Saturday 16 February 2013

android.os.NetworkOnMainThreadException in android

Hello Droid Guys,

Yesterday , I found a strange issue, my application is running fine on most of
the android devices. But when I run the same application on Samsung S-3, S2,
Samsung Galaxy Duos it will be crashed and give me the error


Caused by: android.os.NetworkOnMainThreadException
10-30 15:07:35.341: E/AndroidRuntime(732):  at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(

In my application basically I am showing a alert dialog with an logout button and on click of logout
button I am calling the service. This functionality is not working on above few device
and crashes every time on clickinng the logout button .

After spending a lot of time on it I came to know that on device api version below 9 we 
can call or write  network call in Main UI Thread but above api version 9 it gives error
android.os.NetworkOnMainThreadException. This is happening my  case.

There are Two way to fix this Issue:
    1.Instead of writing network call in Main UI Thread use Async Task.
    2.Add below code into your activity class inside onCreate() method just  after the 

     if( Build.VERSION.SDK_INT >= 9){
            StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();

Hoping , this will helps you.
Enjoy Coding :)

Mukesh Kumar

Hi Guys I am from Delhi working as Web/Mobile Application Developer(Android Developer), also have knowledge of Roboelctric and Mockito ,android test driven development... Blogging has been my passion and I think blogging is one of the powerful medium to share knowledge and ideas....


  1. Hi Mukesh,
    All the best for your blog.

    This is not good idea. Your solution should avoid executing network operations like webservices calls should be done in a separate thread.
    AsyncTask provides a easy to use facility. You can as well write custom thread using java and without using much using android threads.

  2. Thanks for your suggestion.
    Yes , you right, thats why I mention the two way and the first one is via using AsyncTask.

    Also you notice that Android 3.0 (Honeycomb) StrictMode is configured to crash with a NetworkOnMainThreadException exception, if network is accessed in the user interface thread.

    Also , when I am showing an alert dialog on main thread(no nerwork call) this exception will occur, So for that I prefer to use StrictMode policy.

  3. Also ,this helps you in making network access independent from background processing.

  4. Hi Mukesh you can help me ? i need your help, please give me your email.... i want ask you something and solved my problem

  5. Hello Ardian,
    My email id is



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