Qt6 QML Treeview get the modelIndex of selected item

I have a working treemodel, called myModel (derived from QAbstractItemModel) in C++ and I can show it in QML using the QML Treeview control and the TreeViewDelegate

When the mouse is pressed on one treeview item, I want to pass a QModelIndex (or parameters which I can use in C++ for constructing a QModelIndex) back to C++ for further processing.

I can use the model.index but this gives me the index in the view (which corresponds to the selected row), but not a useable QModelIndex. Also I experiemented with the depth of the treeview. But I am stuck.

Has anyone a solution?

BTW: I am using Qt6.4. I found something for Qt5, which is now archived (QML: How to get the QModelIndex in a delegate inside a TreeView).

This is the code where I try to investigate the behaviour of the treeview (the call to _controller(...) is the entry point back to C++:

TreeView {
            id: garminDrives
            Layout.fillHeight: true
            Layout.fillWidth: true
            Layout.preferredHeight: root.height
            Layout.preferredWidth: root.width

            delegate: TreeViewDelegate {

                MouseArea {
                    anchors.fill: parent
                    onClicked: {
                        console.log("Tree item tapped. Model name = " + model.name
                                    + " Index to be passed back to C++ = " + model.index,
                                    " Depth = " + garminDrives.depth(model.index) + " row =  "
                                    + model.row + " col = " + model.column
                                    + " currentRow = " + garminDrives.currentRow
                                    + " currentCol = " + garminDrives.currentCol
                                    )

                        _controller.getSelectedRow(model.index)
                    }
                }

                contentItem: Label {
                    id: delegatetext
                    text: model.name
                }
            }
            model: myModel
        }

Just simplified the QML

TreeView {
    id: treeView

    anchors.fill: parent

    delegate: TreeViewDelegate {
        id: treeDelegate
        text: model.display
        onClicked: {

            var mi = treeDelegate.treeView.index(row, column)
            console.log("model.index =", mi)
            treeView.model.showQModelIndex(mi)
        }
    }
    model: _model
}

}

The QModelIndex is simply treeDelegate.treeView.index(row, column).

You can find the complete example on Github: https://github.com/d029940/QmlTreeview