Dialog list adapter crashes on NullPointerException

Question

Im trying to adapt list view to an alertDialog, the program crashes on dialog.setAdapter with NullPointerException.

The alertDialog should pop when user is clicking on item in listview.

ArrayAdapter<String> dialogAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, userFunc);
    lv.setAdapter(dialogAdapter);

    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {


            if (position == 0) {


                AlertDialog.Builder alertDialog = new AlertDialog.Builder(ManagerFunctions.this);
                LayoutInflater inflater = getLayoutInflater();
                View convertView = (View) inflater.inflate(R.layout.user_op_list, null);
                alertDialog.setView(convertView);
                alertDialog.setTitle("Choose option");
                lv = (ListView) convertView.findViewById(R.id.lv);

                alertDialog.show();

This line is the one I'm getting error on:

        lv.setAdapter(dialogAdapter);

Add this `lv = (ListView) convertView.findViewById(R.id.listview_id);` top on `ItemClickListener` — Amy, Dec 09 '15 at 11:05

score 0 · Answer 1 · answered Dec 09 '15 at 11:09

got it, I needed to declare my ArrayAdapter as final, because it cannot be accessed from inner classes.

so:

final String[] userFunc = new String[]{"חדש","מחק","ערוך"};
    final ArrayAdapter<String> dialogAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, userFunc);

    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {


            if (position == 0) {


                AlertDialog.Builder alertDialog = new AlertDialog.Builder(ManagerFunctions.this);
                LayoutInflater inflater = getLayoutInflater();
                View convertView = (View) inflater.inflate(R.layout.user_op_list, null);
                alertDialog.setView(convertView);
                alertDialog.setTitle("מה ברצונך לעשות");
                lv = (ListView) convertView.findViewById(R.id.lv);
                lv.setAdapter(dialogAdapter);

                alertDialog.show();

Dialog list adapter crashes on NullPointerException

1 Answers1