Code-behind for DataTemplate in a ResourceDictionary

I am attempting to use code-behind to support an event handler in a DataTemplate. The below code works fine when it is the code-behind for a Window, but not for a ResourceDictionary. The code will not even compile when put in the code-behind for the ResourceDictionary.

I know that Commands is the better option here, but this is largely a test to make sure I can handle events on resources in a ResourceDictionary, if needed. My goal is to better organize my code, but this is not the straightforward "include" behavior that I thought a separate ResourceDictionary file would provide.

In MainWindow.xaml:

    <Window x:Class="Wizbang.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:my="clr-namespace:DevComponents.WpfEditors;assembly=DevComponents.WpfEditors"
        xmlns:diag="clr-namespace:System.Diagnostics;assembly=WindowsBase"
        xmlns:local ="clr-namespace:Wizbang"
        xmlns:m ="clr-namespace:Wizbang.Model"
        xmlns:vm="clr-namespace:Wizbang.ViewModel"
        xmlns:vw="clr-namespace:Wizbang.View"
        DataContext="{Binding Path=Main, Source={StaticResource Locator}}"
        Title="Wizbang" Height="760" Width="1335" WindowStartupLocation="CenterScreen">

        <Window.Resources>
            <ResourceDictionary>
                 <ResourceDictionary Source="Resources/MainWindowResources.xaml" />
            </ResourceDictionary>
        </Window.Resources>

In code-behind MainWindow.xaml.cs and MainWindowResources.xaml.cs, the same code:

private void btnSave_Click(object sender, RoutedEventArgs e)
        {
            //switch item template
            Button btn = (Button)sender;
            //command contains the list item
            ContentControl itm = (ContentControl)btn.CommandParameter;

            itm.SetValue(ContentTemplateProperty, this.FindResource("DetailedTemplate") as DataTemplate);

            //this.UpdateLayout();

        }

When I keep the ResourceDictionary inline in MainWindow.xaml, and put the code-behind in MainWindow.xaml.cs, everything works. When I attempt to use a separate file for ResourceDictionary, the code does not compile. The compiler complains about the last line:

itm.SetValue(ContentTemplateProperty, this.FindResource("DetailedTemplate") as DataTemplate);

The this.FindResource() is not a valid method, and "ContentTemplateProperty" is not found:

Error 4 The name 'ContentTemplateProperty' does not exist in the current context C:...\Visual Studio 2010\Projects\Wizbang\Wizbang\Resources\MainWindowResources.xaml.cs 36 26 Wizbang

Error 5 'Wizbang.Resources.MainWindowResources' does not contain a definition for 'FindResource' and no extension method 'FindResource' accepting a firs开发者_开发百科t argument of type 'Wizbang.Resources.MainWindowResources' could be found (are you missing a using directive or an assembly reference?) C:...\Visual Studio 2010\Projects\Wizbang\Wizbang\Resources\MainWindowResources.xaml.cs 36 56 Wizbang

If I remove that last line, the code compiles and runs, but the button has no functionality. I think my issue is mapping that last line's references from the perspective of a ResourceDictionary, but I am not sure why it should be different.

Thanks for any thoughts.

Bill

This is because the code no longer is in the window class. You have to find it again (or whatever control you want to place the template on).

Window parentWindow = Window.GetWindow(btn);
itm.SetValue(Window.ContentTemplateProperty, parentWindow.FindResource("DetailedTemplate") as DataTemplate);

I think that using Commands would be a much cleaner approach.