Example that shows how to determine if the ActionBar is currently in overlay mode.

IsMyActionBarInOverlay.java

public class MyActivity extends Activity {
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if(windowActionBarOverlay()) {
      // Do something
    }
  } 
  
  private boolean windowActionBarOverlay() {
    TypedValue attributeValue = new TypedValue();
    getTheme().resolveAttribute(android.R.attr.actionBarStyle, attributeValue, true);
    
    TypedArray a = getTheme().obtainStyledAttributes(attributeValue.data, new int[] {android.R.attr.windowActionBarOverlay});
    boolean isOverlaid = a.getBoolean(0, false);
    a.recycle();
    
    return isOverlaid;
  }

}