How can I refresh the ActionBar when onPrepareOptionsMenu switched menu entries?
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?
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)
Thanks to the accepted answer. I am using ActionBarActivity. in this class you can use
supportInvalidateOptionsMenu();
Use
ActivityCompat.invalidateOptionsMenu(Activity activity)
from the compatibility library.
See: https://stackoverflow.com/a/14748687/435855
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