videoview: fade video overlay when mouse is not moving

Change-Id: I9095888304ba8290e6e9840b9b8bce4b2ba62028

videoview.cpp

@@ -59,6 +59,12 @@ VideoView::VideoView(QWidget* parent) :
     fadeAnim_->setEndValue(0);
     fadeAnim_->setEasingCurve(QEasingCurve::OutQuad);
  
+    // Setup the timer to start the fade when the mouse stops moving
+    this->setMouseTracking(true);
+    overlay_->setMouseTracking(true);
+    fadeTimer_.setSingleShot(true);
+    connect(&fadeTimer_, SIGNAL(timeout()), this, SLOT(fadeOverlayOut()));
+
     this->setContextMenuPolicy(Qt::CustomContextMenu);
     connect(this, SIGNAL(customContextMenuRequested(const QPoint&)),
         this, SLOT(showContextMenu(const QPoint&)));
@@ -119,14 +125,26 @@ void
 VideoView::enterEvent(QEvent* event)
 {
     Q_UNUSED(event)
-    fadeAnim_->stop();
-    fadeAnim_->targetObject()->setProperty(fadeAnim_->propertyName(), fadeAnim_->startValue());
+    showOverlay();
 }
 
 void
 VideoView::leaveEvent(QEvent* event)
 {
     Q_UNUSED(event)
+    fadeOverlayOut();
+}
+
+void
+VideoView::showOverlay()
+{
+    fadeAnim_->stop();
+    fadeAnim_->targetObject()->setProperty(fadeAnim_->propertyName(), fadeAnim_->startValue());
+}
+
+void
+VideoView::fadeOverlayOut()
+{
     if (not overlay_->isDialogVisible())
         fadeAnim_->start(QAbstractAnimation::KeepWhenStopped);
 }
@@ -333,6 +351,13 @@ VideoView::mouseReleaseEvent(QMouseEvent* event)
 void
 VideoView::mouseMoveEvent(QMouseEvent* event)
 {
+    // start/restart the timer after which the overlay will fade
+    if (fadeTimer_.isActive()) {
+        showOverlay();
+    } else {
+        fadeTimer_.start(startfadeOverlayTime_);
+    }
+ 
     QRect& previewRect =  ui->videoWidget->getPreviewRect();
     if (draggingPreview_) {
         if (previewRect.left() > 0

videoview.h

@@ -54,11 +54,14 @@ private slots:
     void updateCall();
     void showContextMenu(const QPoint& pos);
     void slotVideoStarted(Video::Renderer* renderer);
+    void fadeOverlayOut();
+    void showOverlay();
 
 private:
     Ui::VideoView* ui;
     VideoOverlay* overlay_;
     QPropertyAnimation* fadeAnim_;
+    QTimer fadeTimer_;
     QWidget* oldParent_;
     QSize oldSize_;
     QMetaObject::Connection timerConnection_;
@@ -72,6 +75,10 @@ private:
     constexpr static int resizeGrip_ = 40;
     constexpr static int minimalSize_ = 100;
 
+    // Time before the overlay starts fading out after the mouse stops
+    // moving within the videoview.
+    constexpr static int startfadeOverlayTime_ = 2000; //msec
+
     // TODO: fix when changing Qt version
     // Full(1.0) opacity bug affecting many Qt version (macOS + win10)
     // causing the render to take a buggy code path which can be avoided