DISPLAY_HOME_AS_UP
Display the 'home' element such that it appears as an 'up' affordance. e.g. show an arrow to the left indicating the action that will be taken. Set this flag if selecting the 'home' button in the action bar to return up by a single level in your UI rather than back to the top level or front page.
Setting this option will implicitly enable interaction with the home/up button. See setHomeButtonEnabled.