make Toast when ListView is empty

Question

I want to reveal a Toast when my listview is empty, I tried this but it doesn't work, I don't understand why:

if (listView == null) {
        Toast.makeText(this, "No slots selected",
                Toast.LENGTH_LONG).show();
    }

I know how Toast work, but my problem is to detect when a listview is empty.

Could anyone help me plz ?

Answer 1

You need to check the list that attached to your ListView (by the adapter). When a List is created you can't check by == null because the variable is already created.

Instead checking the list size, something like this:

adapter.getCount() == 0