 }
2443
2444 void KItemListView::updateSiblingsInformation(int firstIndex, int lastIndex)
2445 {
2446     if (!supportsItemExpanding() || !m_model) {
2447         return;
2448     }
2449
2450     if (firstIndex < 0 || lastIndex < 0) {
2451         firstIndex = m_layouter->firstVisibleIndex();
2452         lastIndex  = m_layouter->lastVisibleIndex();
2453     } else {
2454         const bool isRangeVisible = (firstIndex <= m_layouter->lastVisibleIndex() &&
2455                                      lastIndex  >= m_layouter->firstVisibleIndex());
2456         if (!isRangeVisible) {
2457             return;
2458         }
2459     }
2460
2461     int previousParents = 0;
2462     QBitArray previousSiblings;
2463
2464     // The rootIndex describes the first index where the siblings get
2465     // calculated from. For the calculation the upper most parent item
2466     // is required. For performance reasons it is checked first whether
2467     // the visible items before or after the current range already
2468     // contain a siblings information which can be used as base.
2469     int rootIndex = firstIndex;
2470
2471     KItemListWidget* widget = m_visibleItems.value(firstIndex - 1);
2472     if (!widget) {
2473         // There is no visible widget before the range, check whether there
2474         // is one after the range:
2475         widget = m_visibleItems.value(lastIndex + 1);
2476         if (widget) {
2477             // The sibling information of the widget may only be used if
2478             // all items of the range have the same number of parents.
2479             const int parents = m_model->expandedParentsCount(lastIndex + 1);
2480             for (int i = lastIndex; i >= firstIndex; --i) {
2481                 if (m_model->expandedParentsCount(i) != parents) {
2482                     widget = 0;
2483                     break;
2484                 }
2485             }
2486         }
2487     }
2488
2489     if (widget) {
2490         // Performance optimization: Use the sibling information of the visible
2491         // widget beside the given range.
2492         previousSiblings = widget->siblingsInformation();
2493         if (previousSiblings.isEmpty()) {
2494             return;
2495         }
2496         previousParents = previousSiblings.count() - 1;
2497         previousSiblings.truncate(previousParents);
2498     } else {
2499         // Potentially slow path: Go back to the upper most parent of firstIndex
2500         // to be able to calculate the initial value for the siblings.
2501         while (rootIndex > 0 && m_model->expandedParentsCount(rootIndex) > 0) {
2502             --rootIndex;
2503         }
2504     }
2505
2506     Q_ASSERT(previousParents >= 0);
2507     for (int i = rootIndex; i <= lastIndex; ++i) {
2508         // Update the parent-siblings in case if the current item represents
2509         // a child or an upper parent.
2510         const int currentParents = m_model->expandedParentsCount(i);
2511         Q_ASSERT(currentParents >= 0);
2512         if (previousParents < currentParents) {
2513             previousParents = currentParents;
2514             previousSiblings.resize(currentParents);
2515             previousSiblings.setBit(currentParents - 1, hasSiblingSuccessor(i - 1));
2516         } else if (previousParents > currentParents) {
2517             previousParents = currentParents;
2518             previousSiblings.truncate(currentParents);
2519         }
2520
2521         if (i >= firstIndex) {
2522             // The index represents a visible item. Apply the parent-siblings
2523             // and update the sibling of the current item.
2524             KItemListWidget* widget = m_visibleItems.value(i);
2525             if (!widget) {
2526                 continue;
2527             }
2528
2529             QBitArray siblings = previousSiblings;
2530             siblings.resize(siblings.count() + 1);
2531             siblings.setBit(siblings.count() - 1, hasSiblingSuccessor(i));
2532
2533             widget->setSiblingsInformation(siblings);
2534         }
2535     }
2536 }
2537
2538 bool KItemListView::hasSiblingSuccessor(int index) const
2539 {
2540     bool hasSuccessor = false;
2541     const int parentsCount = m_model->expandedParentsCount(index);
2542     int successorIndex = index + 1;
2543
2544     // Search the next sibling
2545     const int itemCount = m_model->count();
2546     while (successorIndex < itemCount) {
2547         const int currentParentsCount = m_model->expandedParentsCount(successorIndex);
2548         if (currentParentsCount == parentsCount) {
2549             hasSuccessor = true;
2550             break;
2551         } else if (currentParentsCount < parentsCount) {
2552             break;
2553         }
2554         ++successorIndex;
2555     }
2556
2557     if (m_grouped && hasSuccessor) {
2558         // If the sibling is part of another group, don't mark it as
2559         // successor as the group header is between the sibling connections.
