animate halo

components/slider.cpp

@@ -1,5 +1,6 @@
 #include "slider.h"
 #include <QPainter>
+#include <QPropertyAnimation>
 #include <QStringBuilder>
 #include <QMouseEvent>
 #include <QDebug>
@@ -10,6 +11,33 @@ Slider::Slider(QWidget *parent)
     : QAbstractSlider(parent),
       d_ptr(new SliderPrivate(this))
 {
+    QPropertyAnimation *animation;
+
+    animation = new QPropertyAnimation;
+
+    animation->setPropertyName("haloScaleFactor");
+    animation->setTargetObject(this);
+    animation->setStartValue(0.8);
+    animation->setEndValue(1);
+    animation->setDuration(900);
+    animation->setEasingCurve(QEasingCurve::InOutQuad);
+
+    d_ptr->haloAnimation->addAnimation(animation);
+
+    animation = new QPropertyAnimation;
+
+    animation->setPropertyName("haloScaleFactor");
+    animation->setTargetObject(this);
+    animation->setStartValue(1);
+    animation->setEndValue(0.8);
+    animation->setDuration(900);
+    animation->setEasingCurve(QEasingCurve::InOutQuad);
+
+    d_ptr->haloAnimation->addAnimation(animation);
+
+    d_ptr->haloAnimation->setLoopCount(-1);
+    d_ptr->haloAnimation->start();
+
     connect(this, SIGNAL(actionTriggered(int)), this, SLOT(handleAction(int)));
 }
 
@@ -17,6 +45,21 @@ Slider::~Slider()
 {
 }
 
+void Slider::setHaloScaleFactor(qreal factor)
+{
+    Q_D(Slider);
+
+    d->haloScaleFactor = factor;
+    update();
+}
+
+qreal Slider::haloScaleFactor() const
+{
+    Q_D(const Slider);
+
+    return d->haloScaleFactor;
+}
+
 void Slider::handleAction(int action)
 {
     Q_D(Slider);

components/slider.h

@@ -10,10 +10,15 @@ class Slider : public QAbstractSlider
 {
     Q_OBJECT
 
+    Q_PROPERTY(qreal haloScaleFactor WRITE setHaloScaleFactor READ haloScaleFactor)
+
 public:
     explicit Slider(QWidget *parent = 0);
     ~Slider();
 
+    void setHaloScaleFactor(qreal factor);
+    qreal haloScaleFactor() const;
+
 protected slots:
     void handleAction(int action);
 

components/slider_p.h

@@ -3,6 +3,7 @@
 
 #include "slider.h"
 #include <QPainter>
+#include <QSequentialAnimationGroup>
 #include "lib/style.h"
 
 #define THUMB_OUTER_SIZE 35
@@ -15,6 +16,8 @@ class SliderPrivate
 public:
     SliderPrivate(Slider *parent)
         : q_ptr(parent),
+          haloAnimation(new QSequentialAnimationGroup(parent)),
+          haloScaleFactor(1),
           hoverTrack(false),
           hoverThumb(false),
           step(false),
@@ -90,7 +93,9 @@ public:
 
         painter->setRenderHint(QPainter::Antialiasing);
 
-        QRectF halo(0, 0, THUMB_OUTER_SIZE, THUMB_OUTER_SIZE);
+        qreal size = THUMB_OUTER_SIZE * haloScaleFactor;
+
+        QRectF halo(0, 0, size, size);
         halo.moveCenter(thumbGeometry().center());
 
         painter->drawEllipse(halo);
@@ -148,10 +153,12 @@ public:
 
     Slider *const q_ptr;
 
-    bool hoverTrack;
-    bool hoverThumb;
-    bool step;
-    int  stepTo;
+    QSequentialAnimationGroup *const haloAnimation;
+    qreal haloScaleFactor;
+    bool  hoverTrack;
+    bool  hoverThumb;
+    bool  step;
+    int   stepTo;
 };
 
 #endif // SLIDER_P_H