Toast.makeText(getApplicationContext(), R.string.hello_world, Toast.LENGTH_LONG)
calls
Toast.makeText(Context, int, int)
and it is "translated" like
public static Toast makeText(Context context, int resId, int duration)
throws Resources.NotFoundException {
return makeText(context, context.getResources().getText(resId), duration);
}
all in all it is equal to your first makeText