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POWhy AsyncTask behaves differently if declared as inner class of an Activity or on a separate file?
 

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  1. POWhy AsyncTask behaves differently if declared as inner class of an Activity or on a separate file?
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    <p>I'm using an ORM for Android called <a href="https://github.com/satyan/sugar/wiki/Getting-Started" rel="nofollow">Sugar</a> to persist my models on the database and I'm using it inside my AsyncTask.</p> <p>Here is its declaration:</p> <pre><code>public class LoginTask extends AsyncTask&lt;Object, Integer, String&gt; { private Context context; private ProgressDialog progressDialog; public LoginTask(Context context) { this.context = context; } @Override protected void onPreExecute() { progressDialog = new ProgressDialog(context) { { setMessage("Authenticating..."); setTitle("Login"); setCancelable(false); setIndeterminate(true); show(); } }; } @Override protected String doInBackground(Object... params) { String email = (String) params[0]; String password = (String) params[1]; try { User user = LoginWebService.loginUser(email, password, context); user.save(); } catch (CommunicationException e) { e.printStackTrace(); return e.getMessage(); } return null; } @Override protected void onPostExecute(final String result) { progressDialog.dismiss(); } } </code></pre> <p>The line <strong>user.save()</strong> above, that saves the user model in the db, is the one that causes the exception. The strange thing is that if I declare the task above as an inner class from the activity, it works fine, but if I declare the task on a separate file, it throws this exception:</p> <pre><code>E/AndroidRuntime(17172): at com.app.task.LoginTask.doInBackground(LoginTask.java:47) E/AndroidRuntime(17172): at com.app.task.LoginTask.doInBackground(LoginTask.java:1) E/AndroidRuntime(17172): at android.os.AsyncTask$2.call(AsyncTask.java:264) E/AndroidRuntime(17172): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305) E/AndroidRuntime(17172): ... 5 more E/AndroidRuntime(17172): Caused by: java.lang.RuntimeException: Cant create handler inside thread that has not called Looper.prepare() </code></pre> <p>I can't see what makes the difference as I can't see any sense on this.</p>
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    1. USkaneda
    1. USkaneda
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      1. VTUpMod
    1. COcan you post the User.save() method source code?
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      1. USFoamyGuy
    2. CO@Tim, That part of the code is from the ORM, but I can point you to the source code [here](https://github.com/satyan/sugar/blob/master/src/com/orm/SugarRecord.java). You can look after the method save in there.
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      1. USkaneda
    3. CO**"Cant create handler inside thread that has not called Looper.prepare()"** - Agreed with the answer from 10s - this is the sort of error you would see if trying to manipulate an object on the main/UI thread from another thread (such as that of `doInBackground(...)` of an `AsyncTask`). Not sure how this would work as an inner class (as you claim) - it should throw the same exception. Why don't you just return `user` from `doInBackground(...)` and have `onPostExecute(...)` call `user.save()`?
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      1. USSquonk
 

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