src/kitemviews/kitemlistcontroller.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 "kitemlistcontroller.h"
  24
  25 #include "kitemlistview.h"
  26 #include "kitemlistrubberband_p.h"
  27 #include "kitemlistselectionmanager.h"
  28
  29 #include <QEvent>
  30 #include <QGraphicsSceneEvent>
  31
  32 #include <KDebug>
  33
  34 KItemListController::KItemListController(QObject* parent) :
  35     QObject(parent),
  36     m_selectionBehavior(NoSelection),
  37     m_model(0),
  38     m_view(0),
  39     m_selectionManager(new KItemListSelectionManager(this)),
  40     m_pressedIndex(-1)
  41 {
  42 }
  43
  44 KItemListController::~KItemListController()
  45 {
  46 }
  47
  48 void KItemListController::setModel(KItemModelBase* model)
  49 {
  50     if (m_model == model) {
  51         return;
  52     }
  53
  54     KItemModelBase* oldModel = m_model;
  55     m_model = model;
  56
  57     if (m_view) {
  58         m_view->setModel(m_model);
  59     }
  60
  61     m_selectionManager->setModel(m_model);
  62
  63     emit modelChanged(m_model, oldModel);
  64 }
  65
  66 KItemModelBase* KItemListController::model() const
  67 {
  68     return m_model;
  69 }
  70
  71 KItemListSelectionManager* KItemListController::selectionManager() const
  72 {
  73     return m_selectionManager;
  74 }
  75
  76 void KItemListController::setView(KItemListView* view)
  77 {
  78     if (m_view == view) {
  79         return;
  80     }
  81
  82     KItemListView* oldView = m_view;
  83     if (oldView) {
  84         disconnect(oldView, SIGNAL(offsetChanged(qreal,qreal)), this, SLOT(slotViewOffsetChanged(qreal,qreal)));
  85     }
  86
  87     m_view = view;
  88
  89     if (m_view) {
  90         m_view->setController(this);
  91         m_view->setModel(m_model);
  92         connect(m_view, SIGNAL(offsetChanged(qreal,qreal)), this, SLOT(slotViewOffsetChanged(qreal,qreal)));
  93     }
  94
  95     emit viewChanged(m_view, oldView);
  96 }
  97
  98 KItemListView* KItemListController::view() const
  99 {
 100     return m_view;
 101 }
 102
 103 void KItemListController::setSelectionBehavior(SelectionBehavior behavior)
 104 {
 105     m_selectionBehavior = behavior;
 106 }
 107
 108 KItemListController::SelectionBehavior KItemListController::selectionBehavior() const
 109 {
 110     return m_selectionBehavior;
 111 }
 112
 113 bool KItemListController::showEvent(QShowEvent* event)
 114 {
 115     Q_UNUSED(event);
 116     return false;
 117 }
 118
 119 bool KItemListController::hideEvent(QHideEvent* event)
 120 {
 121     Q_UNUSED(event);
 122     return false;
 123 }
 124
 125 bool KItemListController::keyPressEvent(QKeyEvent* event)
 126 {
 127     const bool shiftPressed = event->modifiers() & Qt::ShiftModifier;
 128     const bool controlPressed = event->modifiers() & Qt::ControlModifier;
 129     const bool shiftOrControlPressed = shiftPressed || controlPressed;
 130
 131     int index = m_selectionManager->currentItem();
 132     const int itemCount = m_model->count();
 133     const int itemsPerRow = m_view->itemsPerOffset();
 134
 135     // For horizontal scroll orientation, transform
 136     // the arrow keys to simplify the event handling.
 137     int key = event->key();
 138     if (m_view->scrollOrientation() == Qt::Horizontal) {
 139         switch (key) {
 140         case Qt::Key_Up:    key = Qt::Key_Left; break;
 141         case Qt::Key_Down:  key = Qt::Key_Right; break;
 142         case Qt::Key_Left:  key = Qt::Key_Up; break;
 143         case Qt::Key_Right: key = Qt::Key_Down; break;
 144         default:            break;
 145         }
 146     }
 147
 148     switch (key) {
 149     case Qt::Key_Home:
 150         index = 0;
 151         break;
 152
 153     case Qt::Key_End:
 154         index = itemCount - 1;
 155         break;
 156
 157     case Qt::Key_Left:
 158         if (index > 0) {
 159             index--;
 160         }
 161         break;
 162
 163     case Qt::Key_Right:
 164         if (index < itemCount - 1) {
 165             index++;
 166         }
 167         break;
 168
 169     case Qt::Key_Up:
 170         if (index >= itemsPerRow) {
 171             index -= itemsPerRow;
 172         }
 173         break;
 174
 175     case Qt::Key_Down:
 176         if (index + itemsPerRow < itemCount) {
 177             // We are not in the last row yet.
