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ArrayList is initialized, but still returns NullPointerException when trying .add(string) method

EDIT: i was totally wrong. This sentence is wrong: You cannot set an adapter with an empty ArrayList, even if u initialized it before. The adapter will find no value and throw the exception. so my solution is useless. I will delete it in 2 days if it's useless. I did notice which was the problem later, but someone else already answered. :) EDIT END

You cannot set an adapter with an empty ArrayList, even if u initialized it before. The adapter will find no value and throw the exception.

Try this:

public class ShowTalkActivity extends
Activity implements OnClickListener {

private ListView listView;
ArrayList<String> messages;
ArrayAdapter<String> adapter;

protected void onCreate(Bundle savedInstanceState)


    Intent intent = getIntent();
    String selected =

    listView = (ListView)
    messages = new ArrayList<String>();
    //adapter = new
ArrayAdapter<String>(this,R.layout.message_list_row,, messages);



public void onClick(View view) {
    if (adapter == null) {
      adapter = new
ArrayAdapter<String>(this,R.layout.message_list_row,, messages);         
    else {

Hope i understood your needings.

Categories : Java

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