TabItem in a separate XAML

Question

Is it possible to put a TabItem into a separate XAML and reference something like this:

Answer 1

The previous answer from Tony Borres already covers the most important aspects. But the further comment asks for access from code behind. So I will extend the example from Tony to show this aspect, too. This answer shows the required namespaces. I have added them to the answer from Tony, too.

To simply make the code more manageable it is recommended to define each tab's data in a user control, but still have the TabItem in the main tab control. This strategy is useful for example to work around FxCop CA1505: "Avoid unmaintainable code" when using a tab control with several tab items.

Let's assume that this is the original code:

To make the code more manageable the tab contents can be moved into a UserControl such as:

And then is possible to use the new user control in the TabControl like this:

Now it possible to access the inner wigdets of the user control from main window and vice versa. Please note the "x:" in front of the user control's name.

public partial class MainWindow : Window
{
    private void AccessWidgetWithinUserControl()
    {
        ucTab1Data.txtData1.Text = "New text on Tab 1";
    }
}

public partial class Tab1Data : UserControl
{
    private MainWindow mainWindow = null; // Reference to the MainWindow

    public Tab1Data()
    {
        InitializeComponent();
    }

    // get a reference to main windows when it is available.
    // The Loaded Event is set in the XAML code above.
    private void OnControlLoaded(object sender, RoutedEventArgs e)
    {
        mainWindow = Window.GetWindow(this) as MainWindow;
    }

    private void AccessMainWindowsWidget()
    {
        mainWindow.txtData2.Text = "New text on Tab 2 in the main window";
    }
}

The shown code to access txtData2 would be the same even if is embedded in its own user control.