Qt Quick Demo - Photo Viewer

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 import QtQuick 2.0

 Flipable {
     id: flipable

     property alias frontLabel: frontButton.label
     property alias backLabel: backButton.label

     property int angle: 0
     property int randomAngle: Math.random() * (2 * 6 + 1) - 6
     property bool flipped: false

     signal frontClicked
     signal backClicked
     signal tagChanged(string tag)

     front: EditableButton {
         id: frontButton; rotation: flipable.randomAngle
         anchors { centerIn: parent; verticalCenterOffset: -20 }
         onClicked: flipable.frontClicked()
         onLabelChanged: flipable.tagChanged(label)
     }

     back: Button {
         id: backButton; tint: "red"; rotation: flipable.randomAngle
         anchors { centerIn: parent; verticalCenterOffset: -20 }
         onClicked: flipable.backClicked()
     }

     transform: Rotation {
         origin.x: flipable.width / 2; origin.y: flipable.height / 2
         axis.x: 0; axis.y: 1; axis.z: 0
         angle: flipable.angle
     }

     states: State {
         name: "back"; when: flipable.flipped
         PropertyChanges { target: flipable; angle: 180 }
     }

     transitions: Transition {
         ParallelAnimation {
             NumberAnimation { properties: "angle"; duration: 400 }
             SequentialAnimation {
                 NumberAnimation { target: flipable; property: "scale"; to: 0.8; duration: 200 }
                 NumberAnimation { target: flipable; property: "scale"; to: 1.0; duration: 200 }
             }
         }
     }
 }