app crash when ListView is empty | ListView dont show content if i use ArrayList<>()

Question

My ListView crush when its empty. I want to show on it EmptyView. I've found few 'solutions' but they didnt helped me.. I've tried ' List valueList = new ArrayList<>(); ' and with that setEmptyView working, but when ListView shouldn't be empty I only saw setEmptyView... Please help me to fix it, here is my code:

Adapter:

List<User> valueList = new ArrayList<>();

Here I've got error without ArrayList:

@Override
public int getCount()
{
    return this.valueList.size();
}

Activity:

 @Override
    protected void onPostExecute(Void result)
    {
        progressBar.setVisibility(View.GONE);
        ListView.setVisibility(View.VISIBLE);
        ListAdapterClass adapter = new ListAdapterClass(studentList, context);
        if(adapter!=null && !adapter.isEmpty()) {

            ListView.setAdapter(adapter);
        } else {

            MessagesListView.setEmptyView(findViewById(R.id.tv_no_result));
        }
     }

ERROR (without ArrayList)

java.lang.nullpointerexception: attemp to invoke interface method 'int java.util.List.size()' on a null object reference

have you initialised studentList =new ArrayList(); ? – Milan Pansuriya Jun 19 '18 at 09:40 — Milan Pansuriya, Jun 19 '18 at 09:40

score 2 · Accepted Answer · edited Jun 19 '18 at 09:49

2

Try this

@Override
public int getCount()
{
    return this.valueList != null ?  this.valueList.size() : 0;
}

edited Jun 19 '18 at 09:49

AskNilesh

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answered Jun 19 '18 at 09:39

GianhTran

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1

Thanks, its working now :) – Master Jun 19 '18 at 09:44
1

nice to help you – GianhTran Jun 19 '18 at 09:45

app crash when ListView is empty | ListView dont show content if i use ArrayList<>()

1 Answers1