 178             index += itemsPerRow;
 179         }
 180         else {
 181             // We are either in the last row already, or we are in the second-last row,
 182             // and there is no item below the current item.
 183             // In the latter case, we jump to the very last item.
 184             const int currentColumn = index % itemsPerRow;
 185             const int lastItemColumn = (itemCount - 1) % itemsPerRow;
 186             const bool inLastRow = currentColumn < lastItemColumn;
 187             if (!inLastRow) {
 188                 index = itemCount - 1;
 189             }
 190         }
 191         break;
 192
 193     case Qt::Key_Space:
 194         if (controlPressed) {
 195             m_selectionManager->endAnchoredSelection();
 196             m_selectionManager->setSelected(index, 1, KItemListSelectionManager::Toggle);
 197             m_selectionManager->beginAnchoredSelection(index);
 198         }
 199
 200     default:
 201         break;
 202     }
 203
 204     if (m_selectionManager->currentItem() != index) {
 205         if (controlPressed) {
 206             m_selectionManager->endAnchoredSelection();
 207         }
 208
 209         m_selectionManager->setCurrentItem(index);
 210
 211         if (!shiftOrControlPressed || m_selectionBehavior == SingleSelection) {
 212             m_selectionManager->clearSelection();
 213             m_selectionManager->setSelected(index, 1);
 214         }
 215
 216         if (!shiftPressed) {
 217             m_selectionManager->beginAnchoredSelection(index);
 218         }
 219     }
 220     return true;
 221 }
 222
 223 bool KItemListController::inputMethodEvent(QInputMethodEvent* event)
 224 {
 225     Q_UNUSED(event);
 226     return false;
 227 }
 228
 229 bool KItemListController::mousePressEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform)
 230 {
 231     if (!m_view) {
 232         return false;
 233     }
 234
 235     const QPointF pos = transform.map(event->pos());
 236     m_pressedIndex = m_view->itemAt(pos);
 237
 238     if (m_view->isAboveExpansionToggle(m_pressedIndex, pos)) {
 239         return true;
 240     }
 241
 242     const bool shiftPressed = event->modifiers() & Qt::ShiftModifier;
 243     const bool controlPressed = event->modifiers() & Qt::ControlModifier;
 244     const bool shiftOrControlPressed = shiftPressed || controlPressed;
 245
 246     if (!shiftOrControlPressed || m_selectionBehavior == SingleSelection) {
 247         m_selectionManager->clearSelection();
 248     }
 249
 250     if (!shiftPressed) {
 251         // Finish the anchored selection before the current index is changed
 252         m_selectionManager->endAnchoredSelection();
 253     }
 254
 255     if (m_pressedIndex >= 0) {
 256         m_selectionManager->setCurrentItem(m_pressedIndex);
 257
 258         switch (m_selectionBehavior) {
 259         case NoSelection:
 260             break;
 261
 262         case SingleSelection:
 263             m_selectionManager->setSelected(m_pressedIndex);
 264             break;
 265
 266         case MultiSelection:
 267             if (controlPressed) {
 268                 m_selectionManager->setSelected(m_pressedIndex, 1, KItemListSelectionManager::Toggle);
 269                 m_selectionManager->beginAnchoredSelection(m_pressedIndex);
 270             } else if (!shiftPressed || !m_selectionManager->isAnchoredSelectionActive()) {
 271                 // Select the pressed item and start a new anchored selection
 272                 m_selectionManager->setSelected(m_pressedIndex, 1, KItemListSelectionManager::Select);
 273                 m_selectionManager->beginAnchoredSelection(m_pressedIndex);
 274             }
 275             break;
 276
 277         default:
 278             Q_ASSERT(false);
 279             break;
 280         }
 281
 282         return true;
 283     } else {
 284         KItemListRubberBand* rubberBand = m_view->rubberBand();
 285         QPointF startPos = pos;
 286         if (m_view->scrollOrientation() == Qt::Vertical) {
 287             startPos.ry() += m_view->offset();
 288             if (m_view->itemSize().width() < 0) {
 289                 // Use a special rubberband for views that have only one column and
 290                 // expand the rubberband to use the whole width of the view.
