To use Theme.Holo (or its descendants) for Android 3.0 or higher to show ActionBar.
android:theme="@android:style/Theme.Holo"
To hide Action Bar use Theme.Holo.NoActionBar or Theme.Holo.NoActionBar.Fullscreen.
android:theme="@android:style/Theme.Holo.NoActionBar"
android:theme="@android:style/Theme.Holo.NoActionBar.Fullscreen"
Related:
- Show and hide ActionBar using Java code