Android, ListView IllegalStateException: “The content of the adapter has changed but ListView did not receive a notification”

Question

What I want to do: run a background thread which calculates ListView contents and update ListView partially, while results are calculated.

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Answer 1

Several days ago I met the same problem and causes several thousands of crash per day, about 0.1% of users meet this situation. I tried setVisibility(GONE/VISIBLE) and requestLayout(), but crash count only decreases a little.

And I finally solved it. Nothing with setVisibility(GONE/VISIBLE). Nothing with requestLayout().

Finally I found the reason is I used a Handler to call notifyDataSetChanged() after update data, which may lead to a sort of:

1. Updates data to a model object(I call it a DataSource)
2. User touches listview(which may call checkForTap()/onTouchEvent() and finally calls layoutChildren() )
3. Adapter gets data from model object and call notifyDataSetChanged() and update views

And I made another mistake that in getCount(), getItem() and getView(), I directly use fields in DataSource, rather than copy them to the adapter. So finally it crashes when:

1. Adapter updates data which last response gives
2. When next response back, DataSource updates data, which causes item count change
3. User touches listview, which may be a tap or a move or flip
4. getCount() and getView() is called, and listview finds data is not consistent, and throws exceptions like java.lang.IllegalStateException: The content of the adapter has changed but.... Another common exception is an IndexOutOfBoundException if you use header/footer in ListView.

So solution is easy, I just copy data to adapter from my DataSource when my Handler triggers adapter to get data and calls notifyDataSetChanged(). The crash now never happens again.