How to remove a Category from Import wizard in Eclipse-RCP?

Question

I need to add an import wizard into my eclipse-rcp app. For that I would like to use existing wizard with only my categories. I found couple of examples in the Internet, but

Answer 1

You can choose which contributions are visible in your RCP application by using org.eclipse.ui.activities extension point with appropriate activityPatternBinding (despite of what they say at the page that you linked).

Using this extension point you can define one activity with a pattern that matches anything but your own contributions (e.g. pattern="[^\.]++\.(?!myplugin).*" matches contributions wiht ID-s not starting with com.myplugin). This activity, when not being enabled, will exclude all the contributions from UI except your own.

With another acitvity you will define a pattern that includes the contributions that you'd like to include from other plugins (e.g. pattern=".*file\.import" matches the Import... menu item in File menu). This is the activity that you will enable in your WorkbenchAdvisor using

PlatformUI.getWorkbench().getActivitySupport().setEnabledActivityIds(...);

Please note that this particular solution will disable (almost) all of the Eclipse contributions except File > Import... It will take quite a bit of digging if you want to have a lot of functionality enabled and only small parts disabled. But it's mostly possible to figure out correct patterns to achieve this.