2560         for (int i = index + 1; i <= successorIndex; ++i) {
2561             if (m_layouter->isFirstGroupItem(i)) {
2562                 hasSuccessor = false;
2563                 break;
2564             }
2565         }
2566     }
2567
2568     return hasSuccessor;
2569 }
2570
2571 void KItemListView::disconnectRoleEditingSignals(int index)
2572 {
2573     KItemListWidget* widget = m_visibleItems.value(index);
2574     if (!widget) {
2575         return;
2576     }
2577
2578     widget->disconnect(SIGNAL(roleEditingCanceled(int,QByteArray,QVariant)), this);
2579     widget->disconnect(SIGNAL(roleEditingFinished(int,QByteArray,QVariant)), this);
2580 }
2581
2582 int KItemListView::calculateAutoScrollingIncrement(int pos, int range, int oldInc)
2583 {
2584     int inc = 0;
2585
2586     const int minSpeed = 4;
2587     const int maxSpeed = 128;
2588     const int speedLimiter = 96;
2589     const int autoScrollBorder = 64;
2590
2591     // Limit the increment that is allowed to be added in comparison to 'oldInc'.
2592     // This assures that the autoscrolling speed grows gradually.
2593     const int incLimiter = 1;
2594
2595     if (pos < autoScrollBorder) {
2596         inc = -minSpeed + qAbs(pos - autoScrollBorder) * (pos - autoScrollBorder) / speedLimiter;
2597         inc = qMax(inc, -maxSpeed);
2598         inc = qMax(inc, oldInc - incLimiter);
2599     } else if (pos > range - autoScrollBorder) {
2600         inc = minSpeed + qAbs(pos - range + autoScrollBorder) * (pos - range + autoScrollBorder) / speedLimiter;
2601         inc = qMin(inc, maxSpeed);
2602         inc = qMin(inc, oldInc + incLimiter);
2603     }
2604
2605     return inc;
2606 }
2607
2608 int KItemListView::itemsPerSize(qreal size, qreal itemSize, qreal itemMargin)
2609 {
2610     const qreal availableSize = size - itemMargin;
2611     const int count = availableSize / (itemSize + itemMargin);
2612     return count;
2613 }
2614
2615
2616
2617 KItemListCreatorBase::~KItemListCreatorBase()
2618 {
2619     qDeleteAll(m_recycleableWidgets);
2620     qDeleteAll(m_createdWidgets);
2621 }
2622
2623 void KItemListCreatorBase::addCreatedWidget(QGraphicsWidget* widget)
2624 {
2625     m_createdWidgets.insert(widget);
2626 }
2627
2628 void KItemListCreatorBase::pushRecycleableWidget(QGraphicsWidget* widget)
2629 {
2630     Q_ASSERT(m_createdWidgets.contains(widget));
2631     m_createdWidgets.remove(widget);
2632
2633     if (m_recycleableWidgets.count() < 100) {
2634         m_recycleableWidgets.append(widget);
2635         widget->setVisible(false);
2636     } else {
2637         delete widget;
2638     }
2639 }
2640
2641 QGraphicsWidget* KItemListCreatorBase::popRecycleableWidget()
2642 {
2643     if (m_recycleableWidgets.isEmpty()) {
2644         return 0;
2645     }
2646
2647     QGraphicsWidget* widget = m_recycleableWidgets.takeLast();
2648     m_createdWidgets.insert(widget);
2649     return widget;
2650 }
2651
2652 KItemListWidgetCreatorBase::~KItemListWidgetCreatorBase()
2653 {
2654 }
2655
2656 void KItemListWidgetCreatorBase::recycle(KItemListWidget* widget)
2657 {
2658     widget->setParentItem(0);
2659     widget->setOpacity(1.0);
2660     pushRecycleableWidget(widget);
2661 }
2662
2663 KItemListGroupHeaderCreatorBase::~KItemListGroupHeaderCreatorBase()
2664 {
2665 }
2666
2667 void KItemListGroupHeaderCreatorBase::recycle(KItemListGroupHeader* header)
2668 {
2669     header->setOpacity(1.0);
2670     pushRecycleableWidget(header);
2671 }
2672
2673 #include "kitemlistview.moc"