title: Include XAML Trigger To ControlTemplate
body: <p>I am pretty new with WPF and am doing some custom control stuff...
  My problem is that the code in one file is going to be way to much, so i want
  to split the code in seperate files, so other people looking in that code aren´t going to be overwhelmed.</p>
  
  <p>Okay to my question...
  I got a ResourceDictionary... the "Generic.xaml"
  In this file a got the template of an DataGrid:</p>
  
  <pre><code>    &lt;Style TargetType="{x:Type local:BADataGrid}"&gt;
      &lt;Style.Setters&gt;
          &lt;Setter Property="Control.Template"&gt;
              &lt;Setter.Value&gt;
                  &lt;ControlTemplate TargetType="local:BADataGrid"&gt;
                      &lt;Border BorderBrush="{TemplateBinding BorderBrush}" 
                          BorderThickness="{TemplateBinding BorderThickness}"
                          Background="{TemplateBinding Background}" 
                          Padding="{TemplateBinding Padding}" 
                          SnapsToDevicePixels="True"&gt;
  
             &lt;!-- *SOME TEMPLATE CODE* --&gt;
  
                      &lt;/Border&gt;
                      &lt;ControlTemplate.Triggers&gt;
                          &lt;Trigger Property="GridStyle" Value="CUSTOMER"&gt;
                              &lt;Trigger.Setters&gt;
                                  &lt;Setter Property="ColumnHeaderStyle"&gt;
                                      &lt;Setter.Value&gt;
                                          &lt;Style TargetType="{x:Type DataGridColumnHeader}"&gt;
                                              &lt;Setter Property="Background"&gt;
                                                  &lt;Setter.Value&gt;
                                                      &lt;ImageBrush&gt;
                                                          &lt;ImageBrush.ImageSource&gt;
                                                              &lt;Binding  Path="HeaderBackground" RelativeSource="{RelativeSource AncestorType=local:BADataGrid}"&gt;
                                                                  &lt;Binding.TargetNullValue&gt;
                                                                      &lt;ImageSource&gt;
                                                                          headerBack.png
                                                                      &lt;/ImageSource&gt;
                                                                  &lt;/Binding.TargetNullValue&gt;
                                                              &lt;/Binding&gt;
                                                          &lt;/ImageBrush.ImageSource&gt;
                                                      &lt;/ImageBrush&gt;
                                                  &lt;/Setter.Value&gt;
                                              &lt;/Setter&gt;
                                          &lt;/Style&gt;
                                      &lt;/Setter.Value&gt;
                                  &lt;/Setter&gt;
                              &lt;/Trigger.Setters&gt;
                          &lt;/Trigger&gt;
                      &lt;/ControlTemplate.Triggers&gt;
  
                  &lt;/ControlTemplate&gt;
              &lt;/Setter.Value&gt;
          &lt;/Setter&gt;
      &lt;/Style.Setters&gt;
  &lt;/Style&gt;
  </code></pre>
  
  <p>Now I want the "ControlTemplate.Triggers" part of the code above in another .XAML File.</p>
  
  <p>Is this even possible?</p>