Qt Quick Examples - Drag and Drop

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import QtQuick 2.12
import QtQml.Models 2.1

GridView {
    id: root
    width: 320; height: 480
    cellWidth: 80; cellHeight: 80

    displaced: Transition {
        NumberAnimation { properties: "x,y"; easing.type: Easing.OutQuad }
    }

    model: DelegateModel {
        id: visualModel
        model: ListModel {
            id: colorModel
            ListElement { color: "blue" }
            ListElement { color: "green" }
            ListElement { color: "red" }
            ListElement { color: "yellow" }
            ListElement { color: "orange" }
            ListElement { color: "purple" }
            ListElement { color: "cyan" }
            ListElement { color: "magenta" }
            ListElement { color: "chartreuse" }
            ListElement { color: "aquamarine" }
            ListElement { color: "indigo" }
            ListElement { color: "black" }
            ListElement { color: "lightsteelblue" }
            ListElement { color: "violet" }
            ListElement { color: "grey" }
            ListElement { color: "springgreen" }
            ListElement { color: "salmon" }
            ListElement { color: "blanchedalmond" }
            ListElement { color: "forestgreen" }
            ListElement { color: "pink" }
            ListElement { color: "navy" }
            ListElement { color: "goldenrod" }
            ListElement { color: "crimson" }
            ListElement { color: "teal" }
        }
        delegate: DropArea {
            id: delegateRoot

            width: 80; height: 80

            onEntered: visualModel.items.move(drag.source.visualIndex, icon.visualIndex)
            property int visualIndex: DelegateModel.itemsIndex
            Binding { target: icon; property: "visualIndex"; value: visualIndex }

            Rectangle {
                id: icon
                property int visualIndex: 0
                width: 72; height: 72
                anchors {
                    horizontalCenter: parent.horizontalCenter;
                    verticalCenter: parent.verticalCenter
                }
                radius: 3
                color: model.color

                Text {
                    anchors.centerIn: parent
                    color: "white"
                    text: parent.visualIndex
                }

                DragHandler {
                    id: dragHandler
                }

                Drag.active: dragHandler.active
                Drag.source: icon
                Drag.hotSpot.x: 36
                Drag.hotSpot.y: 36

                states: [
                    State {
                        when: icon.Drag.active
                        ParentChange {
                            target: icon
                            parent: root
                        }

                        AnchorChanges {
                            target: icon
                            anchors.horizontalCenter: undefined
                            anchors.verticalCenter: undefined
                        }
                    }
                ]
            }
        }
    }
}