Merge pull request #5042 from narunlifescience/master

volume slider handle glow effect using system theme

src/widgets/sliderwidget.cpp

@@ -195,32 +195,14 @@ Amarok::VolumeSlider::VolumeSlider(QWidget* parent, uint max)
     : Amarok::Slider(Qt::Horizontal, parent, max),
       m_animCount(0),
       m_animTimer(new QTimer(this)),
-      m_pixmapInset(QPixmap(volumePixmapDraw ())) {
+      m_pixmapInset(QPixmap(drawVolumePixmap ())) {
   setFocusPolicy(Qt::NoFocus);
 
-  // Store window text color to check theme change at paintEvent
+  // Store theme colors to check theme change at paintEvent
   m_previous_theme_text_color = palette().color(QPalette::WindowText);
+  m_previous_theme_highlight_color = palette().color(QPalette::Highlight);
 
-  // BEGIN Calculate handle animation pixmaps for mouse-over effect
+  drawVolumeSliderHandle();
-  QImage pixmapHandle(":volumeslider-handle.png");
-  QImage pixmapHandleGlow(":volumeslider-handle_glow.png");
-
-  float opacity = 0.0;
-  const float step = 1.0 / ANIM_MAX;
-  QImage dst;
-  for (int i = 0; i < ANIM_MAX; ++i) {
-    dst = pixmapHandle.copy();
-
-    QPainter p(&dst);
-    p.setOpacity(opacity);
-    p.drawImage(0, 0, pixmapHandleGlow);
-    p.end();
-
-    m_handlePixmaps.append(QPixmap::fromImage(dst));
-    opacity += step;
-  }
-  // END
-
   generateGradient();
 
   setMinimumWidth(m_pixmapInset.width());
@@ -306,10 +288,15 @@ void Amarok::VolumeSlider::paintEvent(QPaintEvent*) {
 
   // If theme changed since last paintEvent, redraw the volume pixmap with new theme colors 
   if (m_previous_theme_text_color != palette().color(QPalette::WindowText)) {
-    m_pixmapInset = volumePixmapDraw();
+    m_pixmapInset = drawVolumePixmap();
     m_previous_theme_text_color = palette().color(QPalette::WindowText);
   }
 
+  if (m_previous_theme_highlight_color != palette().color(QPalette::Highlight)) {
+    drawVolumeSliderHandle();
+    m_previous_theme_highlight_color = palette().color(QPalette::Highlight);
+  }
+
   p.drawPixmap(0, 0, m_pixmapGradient, 0, 0, offset + padding, 0);
   p.drawPixmap(0, 0, m_pixmapInset);
   p.drawPixmap(offset - m_handlePixmaps[0].width() / 2 + padding, 0,
@@ -345,7 +332,7 @@ void Amarok::VolumeSlider::paletteChange(const QPalette&) {
   generateGradient();
 }
 
-QPixmap Amarok::VolumeSlider::volumePixmapDraw () const {
+QPixmap Amarok::VolumeSlider::drawVolumePixmap () const {
   QPixmap pixmap(112, 36);
   pixmap.fill(Qt::transparent);
   QPainter painter(&pixmap);
@@ -366,3 +353,41 @@ QPixmap Amarok::VolumeSlider::volumePixmapDraw () const {
   // Return QPixmap
   return pixmap;
 }
+
+void Amarok::VolumeSlider::drawVolumeSliderHandle() {
+  QImage pixmapHandle(":volumeslider-handle.png");
+  QImage pixmapHandleGlow(":/volumeslider-handle_glow.png");
+
+  QImage pixmapHandleGlow_image(pixmapHandleGlow.size(), QImage::Format_ARGB32_Premultiplied);
+  QPainter painter(&pixmapHandleGlow_image);
+  
+  painter.setRenderHint(QPainter::Antialiasing);
+  painter.setRenderHint(QPainter::SmoothPixmapTransform);
+
+  // repaint volume slider handle glow image with theme highlight color
+  painter.fillRect(pixmapHandleGlow_image.rect(), QBrush(palette().color(QPalette::Highlight)));
+  painter.setCompositionMode(QPainter::CompositionMode_DestinationIn);
+  painter.drawImage(0, 0, pixmapHandleGlow);
+  
+  // Overlay the volume slider handle image 
+  painter.setCompositionMode(QPainter::CompositionMode_SourceAtop);
+  painter.drawImage(0, 0, pixmapHandle);
+
+  // BEGIN Calculate handle animation pixmaps for mouse-over effect
+  float opacity = 0.0;
+  const float step = 1.0 / ANIM_MAX;
+  QImage dst;
+  m_handlePixmaps.clear();
+  for (int i = 0; i < ANIM_MAX; ++i) {
+    dst = pixmapHandle.copy();
+
+    QPainter p(&dst);
+    p.setOpacity(opacity);
+    p.drawImage(0, 0, pixmapHandleGlow_image);
+    p.end();
+
+    m_handlePixmaps.append(QPixmap::fromImage(dst));
+    opacity += step;
+  }
+  // END
+}

src/widgets/sliderwidget.h

@@ -98,7 +98,6 @@ class VolumeSlider : public Slider {
 
  public:
   VolumeSlider(QWidget* parent, uint max = 0);
-  QPixmap volumePixmapDraw() const;
 
  protected:
   virtual void paintEvent(QPaintEvent*);
@@ -115,6 +114,8 @@ class VolumeSlider : public Slider {
 
  private:
   void generateGradient();
+  QPixmap drawVolumePixmap() const;
+  void drawVolumeSliderHandle();
 
   VolumeSlider(const VolumeSlider&);             // undefined
   VolumeSlider& operator=(const VolumeSlider&);  // undefined
@@ -131,6 +132,7 @@ class VolumeSlider : public Slider {
   QPixmap m_pixmapGradient;
 
   QColor m_previous_theme_text_color;
+  QColor m_previous_theme_highlight_color;
 
   QList<QPixmap> m_handlePixmaps;
 };