ToggleButton QML Size not used

Rectangle { width: Screen.desktopAvailableWidth/5; height: Screen.desktopAvailableWidth/5; color: "green" }

        ToggleButton {
                id: button1
                width: Screen.desktopAvailableWidth/5
                height: Screen.desktopAvailableWidth/5
                Image {
                    anchors.centerIn: parent
                    width: parent.width * 0.7
                    height: parent.height * 0.7
                    source: "qrc:/images/test.png"
                }
            }