 291                 startPos.setX(0);
 292             }
 293         } else {
 294             startPos.rx() += m_view->offset();
 295         }
 296         rubberBand->setStartPosition(startPos);
 297         rubberBand->setEndPosition(startPos);
 298         rubberBand->setActive(true);
 299         connect(rubberBand, SIGNAL(endPositionChanged(QPointF,QPointF)), this, SLOT(slotRubberBandChanged()));
 300     }
 301
 302     return false;
 303 }
 304
 305 bool KItemListController::mouseMoveEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform)
 306 {
 307     if (!m_view) {
 308         return false;
 309     }
 310
 311     KItemListRubberBand* rubberBand = m_view->rubberBand();
 312     if (rubberBand->isActive()) {
 313         QPointF endPos = transform.map(event->pos());
 314         if (m_view->scrollOrientation() == Qt::Vertical) {
 315             endPos.ry() += m_view->offset();
 316             if (m_view->itemSize().width() < 0) {
 317                 // Use a special rubberband for views that have only one column and
 318                 // expand the rubberband to use the whole width of the view.
 319                 endPos.setX(m_view->size().width());
 320             }
 321         } else {
 322             endPos.rx() += m_view->offset();
 323         }
 324         rubberBand->setEndPosition(endPos);
 325     }
 326
 327     return false;
 328 }
 329
 330 bool KItemListController::mouseReleaseEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform)
 331 {
 332     if (!m_view) {
 333         return false;
 334     }
 335
 336     KItemListRubberBand* rubberBand = m_view->rubberBand();
 337     if (rubberBand->isActive()) {
 338         disconnect(rubberBand, SIGNAL(endPositionChanged(QPointF,QPointF)), this, SLOT(slotRubberBandChanged()));
 339         rubberBand->setActive(false);
 340         m_pressedIndex = -1;
 341         return false;
 342     }
 343
 344     const QPointF pos = transform.map(event->pos());
 345     const int index = m_view->itemAt(pos);
 346     const bool shiftOrControlPressed = event->modifiers() & Qt::ShiftModifier || event->modifiers() & Qt::ControlModifier;
 347
 348     if (index >= 0 && index == m_pressedIndex) {
 349         // The release event is done above the same item as the press event
 350         bool emitItemClicked = true;
 351         if (event->button() & Qt::LeftButton) {
 352             if (m_view->isAboveExpansionToggle(index, pos)) {
 353                 emit itemExpansionToggleClicked(index);
 354                 emitItemClicked = false;
 355             }
 356             else if (shiftOrControlPressed) {
 357                 // The mouse click should only update the selection, not trigger the item
 358                 emitItemClicked = false;
 359             }
 360         }
 361
 362         if (emitItemClicked) {
 363             emit itemClicked(index, event->button());
 364         }
 365     } else if (!shiftOrControlPressed) {
 366         m_selectionManager->clearSelection();
 367     }
 368
 369     m_pressedIndex = -1;
 370     return false;
 371 }
 372
 373 bool KItemListController::mouseDoubleClickEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform)
 374 {
 375     Q_UNUSED(event);
 376     Q_UNUSED(transform);
 377     return false;
 378 }
 379
 380 bool KItemListController::dragEnterEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform)
 381 {
 382     Q_UNUSED(event);
 383     Q_UNUSED(transform);
 384     return false;
 385 }
 386
 387 bool KItemListController::dragLeaveEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform)
 388 {
 389     Q_UNUSED(event);
 390     Q_UNUSED(transform);
 391     return false;
 392 }
 393
 394 bool KItemListController::dragMoveEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform)
 395 {
 396     Q_UNUSED(event);
 397     Q_UNUSED(transform);
 398     return false;
 399 }
 400
 401 bool KItemListController::dropEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform)
 402 {
 403     Q_UNUSED(event);
 404     Q_UNUSED(transform);
 405     return false;
 406 }
 407
 408 bool KItemListController::hoverEnterEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform)
 409 {
 410     Q_UNUSED(event);
 411     Q_UNUSED(transform);
 412     return false;
 413 }
 414
 415 bool KItemListController::hoverMoveEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform)
 416 {
 417     // The implementation assumes that only one item can get hovered no matter
 418     // whether they overlap or not.
