How to execute the same function in the onCreate method of all activities?

Issue

What is the problem?

I want to add this custom window callback in each activity already implemented in the app, currently I need to manually modify the code of the onCreate method of each activity or make it inherit a class that already has onCreate in the desired way, but I need that this process could be performed without modifying the app's existing code, just adding some initialization.

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    window.callback = CustomCallback(window.callback, this)
}

Solution

Inside you app Application Class (you'll need to create one, if not done yet), on "onCreate" method, call

 registerActivityLifecycleCallbacks(new ActivityLifecycleCallbacks() {

        @Override
        public void onActivityCreated(Activity activity, Bundle savedInstanceState) {

           //Code here will run for every activity

        }
 }

Answered By - Filipe Oliveira