activity-lifecycle

According to the android Activity Lifecycle, the only callback guaranteed to be called (if an activity ever leaves the Running state, which is typically expected) is onPause() . So, I must assume that there are scenarios in which it makes sense to implement onStop() and onDestroy() although they are not really guaranteed to be called. I understand that onStop() should be implemented when it's possible for an activity to return to the Running state via the Stopped state (why would it do that instead of returning directly is a different question). But the need for onDestroy() , when I can place

I would like to test out onSaveInstanceState and onRestoreInstanceState for my app on the emulator. I have found this , which says that we could simulate this during orientation change, but I'm storing some of my variables on the application level (subclass android.app.Application ), so the orientation change does not wipe out the variables. So my question is, how can I simulate the low memory situation thus killing of my activities? Hope I've made myself clear. Thanks You can pause your application (by pushing the Home button, simulating a call, whatever). Then kill the app's process through

Everything I've read says you can't call getWidth() or getHeight() on a View in a constructor, but I'm calling them in onResume() . Shouldn't the screen's layout have been drawn by then? @Override protected void onResume() { super.onResume(); populateData(); } private void populateData() { LinearLayout test = (LinearLayout) findViewById(R.id.myview); double widthpx = test.getWidth(); } Onik A view still hasn't been drawn when onResume() is called, so its width and height are 0. You can "catch" when its size changes using OnGlobalLayoutListener() : yourView.getViewTreeObserver()