- Qt 5.5
- Qt Quick
- QML Dynamic View Ordering Tutorial 4 - Sorting Items
- dynamicview.qml Example File
- Qt 5.5.1 Reference Documentation

# dynamicview.qml Example File

tutorials/dynamicview/dynamicview4/dynamicview.qml

    /****************************************************************************
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    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
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    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
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    import QtQuick 2.0
    import QtQml.Models 2.1

    Rectangle {
        id: root

        width: 300; height: 400

        Component {
            id: dragDelegate

            MouseArea {
                id: dragArea

                property bool held: false

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

                enabled: visualModel.sortOrder == visualModel.lessThan.length

                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

                    Drag.active: dragArea.held
                    Drag.source: dragArea
                    Drag.hotSpot.x: width / 2
                    Drag.hotSpot.y: height / 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 }
                    }
                }

                DropArea {
                    anchors { fill: parent; margins: 10 }

                    onEntered: {
                        visualModel.items.move(
                                drag.source.DelegateModel.itemsIndex,
                                dragArea.DelegateModel.itemsIndex)
                    }
                }
            }
        }
        DelegateModel {
            id: visualModel
            property var lessThan: [
                function(left, right) { return left.name < right.name },
                function(left, right) { return left.type < right.type },
                function(left, right) { return left.age < right.age },
                function(left, right) {
                    if (left.size == "Small")
                        return true
                    else if (right.size == "Small")
                        return false
                    else if (left.size == "Medium")
                        return true
                    else
                        return false
                }
            ]

            property int sortOrder: orderSelector.selectedIndex
            onSortOrderChanged: items.setGroups(0, items.count, "unsorted")

            function insertPosition(lessThan, item) {
                var lower = 0
                var upper = items.count
                while (lower < upper) {
                    var middle = Math.floor(lower + (upper - lower) / 2)
                    var result = lessThan(item.model, items.get(middle).model);
                    if (result) {
                        upper = middle
                    } else {
                        lower = middle + 1
                    }
                }
                return lower
            }

            function sort(lessThan) {
                while (unsortedItems.count > 0) {
                    var item = unsortedItems.get(0)
                    var index = insertPosition(lessThan, item)

                    item.groups = "items"
                    items.move(item.itemsIndex, index)
                }
            }

            items.includeByDefault: false
            groups: VisualDataGroup {
                id: unsortedItems
                name: "unsorted"

                includeByDefault: true
                onChanged: {
                    if (visualModel.sortOrder == visualModel.lessThan.length)
                        setGroups(0, count, "items")
                    else
                        visualModel.sort(visualModel.lessThan[visualModel.sortOrder])
                }
            }
            model: PetsModel {}
            delegate: dragDelegate
        }
        ListView {
            id: view

            anchors {
                left: parent.left; top: parent.top; right: parent.right; bottom: orderSelector.top;
                margins: 2
            }

            model: visualModel

            spacing: 4
            cacheBuffer: 50
        }

        ListSelector {
            id: orderSelector

            anchors { left: parent.left; right: parent.right; bottom: parent.bottom; margins: 2 }

            label: "Sort By"
            list: [ "Name", "Type", "Age", "Size", "Custom" ]
        }
    }