Request that the visibility of the NavigationBar be changed. For Phone UI Mode of ICS

Application can request that the visibility of the NavigationBar be changed.
But, be careful of timing be released from the Frameworks.

How to Request that the visibility of the NavigationBar

To request that the visibility of the NavigationBar be changed, you can use View#setSystemUiVisibility().

Android Developer: View#setSystemUiVisibility()

1. register Listener to View - View#setOnSystemUiVisibilityChangeListener
2. set Visivility mode - View#setSystemUiVisibility

Visivility mode:

• View.SYSTEM_UI_FLAG_LOW_PROFILE  - navigation icons may dim 
• View.SYSTEM_UI_FLAG_HIDE_NAVIGATION - hide navigation icons

Example:

{
                   :
 View view;
 view = findViewById(R.id.linerLayout);
         view.setOnSystemUiVisibilityChangeListener(mOnSystemUiVisibilityChangeListener);
 view.setSystemUiVisibility(View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);
                   :
}

private OnSystemUiVisibilityChangeListener mOnSystemUiVisibilityChangeListener = new OnSystemUiVisibilityChangeListener(){

 @Override
 public void onSystemUiVisibilityChange(int visibility) {
  Log.e("","call onSystemUiVisibilityChange = " + visibility);
 }
};

View.SYSTEM_UI_FLAG_LOW_PROFILE
NavigationBar display area of ​​the intact, but appear dimmed.

View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
Hide the display area of ​​the NavigationBar becomes completely, spread the display area of ​​the application.

Timing be released from the Frameworks

NavigationBar display specifiers will be released in the following use cases.

• TouchDown on Screen
• Show PowerDown Dialog(GlobalActions)
• An application becomes active/inactive