How can I alter a MenuItem on the Options Menu on Android?

Question

I have an Options Menu on my Activity with an MenuItem \"Start\". When this MenuItem is selected I would like to alter the Menu so it

Answer 1

Flygenring answer is correct, but menu.findItem() is laggy and calling it within onPrepareOptionsMenu(Menu menu) produces bad user experience. It's better to get MenuItem object once while creating menu, and then just call setVisible each time menu occures on screen:

    MenuItem mDynamicMenuItem;

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        // Get dynamic menu item
        mDynamicMenuItem = menu.findItem(R.id.menu_item);
        return true;
    }

    // Prepare the Screen's standard options menu to be displayed. This is called right 
    // before the menu is shown, every time it is shown. You can use this method to
    // efficiently enable/disable items or otherwise dynamically modify the contents.
    @Override
    public boolean onPrepareOptionsMenu(Menu menu) {
        super.onPrepareOptionsMenu(menu);
        // Here is just a good place to update item
        mDynamicMenuItem.setVisible(isVisible);
        return true;
    }