Use Navigation History in Eclipse RCP

Question

I like to use the navigation history provided by Eclipse in my RCP Application. Unfortunately this feature isn't well documented. In fact I only found this Wiki entry: http://wiki.eclipse.org/FAQ_How_do_I_hook_my_editor_to_the_Back_and_Forward_buttons%3F

It mentions that every editor can be marked in the navigation history, without having to specify a location. This is exactly what I want.

Regardless of whether the specific editor has any support for navigation history, markLocation will work. If the editor doesn’t implement INavigationLocationProvider, a history entry will be added, allowing the user to jump back to that editor but without returning to any particular location.

I added the following lines of code to my application in order to add a navigation entry each time a new Editor is opened.

IWorkbenchPage page = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage();
IEditorPart editor = page.openEditor( input, MyEditor.ID );
page.getNavigationHistory().markLocation( editor );

My problem is that the code doesn't work. The toolbar icons for the commands org.eclipse.ui.navigate.backwardHistory and org.eclipse.ui.navigate.forwardHistory stay grayed out.

Answer 1

I have found the solution. In order to use the Navigation History in your Eclipse RCP application you have to add the following lines of code to your ApplicationActionBarAdvisor.

/**
 * Fills the cool bar with the main toolbars for the window.
 * <p>
 * The default implementation does nothing. Subclasses may override.
 * </p>
 * 
 * @param coolBar
 *            the cool bar manager
 */
protected void fillCoolBar( ICoolBarManager coolBar ) {
    IToolBarManager navigation = new ToolBarManager( SWT.FLAT );

    IAction backward = getAction( IWorkbenchCommandConstants.NAVIGATE_BACKWARD_HISTORY );
    IAction forward = getAction( IWorkbenchCommandConstants.NAVIGATE_FORWARD_HISTORY );

    navigation.add( backward );
    navigation.add( forward );

    coolBar.add( navigation );
}

/**
 * Instantiates the actions used in the fill methods. Use
 * {@link #register(IAction)} to register the action with the key binding
 * service and add it to the list of actions to be disposed when the window
 * is closed.
 * 
 * @param window
 *            the window containing the action bars
 */
protected void makeActions( IWorkbenchWindow window ) {
    IAction backward = ActionFactory.BACKWARD_HISTORY.create( window );
    backward.setId( IWorkbenchCommandConstants.NAVIGATE_BACKWARD_HISTORY );
    IAction forward = ActionFactory.FORWARD_HISTORY.create( window );
    forward.setId( IWorkbenchCommandConstants.NAVIGATE_FORWARD_HISTORY );

    register( backward );
    register( forward );
}

Answer 2

You have to implement the INavigationLocationProvider interface in your editor.

You can see how the Eclipse group implemented the interface in their AbstractTextEditor.