QQuickTableView: support multi-selection

Implement support for doing multiple selections in
TableView by holding down the shift modifier while
dragging.

[ChangeLog][Quick][TableView] Added multi-selection support
if using a SelectionRectangle and holding down the shift-modifier.

Change-Id: Ife622aeea2ed60a5741df01f3aac2fb647108aa9
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

src/quick/items/qquickselectable_p.h

@@ -25,7 +25,7 @@ class Q_QUICK_PRIVATE_EXPORT QQuickSelectable
 public:
     virtual QQuickItem *selectionPointerHandlerTarget() const = 0;
 
-    virtual bool canStartSelection(const QPointF &pos) = 0;
+    virtual bool startSelection(const QPointF &pos) = 0;
     virtual void setSelectionStartPos(const QPointF &pos) = 0;
     virtual void setSelectionEndPos(const QPointF &pos) = 0;
     virtual void clearSelection() = 0;

src/quick/items/qquicktableview.cpp

@@ -1517,11 +1517,18 @@ QQuickItem *QQuickTableViewPrivate::selectionPointerHandlerTarget() const
     return const_cast<QQuickTableView *>(q_func())->contentItem();
 }
 
-bool QQuickTableViewPrivate::canStartSelection(const QPointF &pos)
+bool QQuickTableViewPrivate::startSelection(const QPointF &pos)
 {
+    Q_Q(QQuickTableView);
     Q_UNUSED(pos);
     // Only allow a selection if it doesn't conflict with resizing
-    return resizeHandler->state() == QQuickTableViewResizeHandler::Listening;
+    const bool canStartSelection = resizeHandler->state() == QQuickTableViewResizeHandler::Listening;
+    if (canStartSelection) {
+        selectionStartCell = QPoint(-1, -1);
+        selectionEndCell = QPoint(-1, -1);
+        q->closeEditor();
+    }
+    return canStartSelection;
 }
 
 void QQuickTableViewPrivate::setSelectionStartPos(const QPointF &pos)
@@ -4633,12 +4640,12 @@ void QQuickTableViewPrivate::init()
         positionYAnimation.stop();
 
         if (!q->isInteractive())
-            handleTap(tapHandler->point().pressPosition());
+            handleTap(tapHandler->point());
     });
 
     QObject::connect(tapHandler, &QQuickTapHandler::singleTapped, [this, q, tapHandler] {
         if (q->isInteractive())
-            handleTap(tapHandler->point().pressPosition());
+            handleTap(tapHandler->point());
     });
 
     QObject::connect(tapHandler, &QQuickTapHandler::doubleTapped, [this, q, tapHandler] {
@@ -4660,13 +4667,15 @@ void QQuickTableViewPrivate::init()
     });
 }
 
-void QQuickTableViewPrivate::handleTap(const QPointF &pos)
+void QQuickTableViewPrivate::handleTap(const QQuickHandlerPoint &point)
 {
     Q_Q(QQuickTableView);
 
     if (keyNavigationEnabled)
         q->forceActiveFocus(Qt::MouseFocusReason);
 
+    if (point.modifiers() != Qt::NoModifier)
+        return;
     if (resizableRows && hoverHandler->m_row != -1)
         return;
     if (resizableColumns && hoverHandler->m_column != -1)
@@ -4679,14 +4688,14 @@ void QQuickTableViewPrivate::handleTap(const QPointF &pos)
         prevIndex = selectionModel->currentIndex();
         if (pointerNavigationEnabled) {
             clearSelection();
-            setCurrentIndexFromTap(pos);
+            setCurrentIndexFromTap(point.position());
         }
     }
 
     if (editTriggers != QQuickTableView::NoEditTriggers)
         q->closeEditor();
 
-    const QModelIndex tappedIndex = q->modelIndex(q->cellAtPosition(pos));
+    const QModelIndex tappedIndex = q->modelIndex(q->cellAtPosition(point.position()));
     if (canEdit(tappedIndex, false)) {
         if (editTriggers & QQuickTableView::SingleTapped)
             q->edit(tappedIndex);

src/quick/items/qquicktableview_p_p.h

@@ -548,7 +548,7 @@ public:
                              int serializedModelIndex,
                              QObject *object, bool init);
 
-    void handleTap(const QPointF &pos);
+    void handleTap(const QQuickHandlerPoint &point);
     void setCurrentIndexFromTap(const QPointF &pos);
     void setCurrentIndex(const QPoint &cell);
     bool setCurrentIndexFromKeyEvent(QKeyEvent *e);
@@ -557,7 +557,7 @@ public:
 
