title: Binding one dependency property to another
body: <p>I have a custom Tab Control that I have created, but I am having an issue. I have an Editable TextBox as part of the custom TabControl View.</p>
  
  <pre><code>&lt;Controls:EditableTextControl x:Name="PageTypeName" 
                                    Style="{StaticResource ResourceKey={x:Type Controls:EditableTextControl}}" Grid.Row="0" TabIndex="0" 
                                    Uid="0"
                                    AutomationProperties.AutomationId="PageTypeNameTextBox"
                                    AutomationProperties.Name="PageTypeName"
                                    Visibility="{Binding ElementName=PageTabControl,Path=ShowPageType}"&gt;
          &lt;Controls:EditableTextControl.ContextMenu&gt;
              &lt;ContextMenu x:Name="TabContextMenu"&gt;
                  &lt;MenuItem Header="Rename Page Type" Command="{Binding Path=PlacementTarget.EnterEditMode, RelativeSource={RelativeSource AncestorType=ContextMenu}}" 
                            AutomationProperties.AutomationId="RenamePageTypeMenuItem"
                            AutomationProperties.Name="RenamePageType"/&gt;
                  &lt;MenuItem Header="Delete Page Type" Command="{Binding Path=PageTypeDeletedCommand}" 
                            AutomationProperties.AutomationId="DeletePageTypeMenuItem"
                            AutomationProperties.Name="DeletePageType"/&gt;
              &lt;/ContextMenu&gt;
          &lt;/Controls:EditableTextControl.ContextMenu&gt;
          &lt;Controls:EditableTextControl.Content&gt;
              &lt;!--&lt;Binding Path="CurrentPageTypeViewModel.Name" Mode="TwoWay"/&gt;--&gt;
              &lt;Binding ElementName="PageTabControl" Path="CurrentPageTypeName" Mode ="TwoWay"/&gt;
          &lt;/Controls:EditableTextControl.Content&gt;
      &lt;/Controls:EditableTextControl&gt;
  </code></pre>
  
  <p>In the Content section I am binding to a Dependency Prop called CurrentPageTypeName. This Depedency prop is part of this custom Tab Control.</p>
  
  <pre><code>public static DependencyProperty CurrentPageTypeNameProperty = DependencyProperty.Register("CurrentPageTypeName", typeof(object), typeof(TabControlView));
      public object CurrentPageTypeName
      {
          get { return GetValue(CurrentPageTypeNameProperty) as object; }
          set { SetValue(CurrentPageTypeNameProperty, value); }
      }
  </code></pre>
  
  <p>In another view, where I am using the custom TabControl I then bind my property, with the actual name value, to CurrentPageTypeName property as seen below:</p>
  
  <pre><code> &lt;Views:TabControlView Grid.Row="0" Name="RunPageTabControl" 
                            TabItemsSource="{Binding RunPageTypeViewModels}"                              
                            SelectedTab="{Binding Converter={StaticResource debugConverter}}" 
                            CurrentPageTypeName="{Binding Path=RunPageName, Mode=TwoWay}" 
                            TabContentTemplateSelector="{StaticResource tabItemTemplateSelector}"  
                            SelectedIndex="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}, Path=DataContext.SelectedTabIndex}"
                            ShowPageType="Hidden" &gt;           
          &lt;!--&lt;Views:TabControlView.TabContentTemplate&gt;
              &lt;DataTemplate DataType="{x:Type ViewModels:RunPageTypeViewModel}"&gt;
                  &lt;RunViews:RunPageTypeView/&gt;
              &lt;/DataTemplate&gt;
          &lt;/Views:TabControlView.TabContentTemplate&gt;--&gt;
  
      &lt;/Views:TabControlView&gt;
  </code></pre>
  
  <p>My problem is that nothing seems to be happening. It is grabbing its Content from the Itemsource, and not from my chained Dependency props. Is what I am trying even possible? If so, what have I done wrong.</p>
  
  <p>Thanks for looking. </p>