How to select the first item in a navigation drawer and open a fragment on application start

Question

I have created MainActivity with NavigationView. When Activity is opened I want to automatically select the first item in the navigation d

Answer 1

in menu.xml remember to mention android:checkable="true" for single item and android:checkableBehavior="single" for a group of items.

then inside NavigationItemSelectedListener use setCheckedItem(R.id.item_id_in_menu) to make it selected.

@Override
    public boolean onNavigationItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()) {

            case R.id.pos_item_pos:
                navigationView.setCheckedItem(R.id.pos_item_pos);
                break;
            case R.id.pos_item_orders:
                navigationView.setCheckedItem(R.id.pos_item_orders);
                break;
            default:
        }
        return true;
    }

And you do not have to do the dirty task of managing the selected item anymore. navigationView manages it by self.