android settings interface back navigation buttons how to achieve

set the application Settings android ActionBar

We know:
getActionBar (). setDisplayOptions (ActionBar.DISPLAY_HOME_AS_UP,
ActionBar.DISPLAY_HOME_AS_UP);
Or
getActionBar (). setDisplayShowHomeEnabled ()
You can see the back navigation buttons in back navigation page.

Set in android application code, the interface is PreferenceActivity, click on one of them, such as wifi, enter the page containing the navigation buttons back, but the code does not see a similar setup code ah?<-! Main posts under Banner (D4) -><-! Posts under the main text (D5) ->
Reply:
In the framework of the standard Actionbar controls implemented. Call to
Reply:

cited a floor ncepu307 reply:

standard Actionbar control framework is implemented. Call to

Thank you upstairs to answer, I would like to know the settings click on the entry "fallback navigation" obviously exists, but do not know where to write specific code?