     // QQuickSelectable
     QQuickItem *selectionPointerHandlerTarget() const override;
-    bool canStartSelection(const QPointF &pos) override;
+    bool startSelection(const QPointF &pos) override;
     void setSelectionStartPos(const QPointF &pos) override;
     void setSelectionEndPos(const QPointF &pos) override;
     void clearSelection() override;

src/quicktemplates/qquickselectionrectangle.cpp

@@ -182,7 +182,9 @@ QQuickSelectionRectanglePrivate::QQuickSelectionRectanglePrivate()
 
     QObject::connect(m_tapHandler, &QQuickTapHandler::longPressed, [this]() {
         const QPointF pos = m_tapHandler->point().pressPosition();
-        if (!m_selectable->canStartSelection(pos))
+        const auto modifiers = m_tapHandler->point().modifiers();
+
+        if (!m_selectable->startSelection(pos))
             return;
         if (handleUnderPos(pos) != nullptr) {
             // Don't allow press'n'hold to start a new
@@ -199,6 +201,7 @@ QQuickSelectionRectanglePrivate::QQuickSelectionRectanglePrivate()
             }
         }
 
+        if (!modifiers.testFlag(Qt::ShiftModifier))
             m_selectable->clearSelection();
         m_selectable->setSelectionStartPos(pos);
         m_selectable->setSelectionEndPos(pos);
@@ -209,10 +212,12 @@ QQuickSelectionRectanglePrivate::QQuickSelectionRectanglePrivate()
     QObject::connect(m_dragHandler, &QQuickDragHandler::activeChanged, [this]() {
         const QPointF startPos = m_dragHandler->centroid().pressPosition();
         const QPointF dragPos = m_dragHandler->centroid().position();
+        const auto modifiers = m_dragHandler->centroid().modifiers();
 
         if (m_dragHandler->active()) {
-            if (!m_selectable->canStartSelection(startPos))
+            if (!m_selectable->startSelection(startPos))
                 return;
+            if (!modifiers.testFlag(Qt::ShiftModifier))
                 m_selectable->clearSelection();
             m_selectable->setSelectionStartPos(startPos);
             m_selectable->setSelectionEndPos(dragPos);

tests/auto/quickcontrols/controls/data/tst_selectionrectangle.qml

@@ -198,8 +198,36 @@ TestCase {
         mousePress(tableView, 1, 1, Qt.LeftButton)
         mousePress(tableView, 1, 1, Qt.LeftButton, Qt.NoModifier, 1000)
         verify(!tableView.selectionModel.hasSelection)
+
     }
 
+// TODO: enable this test when mouseDrag sends modifiers for all mouse events
+// (including mouseMove)
+//    function test_multi_selection() {
+//        let tableView = createTemporaryObject(tableviewComp, testCase)
+//        verify(tableView)
+//        let selectionRectangle = tableView.selectionRectangle
+//        verify(selectionRectangle)
+//        verify(!tableView.selectionModel.hasSelection)
+
+//        selectionRectangle.selectionMode = SelectionRectangle.Drag
+
+//        mouseDrag(tableView, 1, 1, (cellWidth * 2) - 2, 1, Qt.LeftButton)
+//        verify(tableView.selectionModel.hasSelection)
+//        compare(tableView.selectionModel.selectedIndexes.length, 2)
+//        verify(tableView.selectionModel.isSelected(tableView.model.index(0, 0)))
+//        verify(tableView.selectionModel.isSelected(tableView.model.index(0, 1)))
+
+//        // Hold down shift, and drag again to do a multi-selection
+//        mouseDrag(tableView, 1, cellHeight + 5, (cellWidth * 2) - 2, 1, Qt.LeftButton, Qt.ShiftModifier)
+//        verify(tableView.selectionModel.hasSelection)
+//        compare(tableView.selectionModel.selectedIndexes.length, 4)
+//        verify(tableView.selectionModel.isSelected(tableView.model.index(0, 0)))
+//        verify(tableView.selectionModel.isSelected(tableView.model.index(0, 1)))
+//        verify(tableView.selectionModel.isSelected(tableView.model.index(1, 0)))
+//        verify(tableView.selectionModel.isSelected(tableView.model.index(1, 1)))
+//    }
+
     function test_pressAndHold_data() {
         return [
             { tag: "resize enabled", resizeEnabled: true },