Toolbar.inflateMenu seems to do nothing

If you are calling setSupportActionBar() you don’t need to use toolbar.inflateMenu() because the Toolbar is acting as your ActionBar. All menu related callbacks are via the default ones. The only time you need to call toolbar.inflateMenu() is when you are using the Toolbar as a standalone widget. In this case you will also have to handle menu item click events via

toolbar.setOnMenuItemClickListener(
        new Toolbar.OnMenuItemClickListener() {
            @Override
            public boolean onMenuItemClick(MenuItem item) {
                // Handle menu item click event
                return true;
            }
});