dynamicview.qml Example File | Qt Quick 5.12.12

- Qt 5.12
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- QML Dynamic View Ordering Tutorial 4 - Sorting Items
- dynamicview.qml Example File
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# dynamicview.qml Example File

tutorials/dynamicview/dynamicview4/dynamicview.qml

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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: DelegateModelGroup {
                 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" ]
         }
     }