How to save an Android Activity state using save instance state?

manpreet Best Answer 2 years ago

_x000D_ You need to override onSaveInstanceState(Bundle savedInstanceState) and write the application state values you want to change to the Bundle parameter like this: @Override public 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 would then extract the values like this: @Override public 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 would usually use this technique to store instance values for your application (selections, unsaved text, etc.).