Question

I am building a small Windows Phone application which has a databound ListBox as a main control. DataTemplate of that ListBox is a databound ItemsControl element, which shows when a person taps on a ListBox element.

Currently, I am accessing it by traversing the visual tree of the application and referencing it in a list, and than getting the selected item through SelectedIndex property.

Is there a better or more effective way?

This one works currently, but I am afraid if it would stay effective in case of larger lists.

Thanks

Answer 1

Have you tried wiring the SelectionChanged event of the ListBox?

<ListBox ItemsSource="{Binding}" SelectionChanged="ListBox_SelectionChanged">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <!-- ... -->
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

With this in the code behind:

private void ListBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    ListBox listBox = sender as ListBox;

    // nothing selected? ignore
    if (listBox.SelectedIndex != -1)
    {
         // something is selected
    }

    // unselect the item so if they press it again, it takes the selection
    listBox.SelectedIndex = -1;
}