 419
 420     Q_UNUSED(transform);
 421     if (!m_model || !m_view) {
 422         return false;
 423     }
 424
 425     // Search the previously hovered item that might get unhovered
 426     KItemListWidget* unhoveredWidget = 0;
 427     foreach (KItemListWidget* widget, m_view->visibleItemListWidgets()) {
 428         if (widget->isHovered()) {
 429             unhoveredWidget = widget;
 430             break;
 431         }
 432     }
 433
 434     // Search the currently hovered item
 435     KItemListWidget* hoveredWidget = 0;
 436     foreach (KItemListWidget* widget, m_view->visibleItemListWidgets()) {
 437         const QPointF mappedPos = widget->mapFromItem(m_view, event->pos());
 438
 439         const bool hovered = widget->contains(mappedPos) &&
 440                              !widget->expansionToggleRect().contains(mappedPos) &&
 441                              !widget->selectionToggleRect().contains(mappedPos);
 442         if (hovered) {
 443             hoveredWidget = widget;
 444             break;
 445         }
 446     }
 447
 448     if (unhoveredWidget != hoveredWidget) {
 449         if (unhoveredWidget) {
 450             unhoveredWidget->setHovered(false);
 451             emit itemUnhovered(unhoveredWidget->index());
 452         }
 453
 454         if (hoveredWidget) {
 455             hoveredWidget->setHovered(true);
 456             emit itemHovered(hoveredWidget->index());
 457         }
 458     }
 459
 460     return false;
 461 }
 462
 463 bool KItemListController::hoverLeaveEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform)
 464 {
 465     Q_UNUSED(event);
 466     Q_UNUSED(transform);
 467
 468     if (!m_model || !m_view) {
 469         return false;
 470     }
 471
 472     foreach (KItemListWidget* widget, m_view->visibleItemListWidgets()) {
 473         if (widget->isHovered()) {
 474             widget->setHovered(false);
 475             emit itemUnhovered(widget->index());
 476         }
 477     }
 478     return false;
 479 }
 480
 481 bool KItemListController::wheelEvent(QGraphicsSceneWheelEvent* event, const QTransform& transform)
 482 {
 483     Q_UNUSED(event);
 484     Q_UNUSED(transform);
 485     return false;
 486 }
 487
 488 bool KItemListController::resizeEvent(QGraphicsSceneResizeEvent* event, const QTransform& transform)
 489 {
 490     Q_UNUSED(event);
 491     Q_UNUSED(transform);
 492     return false;
 493 }
 494
 495 bool KItemListController::processEvent(QEvent* event, const QTransform& transform)
 496 {
 497     if (!event) {
 498         return false;
 499     }
 500
 501     switch (event->type()) {
 502     case QEvent::KeyPress:
 503         return keyPressEvent(static_cast<QKeyEvent*>(event));
 504     case QEvent::InputMethod:
 505         return inputMethodEvent(static_cast<QInputMethodEvent*>(event));
 506     case QEvent::GraphicsSceneMousePress:
 507         return mousePressEvent(static_cast<QGraphicsSceneMouseEvent*>(event), QTransform());
 508     case QEvent::GraphicsSceneMouseMove:
 509         return mouseMoveEvent(static_cast<QGraphicsSceneMouseEvent*>(event), QTransform());
 510     case QEvent::GraphicsSceneMouseRelease:
 511         return mouseReleaseEvent(static_cast<QGraphicsSceneMouseEvent*>(event), QTransform());
 512     case QEvent::GraphicsSceneWheel:
 513          return wheelEvent(static_cast<QGraphicsSceneWheelEvent*>(event), QTransform());
 514     case QEvent::GraphicsSceneDragEnter:
 515         return dragEnterEvent(static_cast<QGraphicsSceneDragDropEvent*>(event), QTransform());
 516     case QEvent::GraphicsSceneDragLeave:
 517         return dragLeaveEvent(static_cast<QGraphicsSceneDragDropEvent*>(event), QTransform());
 518     case QEvent::GraphicsSceneDragMove:
 519         return dragMoveEvent(static_cast<QGraphicsSceneDragDropEvent*>(event), QTransform());
 520     case QEvent::GraphicsSceneDrop:
 521         return dropEvent(static_cast<QGraphicsSceneDragDropEvent*>(event), QTransform());
 522     case QEvent::GraphicsSceneHoverEnter:
 523         return hoverEnterEvent(static_cast<QGraphicsSceneHoverEvent*>(event), QTransform());
 524     case QEvent::GraphicsSceneHoverMove:
 525         return hoverMoveEvent(static_cast<QGraphicsSceneHoverEvent*>(event), QTransform());
