MainActivity.java

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu,menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.action_add_task:
            Log.d("MainActivity","Add a new task");
            return true;

        default:
            return false;
    }
}