After all this time, I don't fin a way to do it properly.

I'm using QML and it's fine now. For people intereested in, this is my QML component:

import QtQuick 2.5
import QtQuick.Controls 1.4
import QtQuick.Controls.Styles 1.4

Button
{
property color backgroundColor
property alias tooltip : buttonAction.tooltip
property string imageSource
signal buttonClicked ( )

action : buttonAction activeFocusOnPress : true Keys.onPressed : { if ( (event.key == Qt.Key_Return||event.key == Qt.Key_Enter) && activeFocus) { buttonClicked ( ); event.accepted = true; } } style : ButtonStyle { background: Rectangle { id : backgroundRectangle color : backgroundColor Rectangle { id : roundedRectangle color : control.pressed?Qt.darker(backgroundColor, 1.1):backgroundColor anchors.fill : parent radius : 10 scale : ( control.hovered||control.activeFocus )?1:0.9 Image { id : buttonImage anchors.fill: parent fillMode : Image.PreserveAspectFit source : imageSource } } } } Action { id : buttonAction onTriggered : buttonClicked () }

}