 526     case QEvent::GraphicsSceneHoverLeave:
 527         return hoverLeaveEvent(static_cast<QGraphicsSceneHoverEvent*>(event), QTransform());
 528     case QEvent::GraphicsSceneResize:
 529         return resizeEvent(static_cast<QGraphicsSceneResizeEvent*>(event), transform);
 530     default:
 531         break;
 532     }
 533
 534     return false;
 535 }
 536
 537 void KItemListController::slotViewOffsetChanged(qreal current, qreal previous)
 538 {
 539     if (!m_view) {
 540         return;
 541     }
 542
 543     KItemListRubberBand* rubberBand = m_view->rubberBand();
 544     if (rubberBand->isActive()) {
 545         const qreal diff = current - previous;
 546         // TODO: Ideally just QCursor::pos() should be used as
 547         // new end-position but it seems there is no easy way
 548         // to have something like QWidget::mapFromGlobal() for QGraphicsWidget
 549         // (... or I just missed an easy way to do the mapping)
 550         QPointF endPos = rubberBand->endPosition();
 551         if (m_view->scrollOrientation() == Qt::Vertical) {
 552             endPos.ry() += diff;
 553         } else {
 554             endPos.rx() += diff;
 555         }
 556
 557         rubberBand->setEndPosition(endPos);
 558     }
 559 }
 560
 561 void KItemListController::slotRubberBandChanged()
 562 {
 563     if (!m_view || !m_model || m_model->count() <= 0) {
 564         return;
 565     }
 566
 567     const KItemListRubberBand* rubberBand = m_view->rubberBand();
 568     const QPointF startPos = rubberBand->startPosition();
 569     const QPointF endPos = rubberBand->endPosition();
 570     QRectF rubberBandRect = QRectF(startPos, endPos).normalized();
 571
 572     const bool scrollVertical = (m_view->scrollOrientation() == Qt::Vertical);
 573     if (scrollVertical) {
 574         rubberBandRect.translate(0, -m_view->offset());
 575     } else {
 576         rubberBandRect.translate(-m_view->offset(), 0);
 577     }
 578
 579     QSet<int> selectedItems;
 580
 581     // Select all visible items that intersect with the rubberband
 582     foreach (const KItemListWidget* widget, m_view->visibleItemListWidgets()) {
 583         const int index = widget->index();
 584
 585         const QRectF widgetRect = m_view->itemBoundingRect(index);
 586         if (widgetRect.intersects(rubberBandRect)) {
 587             const QRectF iconRect = widget->iconBoundingRect().translated(widgetRect.topLeft());
 588             const QRectF textRect = widget->textBoundingRect().translated(widgetRect.topLeft());
 589             if (iconRect.intersects(rubberBandRect) || textRect.intersects(rubberBandRect)) {
 590                 selectedItems.insert(index);
 591             }
 592         }
 593     }
 594
 595     // Select all invisible items that intersect with the rubberband. Instead of
 596     // iterating all items only the area which might be touched by the rubberband
 597     // will be checked.
 598     const bool increaseIndex = scrollVertical ?
 599                                startPos.y() > endPos.y(): startPos.x() > endPos.x();
 600
 601     int index = increaseIndex ? m_view->lastVisibleIndex() + 1 : m_view->firstVisibleIndex() - 1;
 602     bool selectionFinished = false;
 603     do {
 604         const QRectF widgetRect = m_view->itemBoundingRect(index);
 605         if (widgetRect.intersects(rubberBandRect)) {
 606             selectedItems.insert(index);
 607         }
 608
 609         if (increaseIndex) {
 610             ++index;
 611             selectionFinished = (index >= m_model->count()) ||
 612                                 ( scrollVertical && widgetRect.top()  > rubberBandRect.bottom()) ||
 613                                 (!scrollVertical && widgetRect.left() > rubberBandRect.right());
 614         } else {
 615             --index;
 616             selectionFinished = (index < 0) ||
 617                                 ( scrollVertical && widgetRect.bottom() < rubberBandRect.top()) ||
 618                                 (!scrollVertical && widgetRect.right()  < rubberBandRect.left());
 619         }
 620     } while (!selectionFinished);
 621
 622     m_selectionManager->setSelectedItems(selectedItems);
 623 }
 624
 625 #include "kitemlistcontroller.moc"