How to access the current ListView item from qml

Question

I have an application that stores and edits notes. The list of notes is displayed as a list as follows:

Page { id: noteList title: i18n.tr("QNote") visible: false Column { anchors.fill: parent ListView { anchors.fill: parent model: notes delegate: ListItem.Standard { text: Title onClicked: editNote(NoteText, Title, modelData); progression: true } } } } function editNote(text, title, item) { pageStack.push(noteEdit, {title: title, text: text}); handler.setActiveItem(item); } 

The notes element is a NoteListModel that subclasses QAbstractListModel and contains NotesListItems. I would like to do this in order to save the currently selected NoteListItem so that I can easily access the Note object inside when the user wants to save the changed note. However, I do not know how to access backing NoteListItem from a qml delegate. modelData seems like something else. Is there any way to do this? If I could wrap the Note object in QVariant, I could easily access it through roles, but when I tried it like this,

 QVariant NoteListItem::data(int role) { switch (role) { case Title: return note.getTitle(); case NoteText: return note.getText(); case NoteObject: return QVariant::fromValue(note); default: return QVariant(); } } 

this led to a compiler error saying

qmetatype.h: 642: error: invalid application "sizeof" for the incomplete type "QStaticAssertFailure"

Or should I try to access the selected list item from the support code? Is there any way to do this? Do you have any ideas?

Thank you for your time. Regards, Peter

Answer 1

It took me a lot of time since there are many wrong solutions in Stackoverflow.

A clean way of QML is to use the DelegateModel and access it from QML as follows:

 import QtQuick 2.4 import QtQml.Models 2.1 ListView { property var currentSelectedItem onCurrentItemChanged{ // Update the currently-selected item currentSelectedItem = myDelegateModel.items.get(currentIndex).model; // Log the Display Role console.log(currentSelectedItem.display); } model: DelegateModel { id: myDelegateModel model: myAbstractItemModel delegate: { // Define delegates here } } } 

This line returns an object ( var ) that you can access in the same way as within the delegate: myDelegateModel.items.get(currentIndex).model

This example assumes that you are using only the delegate group DelegateModelGroup.

See http://doc.qt.io/qt-5/qml-qtqml-models-delegatemodel.html and http://doc.qt.io/qt-5/qml-qtqml-models-delegatemodelgroup.html# get-method method