Question

I have a ListBox with a DataTemplate. The template has a Button on it. When the Button is clicked I want to do some logic with the object that is each row (in this case an object called WorkItemTypeMappings).

In theOnClick how can I go from the Button (object sender) to the object that is row that the button is on?

Here is the XAML of my ListBox:

<ListBox ItemsSource="{Binding Source={StaticResource WorkItemTypeMappingsCollectionView}}" HorizontalContentAlignment="Stretch" ScrollViewer.HorizontalScrollBarVisibility="Disabled" Name="lstWITypes">
    <ListBox.GroupStyle>
        <x:Static Member="GroupStyle.Default"/>
    </ListBox.GroupStyle>
    <ListBox.ItemTemplate>
        <DataTemplate>
            <Grid HorizontalAlignment="Stretch">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="2*"/>
                    <ColumnDefinition Width="2*"/>
                    <ColumnDefinition Width="50"/>
                </Grid.ColumnDefinitions>
                <TextBlock Grid.Column="0" Text="{Binding SourceType, Converter={StaticResource WorkItemTypeToStringConverter}}"/>
                <ComboBox Grid.Column="1" SelectedItem="{Binding DestType}" ItemsSource="{Binding WorkItemTypesForCurrentDestProject, Source={x:Static loc:MainMediator.Instance}, diagnostics:PresentationTraceSources.TraceLevel=High}" DisplayMemberPath="Name" />

                <!-- This is the button-->
                <Button Grid.Column="2" Content="{Binding PercentMapped}" 
                        Click="ManualMappingClick"/>
            </Grid>
        </DataTemplate>                                        
    </ListBox.ItemTemplate>
</ListBox>

Answer 1

What you can do as an alternative is to use Command instead of Event. If you bind your button to a command and pass along with it a command parameter, you should be able to get the item that is related to that button. Example code:

<!-- This is the button-->
 <Button
     Grid.Column="2"
     Content="{Binding PercentMapped}" 
     Command="SolutionNamespace:CommandClass.ButtonClickedCommand"
     CommandParameter="{Binding}" />

I am not sure how familiar you are with WPF commanding but you will notice that the CommandParameter binds to the context without a path name, that is to say it binds to the WorkItemTypeMappings that you need.

Command Example Code:

public static SimpleCommand ButtonClickedCommand { get; set; }

static CommandClass()
{
    ButtonClickedCommand = new SimpleCommand
                           {
                               ExecuteDelegate =
                               x=> ButtonClicked(x as WorkItemTypeMappings)
                           };
}


public static ButtonClicked(WorkItemTypeMappings mappings)
{
    if(mappings != null) MessageBox.Show(mapping.PercentMapped)
}

You will notice that the ButtonClickedCommand is static, this is required because the button cannot access the command from its current binding context.

SimpleCommand is just a simplified implementation of the ICommand, can Google this one if you’re not sure. I hope this is not an overkill to your problem, but you cannot go wrong with WPF Commands.

Good luck.