Reading-notes

Understand Tasks and Back Stack

• What is a Stack? => stack is a collection of activities , so each task is a collection of activities, however these will be arranged in the back stack, after finishing the task it will be popped from the stack.

Managing Tasks

• This is done by doing all activites started in succession in the same task , following the STACK concept FILO. first things first we should call setContentView() to define the layout for the activity’s user interface.

• When onCreate() finishes, the next callback is always onStart().
• onStart() its the same of onCreate() the activity becomes visible to the user.
• onResume() this would be invoked by the system before the activity starts interacting with the user.
• The onPause() callback always follows onResume()
• onPuase() this may be called if the user pressed back button. so we can say when the activity loses focus.
• onStop() when the activity is no longer visible to the user.
• onRestart() it be invoked when the activity is stipped and state is about to restart.
• onDestroy() it’s implemented to ensure that all of an activity’s resources are released when the activity, or the process containing it, is destroyed.