mainOwnDelegate.qml

import QtQuick

Window {
    width: 600
    height: 400
    visible: true

    TreeView {
        anchors.fill: parent
        id: _view

        // The model needs to be a QAbstractItemModel
        model: _model
        delegate: Item {
            id: treeDelegate

            implicitWidth: padding + label.x + label.implicitWidth + padding
            implicitHeight: label.implicitHeight * 1.5

            readonly property real indent: 20
            readonly property real padding: 5

            // Assigned to by TreeView:
            required property TreeView treeView
            required property bool isTreeNode
            required property bool expanded
            required property int hasChildren
            required property int depth

            TapHandler {
                onTapped: {
                    treeView.toggleExpanded(row)
                    var qi = _view.index(row, 0)
                    console.log(qi)
                    _view.model.showQModelIndex(qi)
                }
            }

            Text {
                id: indicator
                visible: treeDelegate.isTreeNode && treeDelegate.hasChildren
                x: padding + (treeDelegate.depth * treeDelegate.indent)
                anchors.verticalCenter: label.verticalCenter
                text: "▸"
                rotation: treeDelegate.expanded ? 90 : 0
            }

            Text {
                id: label
                x: padding + (treeDelegate.isTreeNode ? (treeDelegate.depth + 1)
                                                        * treeDelegate.indent : 0)
                width: treeDelegate.width - treeDelegate.padding - x
                clip: true
                text: model.display
            }
        }
    }
}