A dynamic C++ model and a QML ListView

Question

I'm using a QML list view which displays one element at a time

 ListView
 {
      model: cppobj.list
      ...
 }

cppobj is a C++ object which can be modified, i.e. items can be removed, appended, etc. If an element is appended, the ListView goes back to the first element. What's more ListView.onRemove is not called. Any ideas how to cope with it?

Thanks

/edit: the append function of the C++ object looks like that:

void append (QString str) { m_list.append(str); emit listChanged(m_list); }

[check this](http://stackoverflow.com/questions/22249521/is-it-possible-to-use-qabstracttablemodel-with-tableview-from-qtquick-controls/22265242#22265242) — Redanium, Oct 07 '14 at 22:36

score 3 · Accepted Answer · answered Oct 04 '14 at 18:28

3

You need to use QAbstractListModel. See documentation here.

answered Oct 04 '14 at 18:28

Oleg Shparber

2,732
1
18
19

And is there any Model class for QStrings (so that there's less to implement)? the `m_list` in my case was QStringList? – marmistrz Oct 04 '14 at 18:37
1

You can expose `QStringList` through a property, but `QAbstractListModel` is the only way to make the view update on per-item basis. – Oleg Shparber Oct 04 '14 at 19:43
And the `QStringListModel` class? It inherits `QAbstractListModel`. – marmistrz Oct 04 '14 at 19:59
1

Yeah, `QStringListModel` would do the job. – Oleg Shparber Oct 04 '14 at 20:07

score 0 · Answer 2 · answered Feb 04 '19 at 14:29

In case you want to have a ListModel for variant JSON data that you can use directly in QML, you can have a look at the JsonListModel. It can synchronize JSON data to a ListModel so you do not lose the current scroll position of the list. You can also apply transition animations and have the full ListView/ListModel features available.

 ListView
 {
      model: JsonListModel {
          source: myJsonData
          keyField: "id"
      }
      ...
 }

You can find a detailed guide how to use the JsonListModel here:

A dynamic C++ model and a QML ListView

2 Answers2