QML Dynamic View Ordering Tutorial 2 - Dragging View Items▲

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Now that we have a visible list of items we want to be able to interact with them. We'll start by extending the delegate so the visible content can be dragged up and down the screen. The updated delegate looks like this:

 
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    Component {
        id: dragDelegate

        MouseArea {
            id: dragArea

            property bool held: false

            anchors { left: parent.left; right: parent.right }
            height: content.height

            drag.target: held ? content : undefined
            drag.axis: Drag.YAxis

            onPressAndHold: held = true
            onReleased: held = false

            Rectangle {
                id: content
                anchors {
                    horizontalCenter: parent.horizontalCenter
                    verticalCenter: parent.verticalCenter
                }
                width: dragArea.width; height: column.implicitHeight + 4

                border.width: 1
                border.color: "lightsteelblue"
                color: dragArea.held ? "lightsteelblue" : "white"
                Behavior on color { ColorAnimation { duration: 100 } }
                radius: 2
                states: State {
                    when: dragArea.held

                    ParentChange { target: content; parent: root }
                    AnchorChanges {
                        target: content
                        anchors { horizontalCenter: undefined; verticalCenter: undefined }
                    }
                }
                Column {
                    id: column
                    anchors { fill: parent; margins: 2 }

                    Text { text: 'Name: ' + name }
                    Text { text: 'Type: ' + type }
                    Text { text: 'Age: ' + age }
                    Text { text: 'Size: ' + size }
                }
            }
        }
    }

Walkthrough▲

The major change here is the root item of the delegate is now a MouseArea which provides handlers for mouse events and will allow us to drag the delegate's content item. It also acts as a container for the content item which is important as a delegate's root item is positioned by the view and cannot be moved by other means.

 
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        MouseArea {
            id