A better way of forcing data bound WPF ListBox to update?

TimothyP picture TimothyP · Oct 31, 2008 · Viewed 58.6k times · Source

I have WPF ListBox which is bound to a ObservableCollection, when the collection changes, all items update their position.

The new position is stored in the collection but the UI does not update. So I added the following:

    void scenarioItems_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
    {
        ToolboxListItem.UpdatePositions();
        lstScenario.ItemsSource = null;
        lstScenario.ItemsSource = ToolboxListItem.ScenarioItems;
        this.lstScenario.SelectedIndex = e.NewStartingIndex;
    }

By setting the ItemsSource to null and then binding it again, the UI is updated,

but this is probably very bad coding :p

Suggestions?

Answer

Gishu picture Gishu · Oct 31, 2008

I have a Listbox bound to an object property which is of type List<MyCustomType>() and I verified that the following code updates the listbox when the List is updated.

void On_MyObjProperty_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
{
   MyListBox.Items.Refresh();
}

If you're still facing issues, scan the VS IDE output window (Ctrl+W, O) and see if you can spot any binding errors reported.