Hide Status Bar In Non Rooted Device

Hide Status Bar In Non Rooted Device

How to hide status bar of tab in non rooted device? I am Using Android
4.0.4 I used like this but it is not working for me...please suggest any
solution
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// hide titlebar of application
// must be before setting the layout
requestWindowFeature(Window.FEATURE_NO_TITLE);
// hide statusbar of Android
// could also be done later
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.main);