Some timeline visual updates and corrections

- Selection rect selects keyframes based on center point rather than
the whole keyframe.
- Make playhead vertical line extend to the whole height of the
timeline widget.
- Prevent a jump when dragging a selection of keyframes.
- Prevent dragging keyframes if the clicked keyframe is deselected
(i.e. Ctrl+click a selected keyframe).
- Correct timeline bounds checking while dragging multiple keyframes.

Task-number: QDS-1073
Change-Id: Ibf118ecccfe86346f2d4e921c0958294a15c24f1
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

src/plugins/qmldesigner/components/timelineeditor/timelinegraphicsscene.cpp

@@ -112,7 +112,7 @@ TimelineGraphicsScene::TimelineGraphicsScene(TimelineWidget *parent)
         if (auto *rview = rulerView())
             rview->setSceneRect(rect);
 
-        m_currentFrameIndicator->setHeight(m_layout->geometry().height());
+        m_currentFrameIndicator->setHeight(9999); // big enough number (> timeline widget height)
     });
 
     auto moveFrameIndicator = [this](const QPointF &pos) {

src/plugins/qmldesigner/components/timelineeditor/timelinemovetool.cpp

@@ -68,7 +68,12 @@ void TimelineMoveTool::mousePressEvent(TimelineMovableAbstractItem *item,
                                        QGraphicsSceneMouseEvent *event)
 {
     Q_UNUSED(item)
-    Q_UNUSED(event)
+
+    if (auto *current = currentItem()->asTimelineKeyframeItem()) {
+        const qreal sourceFrame = qRound(current->mapFromSceneToFrame(current->rect().center().x()));
+        const qreal targetFrame = qRound(current->mapFromSceneToFrame(event->scenePos().x()));
+        m_pressKeyframeDelta = targetFrame - sourceFrame;
+    }
 }
 
 void TimelineMoveTool::mouseMoveEvent(TimelineMovableAbstractItem *item,
@@ -80,34 +85,34 @@ void TimelineMoveTool::mouseMoveEvent(TimelineMovableAbstractItem *item,
         return;
 
     if (auto *current = currentItem()->asTimelineKeyframeItem()) {
+        // prevent dragging if deselecting a keyframe (Ctrl+click and drag a selected keyframe)
+        if (!current->highlighted())
+            return;
+
         const qreal sourceFrame = qRound(current->mapFromSceneToFrame(current->rect().center().x()));
         const qreal targetFrame = qRound(current->mapFromSceneToFrame(event->scenePos().x()));
-        qreal deltaFrame = targetFrame - sourceFrame;
+        qreal deltaFrame = targetFrame - sourceFrame - m_pressKeyframeDelta;
 
         const qreal minFrame = scene()->startFrame();
         const qreal maxFrame = scene()->endFrame();
 
-        auto bbox = scene()->selectionBounds().united(current->rect());
+        auto bbox = scene()->selectionBounds().adjusted(TimelineConstants::keyFrameSize / 2, 0,
+                                                        -TimelineConstants::keyFrameSize / 2, 0);
+        double firstFrame = std::round(current->mapFromSceneToFrame(bbox.left()));
+        double lastFrame = std::round(current->mapFromSceneToFrame(bbox.right()));
 
-        double firstFrame = std::round(current->mapFromSceneToFrame(bbox.center().x()));
-        double lastFrame = std::round(current->mapFromSceneToFrame(bbox.center().x()));
-
-        if ((lastFrame + deltaFrame) > maxFrame)
+        if (lastFrame + deltaFrame > maxFrame)
             deltaFrame = maxFrame - lastFrame;
-
-        if ((firstFrame + deltaFrame) <= minFrame)
+        else if (firstFrame + deltaFrame < minFrame)
             deltaFrame = minFrame - firstFrame;
 
-        current->setPosition(sourceFrame + deltaFrame);
-
         scene()->statusBarMessageChanged(tr(TimelineConstants::statusBarKeyframe)
                                          .arg(sourceFrame + deltaFrame));
 
-        for (auto *keyframe : scene()->selectedKeyframes()) {
-            if (keyframe != current) {
-                qreal pos = std::round(current->mapFromSceneToFrame(keyframe->rect().center().x()));
-                keyframe->setPosition(pos + deltaFrame);
-            }
+        const QList<TimelineKeyframeItem *> selectedKeyframes = scene()->selectedKeyframes();
+        for (auto *keyframe : selectedKeyframes) {
+            qreal pos = std::round(keyframe->mapFromSceneToFrame(keyframe->rect().center().x()));
+            keyframe->setPosition(pos + deltaFrame);
         }
 
     } else {

src/plugins/qmldesigner/components/timelineeditor/timelinemovetool.h

@@ -52,6 +52,9 @@ public:
 
     void keyPressEvent(QKeyEvent *keyEvent) override;
     void keyReleaseEvent(QKeyEvent *keyEvent) override;
+
+private:
+    qreal m_pressKeyframeDelta = 0.;
 };
 
 } // namespace QmlDesigner

src/plugins/qmldesigner/components/timelineeditor/timelinepropertyitem.cpp

@@ -517,10 +517,10 @@ void TimelineKeyframeItem::updateFrame()
     setPosition(m_frame.variantProperty("frame").value().toReal());
 }
 
-void TimelineKeyframeItem::setPosition(qreal position)
+void TimelineKeyframeItem::setPosition(qreal frame)
 {
     int offset = (TimelineConstants::sectionHeight - TimelineConstants::keyFrameSize) / 2;
-    const qreal scenePostion = mapFromFrameToScene(position);
+    const qreal scenePostion = mapFromFrameToScene(frame);
 
     setRect(scenePostion - TimelineConstants::keyFrameSize / 2,
             offset,
@@ -622,6 +622,11 @@ void TimelineKeyframeItem::setHighlighted(bool b)
     update();
 }
 
+bool TimelineKeyframeItem::highlighted() const
+{
+    return m_highlight;
+}
+
 TimelinePropertyItem *TimelineKeyframeItem::propertyItem() const
 {
     /* The parentItem is always a TimelinePropertyItem. See constructor */

src/plugins/qmldesigner/components/timelineeditor/timelinepropertyitem.h

@@ -58,8 +58,9 @@ public:
     void updateFrame();
 
     void setHighlighted(bool b);
+    bool highlighted() const;
 
-    void setPosition(qreal position);
+    void setPosition(qreal frame);
 
     void commitPosition(const QPointF &point) override;
 

src/plugins/qmldesigner/components/timelineeditor/timelineselectiontool.cpp

@@ -98,7 +98,7 @@ void TimelineSelectionTool::mouseMoveEvent(TimelineMovableAbstractItem *item,
         m_selectionRect->show();
 
         aboutToSelect(selectionMode(event),
-                      scene()->items(m_selectionRect->rect(), Qt::ContainsItemShape));
+                      scene()->items(m_selectionRect->rect(), Qt::IntersectsItemBoundingRect));
     }
 }
 
@@ -164,6 +164,10 @@ void TimelineSelectionTool::aboutToSelect(SelectionMode mode, QList<QGraphicsIte
 
     for (auto *item : items) {
         if (auto *keyframe = TimelineMovableAbstractItem::asTimelineKeyframeItem(item)) {
+            // if keyframe's center isn't inside m_selectionRect, discard it
+            if (!m_selectionRect->rect().contains(keyframe->rect().center() + item->scenePos()))
+                continue;
+
             if (mode == SelectionMode::Remove)
                 keyframe->setHighlighted(false);
             else if (mode == SelectionMode::Toggle)