You need to override onSaveInstanceState(Bundle savedInstanceState) and write the application state values you want to change to the Bundle parameter like this:

@Overridepublic void onSaveInstanceState(Bundle savedInstanceState) {  super.onSaveInstanceState(savedInstanceState);  // Save UI state changes to the savedInstanceState.  // This bundle will be passed to onCreate if the process is  // killed and restarted.  savedInstanceState.putBoolean("MyBoolean", true);  savedInstanceState.putDouble("myDouble", 1.9);  savedInstanceState.putInt("MyInt", 1);  savedInstanceState.putString("MyString", "Welcome back to Android");  // etc.} The Bundle is essentially a way of storing a NVP ("Name-Value Pair") map, and it will get passed in to onCreate and also onRestoreInstanceState where you'd extract the values like this:@Overridepublic void onRestoreInstanceState(Bundle savedInstanceState) {  super.onRestoreInstanceState(savedInstanceState);  // Restore UI state from the savedInstanceState.  // This bundle has also been passed to onCreate.  boolean myBoolean = savedInstanceState.getBoolean("MyBoolean");  double myDouble = savedInstanceState.getDouble("myDouble");  int myInt = savedInstanceState.getInt("MyInt");  String myString = savedInstanceState.getString("MyString");}You did usually use this technique to store instance values for your application (selections, unsaved text, etc.).

 

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