java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification.

Question

I would like to put a large number of add delete calculation work on the worker thread, notifyDataSetChanged work on the ui thread. On the basis of it to avoid the java.lang.IllegalStateException. Exception as follows: java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread. Make sure your adapter calls notifyDataSetChanged() when its content changes.

code shorthand such as:

new Thread(){
            @Override
            public void run() {
                for(int i=0; i<5000; i++){
                    mDatas.add(i);
                }
                mActivity.runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        mAdapter.notifyDataSetChanged();
                    }
                });
            }
        }.start();

I am searching for a long time on net. But no use. Please help or try to give some ideas how to achieve this.

Possible duplicate of http://stackoverflow.com/questions/3132021/android-listview-illegalstateexception-the-content-of-the-adapter-has-changed — Jay Rathod, Jan 12 '17 at 10:41
Also you can try adding data and *notifyDataSetChanged* both inside *UI thread*. — Jay Rathod, Jan 12 '17 at 10:43
@jaydroider thanks , I read the question but did not feel the perfect answer. — yulongzou, Jan 12 '17 at 10:45
@jaydroider If it is large data will affect the performance. — yulongzou, Jan 12 '17 at 10:49
@quick learner Thank you for pointing out the problem with my code. And I focus on the above problems. — yulongzou, Jan 12 '17 at 11:02
i posted my answer, if hope it works, Do upvote if its working — Quick learner, Jan 12 '17 at 11:08

score 0 · Answer 1 · answered Jan 12 '17 at 10:44

0

You are adding items to ArrayList in non-UI thread and calling notifyDataSetChanged on the UI Thread

new Thread(){
            @Override
            public void run() {

                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        for(int i=0; i<5000; i++){
                            mDatas.add(i);
                        }
                        mAdapter.notifyDataSetChanged();
                    }
                });
            }
        }.start();

answered Jan 12 '17 at 10:44

Sadiq Md Asif

882
6
18

A large number of operations in the UI thread will have performance problems such as UI card Dayton. – yulongzou Jan 12 '17 at 10:58
are you calling `mAdapter.notifyDataSetChanged()` from any background service ? if its from activity/fragment you don't need the whole runOnUiThread thing – Sadiq Md Asif Jan 12 '17 at 11:07
it's from dialog calling mAdapter.notifyDataSetChanged(). – yulongzou Jan 12 '17 at 11:12

score 0 · Answer 2 · answered Jan 12 '17 at 11:08

0

Try this

Check if mActivity is null or not before calling runOnUi thread

 new Thread(){
                @Override
                public void run() {
                    for(int i=0; i<5000; i++){
                        mDatas.add(i);
                    }
                  if(mActivity!=null){
                    mActivity.runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            mAdapter.notifyDataSetChanged();
                        }
                    });
                   }
                }
        }.start();

answered Jan 12 '17 at 11:08

Quick learner

10,632
4
45
55

Thank you for pointing out the problem with my code. And I focus on the above problems. – yulongzou Jan 12 '17 at 11:13
sorry, I hope that I can upvote for you, but my honor is less than fifteen. – yulongzou Jan 12 '17 at 11:17

score 0 · Accepted Answer · answered Jan 12 '17 at 11:20

There are two solutions to overcome with it.

1) Use AsyncTask and update your adapter in onPostExecute() method.

@override
protected void onPostExecute(String result) {
  mAdapter.notifyDataSetChanged();
}

2) Use Handler with Thread to register message and in handleMessage() update your adapter.

    new Thread(){
        @Override
        public void run() {

                  handler.sendEmptyMessage(0);
                }
            });
        }
    }.start();

 Handler handler = new Handler(new Handler.Callback() {
        @Override
        public boolean handleMessage(Message message) {
            mAdapter.notifyDataSetChanged();
            return false;
        }
    });

You may not have read my question, no matter how or thank you — yulongzou, Jan 12 '17 at 11:29

java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification.

3 Answers3