basic button behavior

flatbutton.cpp

@@ -1,3 +1,6 @@
+#include <QDebug>
+#include <QStylePainter>
+#include <QStyleOptionButton>
 #include "flatbutton.h"
 
 FlatButton::FlatButton(QWidget *parent)
@@ -14,3 +17,44 @@ FlatButton::FlatButton(const QString &text, QWidget *parent)
 FlatButton::~FlatButton()
 {
 }
+
+void FlatButton::paintEvent(QPaintEvent *event)
+{
+    Q_UNUSED(event)
+
+    QStylePainter painter(this);
+
+    QStyleOptionButton option;
+    option.initFrom(this);
+    option.features = QStyleOptionButton::None;
+    option.features |= QStyleOptionButton::Flat;
+    if (isChecked())
+        option.state |= QStyle::State_On;
+    option.text = text();
+    option.icon = icon();
+    option.iconSize = iconSize();
+
+    painter.drawControl(QStyle::CE_PushButton, option);
+
+    if (underMouse()) {
+        QRect r = rect();
+        QBrush brush;
+        brush.setStyle(Qt::SolidPattern);
+        painter.setOpacity(0.1);
+        painter.fillRect(r, brush);
+    }
+}
+
+void FlatButton::enterEvent(QEvent *event)
+{
+    Q_UNUSED(event)
+
+    update();
+}
+
+void FlatButton::leaveEvent(QEvent *event)
+{
+    Q_UNUSED(event)
+
+    update();
+}

flatbutton.h

@@ -11,6 +11,11 @@ public:
     explicit FlatButton(QWidget *parent = 0);
     explicit FlatButton(const QString &text, QWidget *parent = 0);
     ~FlatButton();
+
+protected:
+    void paintEvent(QPaintEvent *event) Q_DECL_OVERRIDE;
+    void enterEvent(QEvent *event) Q_DECL_OVERRIDE;
+    void leaveEvent(QEvent *event) Q_DECL_OVERRIDE;
 };
 
 #endif // FLATBUTTON_H