WP7 listbox selection changed event does not fire in a content control style

Question

I have been scratching my head on why the selection changed event for a listbox does not fire. I have a panaroma items being created dynamically in the code behind... Kind of new to wpf/xaml

<Style x:Key="PanoramaItemStyle" TargetType="ContentControl">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ContentControl">
                <Grid>
                    <controls:PanoramaItem x:Name="ItemLocationPanoramaItem" Header="{Binding TagName}">
                        <ListBox  ItemsSource="{Binding ItemLocators}" Height="496" SelectedItem="{Binding SelectedItemLocation, Mode=TwoWay}" SelectionChanged="ItemLocatorsList_SelectionChanged" >
                            <ListBox.ItemsPanel>
                                <ItemsPanelTemplate >
                                    <StackPanel Orientation="Vertical"  ScrollViewer.VerticalScrollBarVisibility="Auto" />
                                </ItemsPanelTemplate>
                            </ListBox.ItemsPanel>
                            <ListBox.ItemTemplate>
                                <DataTemplate>
                                    <StackPanel>
                                        <StackPanel Orientation="Horizontal" Margin="0,0,0,17">
                                            <StackPanel Width="311">
                                                <TextBlock Text="{Binding Item.Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextLargeStyle}"/>
                                                <TextBlock Text="{Binding Location.Description}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}"/>
                                            </StackPanel>
                                        </StackPanel>
                                    </StackPanel>
                                </DataTemplate>
                            </ListBox.ItemTemplate>
                        </ListBox>
                    </controls:PanoramaItem>
                    <ContentPresenter/>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
    <Setter Property="Foreground" Value="White"/>
</Style>

This is in the codebehind for the view.

 public LocationGroups()
    {
        InitializeComponent(); 
        LocationGroupsPanaroma.DefaultItem = LocationGroupsPanaroma.Items[0];
        viewModel = this.DataContext as LocationGroupsViewModel;
        CreateDynamicPanaromaItems();
    }


    private void CreateDynamicPanaromaItems()
    {
        foreach (Model.LocationGroup group in viewModel.LocationGroups)
        {
            if (group.TotalItems > 0)
            {
                PanoramaItem pi = new PanoramaItem();
                pi.Header = group.Name;
                pi.Orientation = System.Windows.Controls.Orientation.Horizontal;
                ItemLocationListViewModel itemLocationViewModel = viewModel[group.LocationGroupId];
                pi.DataContext = itemLocationViewModel;
                pi.Style = Resources["PanoramaItemStyle"] as Style; 
                LocationGroupsPanaroma.Items.Add(pi);
            }
        }

    }

You are going to have to provide a bit more information about what your problem actually is! You mention a ListBox SelectionChanged event is not firing, but your code snippets are all about populating a Panorama control. I would firstly, simplify your code until it is the simplest example that illustrates your problem, then update your question. — ColinE, Jul 11 '11 at 07:19
What is your question? Your included code doesn't include anything that can be identified as definitely being a Listbox. There is also no reference to teh SelectionChanegd event. Ad why the `mvvm-light` tag? Again, there's nothing in the code which refers to it? — Matt Lacey, Jul 11 '11 at 07:21
Can someone edit my original post.. wonder why the xaml is not showing up. I checked the other posts..and that doesn't address this specific problem — pal Khoa, Jul 12 '11 at 02:07
Code and Xml need to be prefixed with at last 4 spaces or 1 tab to be formatted as code. Your first line of your Xaml did not have any indentation, and therefore the following block was not trated as code and hidden. — AxelEckenberger, Jul 14 '11 at 08:04
The code and the XAML do not match (different variable names etc.), also **what** are you trying to do? Furthermore, consider whether you **need** the code behind (see the answers in my post). — AxelEckenberger, Jul 15 '11 at 05:13

score 1 · Answer 1 · answered Aug 11 '11 at 15:11

if you were using mvvm light you could do the following (fill your code in for the <> remarks:

<i:Interaction.Triggers>
  <i:EventTrigger EventName="SelectionChanged">
    <mvvm:EventToCommand 
    Command="{Binding <yourviewmodel>.<yourrelaycommand>, Mode=OneWay, Source={StaticResource Locator}}" CommandParameter="{Binding SelectedValue, ElementName=<nameofyourlistbox>}"/>
  </i:EventTrigger>

score 0 · Answer 2 · edited May 23 '17 at 11:55

0

See my answers to this post and this post on how to dynamically generate panorama items and list boxes using mvvm, i.e. with no code behind.

edited May 23 '17 at 11:55

Community

1
1

answered Jul 11 '11 at 11:52

AxelEckenberger

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WP7 listbox selection changed event does not fire in a content control style

2 Answers2