Actionbar navigation bar learning

actionBar Study

//public class MainActivity extends Activity {
// ActionBar actionBar;
//
// @Override
// protected void onCreate(@Nullable Bundle savedInstanceState) {
// super.onCreate(savedInstanceState);
// setContentView(R.layout.actionbar);
// // Get change activity Of actionBar
// // Only when the application theme is not closed actionbar when , This code can be returned actionbar
// actionBar=getActionBar();
// }
// // To show the actionbar Button defines the event handling method
// public void showActionBar(View source){
// // Show actionbar
// actionBar.show();
// }
// // For hiding actionbar Button defines the event handling method
// public void hideActionBar(View source){
// // hide actionbar
// actionBar.hide();
// }
//}

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