This is an Android Beginner Video Tutorial which is giving you a visual presentation of Android activity life cycle. Activity is the basic building block for the android application and it goes through a life cycle, so in this Android Video Tutorial, you will find all the details regarding activity life cycle and "Saving data Across Rotation". 

Activity has four states:-
1) When activity is in the foreground.
2) In pause states, Activity loses focus but remain visible.
3) If an activity is no longer visible to the user than it in the stop state.
4) when an activity is killed by the system.
 

And the next topic covered "Saving data Across rotation":
Whenever we change the orientation of the screen, activity is destroyed by the system and again it calls the onCreate() method, so it can lose some data. So to make sure that no data is lost, we need to properly save and restore data by overriding the onSaveInstanceState(Bundle outState) method.

This Vlog clearly represents how and when different methods are called in an android life cycle. Here this android video tutorial, activity life cycle follow methods are called at different places. The methods involved in this life cycle are onCreate( ), onStart( ), onResume( ), onPause( ), onStop( ), OnRestart( ) and finally onDestroy method will be called. Watch the video for more understanding.

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