How can I refresh the ActionBar when onPrepareOptionsMenu switched menu entries?

Question

Within my apps I often enable/disable menu entries and do make them visible from onPrepareOptionsMenu.

Today I started to add the android:showAsAction menu attribute to some of my Android 2.x apps to show menu entries used most on the ActionBar.

The ActionBar does not reflect the enable/disable and visibility immediately. I need to click on the menu dropdown on the right to see this change happen.

Ok, I do understand that the menu fires onPrepareOptionsMenu. But what do I need to do to refresh the ActionBar? I think this change needs to be applied from within onOptionsItemSelected but I don't know what I should call.

Here's the menu:

<item     android:icon="@drawable/ic_menu_mapmode"     android:id="@+id/men_mapview"     android:showAsAction="ifRoom|withText"     android:title="@string/txt_mapview" />  <item     android:icon="@drawable/ic_menu_mapmode"     android:id="@+id/men_satelliteview"     android:showAsAction="ifRoom|withText"     android:title="@string/txt_satelliteview" /> 

Here's the onPrepareOptionsMenu:

@Override public boolean onPrepareOptionsMenu(final Menu menu) {     MenuItem menuItemMapView = menu.findItem(R.id.men_mapview);     MenuItem menuItemSatelliteView = menu.findItem(R.id.men_satelliteview);      if (mapView.isSatellite()) {         menuItemMapView.setEnabled(true).setVisible(true);         menuItemmenuItemSatelliteView.setEnabled(false).setVisible(false);     } else {         menuItemMapView.setEnabled(false).setVisible(false);         menuItemmenuItemSatelliteView.setEnabled(true).setVisible(true);     }      return super.onPrepareOptionsMenu(menu); } 

Here's the onOptionsItemSelected

@Override public boolean onOptionsItemSelected(final MenuItem menuItem) {     switch (menuItem.getItemId()) {         case R.id.men_mapview:             mapView.setSatellite(false);             mapView.setStreetView(true);             mapView.invalidate();              invalidateOptionsMenu(); // This works on Android 3.x devices only             return true;         case R.id.men_satelliteview:             mapView.setSatellite(true);             mapView.setStreetView(false);             mapView.invalidate();              invalidateOptionsMenu(); // This works on Android 3.x devices only             return true;     }      return super.onOptionsItemSelected(menuItem); } 

EDIT: If I add invalidateOptionsMenu this works on Android 3.x apps but crashes on Android 2.x devices because of a missing method. What's the recommended way to do it right?

Answer 1

My method of choice is to create a helper class. For example:

class VersionHelper {     static void refreshActionBarMenu(Activity activity)     {         activity.invalidateOptionsMenu();     } } 

Now in your code above, replace invalidateOptionsMenu(); with:

if (Build.VERSION.SDK_INT >= 11) {     VersionHelper.refreshActionBarMenu(this); } 

Credit for this method goes to CommonsWare (search for HoneycombHelper, and check out his books - highly recommended)

Answer 2

Thanks to the accepted answer. I am using ActionBarActivity. in this class you can use

supportInvalidateOptionsMenu();