Question

In my action bar I have 2 menu items:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:id="@+id/refresh"
          android:title="Refresh"
          android:icon="@drawable/refresh"
          android:showAsAction="ifRoom" >
    </item>
    <item android:id="@+id/back"
          android:title="Back"
          android:icon="@drawable/back"
          android:showAsAction="ifRoom" >
    </item>
</menu>

I’m trying to turn “invisible” my menu item “Refresh”, when I call the function refreshinvisible(), the Refresh item goes away, but now the action bar shows two “back” items… Why? (I’m using SherlockActionBar)

My refreshinvisible() function:

public void refreshinvisible(){
        MenuItem item = menu.findItem(R.id.refresh);
        item.setVisible(false);
}  

Anyone know how to proceed?

Answer 1

There is a method called onPrepareOptionsMenu() which is called every time right before the menu is shown, i.e. before onCreateOptionsMenu() is called. You can use the activity’s invalidateOptionsMenu() method to trigger a redraw of the options menu.
Hence, you can easily re-create your menu taking into account certain conditions.

Here’s some code. Define two booleans as fields of your class, for example:

private boolean showRefresh;
private boolean showBack;

Override the onPrepareOptionsMenu() method and set the menu item’s visbility depending on the respective boolean:

@Override
public boolean onPrepareOptionsMenu( Menu menu ) {

    super.onPrepareOptionsMenu( menu );

    menu.findItem( R.id.refresh ).setVisible( showRefresh );
    menu.findItem( R.id.back ).setVisible( showBack );

    return true;
}

No every time you want to change the visibility of a certain menu item, set the respective boolean accordingly and call the invalidateOptionsMenu() method.