How to listen Android ActivityTestRule's beforeActivityLaunched method in an android test

Question

How do I listen ActivityTestRule's beforeActivityLaunched() method in an android test.

My workaround is creating a custom ActivityTestRule and providing a callback on constructor. Is it a bad practice? Same way is it OK to listen for ActivityTestRule constructor method.

Here is my code:

public class CustomActivityTestRule<A extends Activity> extends ActivityTestRule<A> {

    public interface onBeforeListener{
        void onBefore(String message);
    }

    private onBeforeListener listener;

    public CustomActivityTestRule(Class<A> activityClass, onBeforeListener listener) {
        super(activityClass);
    }

    @Override
    protected void beforeActivityLaunched() {
        super.beforeActivityLaunched();
        listener.onBefore("before activity launch");
    }
}

In android test class, I can do something like:

@Rule public CustomActivityTestRule<MainActivity> mainActivityActivityTestRule = new
            CustomActivityTestRule<MainActivity>(MainActivity.class, new CustomActivityTestRule.onBeforeListener() {
        @Override
        public void onBefore(String message) {
            //do something before activity starts
        }
    });

Same way it is able to do something on junit rule instantiating. Is there any other way to listen for junit test rule instantiating?

Answer 1

You can override beforeActivityLaunched without creation of a new class.

I'm using the following in my tests:

@Rule
public ActivityTestRule<MainActivity> mainActivityActivityTestRule = new ActivityTestRule<MainActivity>(MainActivity.class) {

    @Override
    protected void beforeActivityLaunched() {
        super.beforeActivityLaunched();
    }

};