qzxing/examples/QMLBarcodeScanner/FlickableList.qml

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import Qt 4.7

Item {
    id: flickableList
    clip: true

    signal clicked

    property alias delegate : repeater.delegate

    property variant items: []
    property int index: 0
    property int itemWidth : flickableList.width

    function scrollTo(id) {
        var x = id*flickableList.itemWidth
        if (flickArea.contentX != x) {
            centeringAnimation.stop();
            flickArea.newX = id*flickableList.itemWidth
            centeringAnimation.start();
        }
    }

    onIndexChanged: scrollTo(index)
    onWidthChanged: scrollTo(index)

    Flickable {
        id: flickArea
        property int newX: 0

        MouseArea {
            anchors.fill: parent
            onClicked: {
                var x = mapToItem(flickableList, mouseX, mouseY).x

                if (x < flickableList.width/3) {
                    if (flickableList.index > 0)
                        flickableList.scrollTo(flickableList.index-1);
                } else if (x > flickableList.width*2/3) {
                    if (flickableList.index < flickableList.items.length-1)
                        flickableList.scrollTo(flickableList.index+1);
                } else {
                    flickableList.clicked()
                }

            }
        }

        PropertyAnimation {
            id: centeringAnimation
            target: flickArea
            properties: "contentX"
            easing.type: Easing.OutQuad
            from: flickArea.contentX
            to: flickArea.newX

            onCompleted: {
                flickableList.index = flickArea.newX / flickableList.itemWidth
            }
        }

        onMovementStarted: {
            centeringAnimation.stop();
        }

        onMovementEnded: {
            var modulo = flickArea.contentX % flickableList.itemWidth;
            var offset = flickableList.itemWidth / 2;
            flickArea.newX = modulo < offset ? flickArea.contentX - modulo : flickArea.contentX + (flickableList.itemWidth - modulo);
            centeringAnimation.start();
        }


        width: flickableList.width
        height: flickableList.height
        contentWidth: items.width
        contentHeight: items.height
        flickDeceleration: 4000

        Row {
            id: items
            Repeater {
                id: repeater
                model: flickableList.items.length
            }
        }
    }
}