DOInBackground ERROR

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DOInBackground ERROR

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#1 by (2 votes)
#2 by (0 votes)

0

This function is giving me the following error:

            @Override
            protected Boolean doInBackground(Void... args0) {
                updateJSONdata();
                return null;

            }

android

asked by anonymous 30.06.2014 / 12:17

2 answers

Change variable in a Task Problems with programming logic [closed]

score 2 · Answer 1

I believe that within updateJSONdata() you are calling Toast . This is not allowed because Toast can only be called on the main thread, which is responsible for screen updates, whereas the doInBackground() method executes on a secondary thread, which is not allowed to refresh the screen. >

This can also happen if you are instantiating a Handler within updateJSONdata() . Handler is able to execute code on the main thread and therefore call Toast . If this is the case, one way to correct the error would be to instantiate the Handler passing Looper.getMainLooper() , that is:

new Handler(Looper.getMainLooper())

But since you are using AsyncTask , you should not instantiate Handler , but instead execute statements on the main thread using the AsyncTask API, ie overwriting and calling methods that AsyncTask itself to refresh the screen during or after running doInBackground() .

These methods are:

/ li>
publishProgress() or doInBackground() after running publishProgress() . Unlike the latter, which runs on a separate thread, these methods I've run run on the main thread (making use of a publishProgress() internally) and are the appropriate methods for you to overwrite and refresh the screen.

I hope it's clear, any questions are just a comment.

score 0 · Answer 2

Put the implementation of your updateJSONdata(); function to facilitate the help.

At first, inside threads that are not runOnUiThread you should not manipulate views of the main thread (Activity)