Onclick back button the application stops

Question

I have one problem regarding my app,when i click back button my application is getting finish.i need to prevent it.How could i make it .

@Override
public void onBackPressed() {
   Log.d("CDA", "onBackPressed Called");
   Intent setIntent = new Intent(Intent.ACTION_MAIN);

   startActivity(setIntent);
}

I have tried something like this.But its not working .Actually what i need is when i will click back button ,the application should not finish it should run in background.can anybody help me out.@Thanks

what does mean by 'should run in background'.. is there any special codes what what you want to do? — Pankaj Kumar, May 13 '13 at 07:31
what the mean `run in background`, ? either you can disable back button or don't finish activity before you call new activity in stack — Chintan Khetiya, May 13 '13 at 07:31
@Waqas no it is not showing error/crash, but i need that on click back button the application should not finish ,it should always run in background — , May 13 '13 at 07:32
Use a service if you want your app to keep running in the background. — Vikram Gupta, May 13 '13 at 07:32
@PankajKumar run in background means the activity should not close it should keep working — , May 13 '13 at 07:33
An activity is a single, focused thing that the user can do. You need to create a service to do the background work. — Tarun, May 13 '13 at 07:34
take a look at these: http://developer.android.com/reference/android/app/Service.html and http://www.vogella.com/articles/AndroidServices/article.html — Vikram Gupta, May 13 '13 at 07:36
http://stackoverflow.com/questions/4779954/disable-back-button-in-android @Raghunandan is it okay ? i am using this and disable as per needs — Chintan Khetiya, May 13 '13 at 07:37
@vickey is there any FLAG that will keep the application on running in background — , May 13 '13 at 07:39
No there isn't. There is an Activty method moveTaskToBack(boolean nonRoot). Have a look at that. Although I strongly urge you to use a service. — Vikram Gupta, May 13 '13 at 07:41
You create a service just like an activity and bind it to your main activity. Once started, Services are designed to run in the background. Click on the following links to understand services: developer.android.com/reference/android/app/Service.html and vogella.com/articles/AndroidServices/article.html. — Vikram Gupta, May 13 '13 at 07:46

score 2 · Accepted Answer · answered May 13 '13 at 07:32

2

Try doing it like this:

@Override
public void onBackPressed() {
    Log.d("CDA", "onBackPressed Called");
    Intent intent = new Intent();
    intent.setAction(Intent.ACTION_MAIN);
    intent.addCategory(Intent.CATEGORY_HOME);

    startActivity(intent);
}

By doing this, your activity will not be destroyed (i.e. onDestroy will not be raised). But also, there's no guarantee that Android will preserve your activity for long.

In case, you are running a process that you want to keep on running even in background, then I would suggest you to go for Service or IntentService.

answered May 13 '13 at 07:32

waqaslam

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This is same as pressing the home button but it does not guarantee that the app will keep running seamlessly. – Vikram Gupta May 13 '13 at 07:34
Thanks ,using the above code does the activity will never close – May 13 '13 at 07:34
@vickey how could i supposed to make it – May 13 '13 at 07:35
@vickey I think she didnt want `onDestroy` to be raised on her activity even when back-key is pressed. – waqaslam May 13 '13 at 07:36
@Waqas right and i need that the application also still work in minimizing – May 13 '13 at 07:37
@priya2134412 then go for `Service` or `IntentService` – waqaslam May 13 '13 at 07:38
@Waqas Is there any FLAG intent that will perform that service – May 13 '13 at 07:41
No! you need to create your own class that extends Service. Later, use threads to perform your desired task(s) in that service – waqaslam May 13 '13 at 07:52
@Waqas thanks it is working fine..shall i continue with this code or add service – May 13 '13 at 07:57
In the long run, I would suggest you to make use of Service because its the way to perform background tasks – waqaslam May 13 '13 at 08:06

score 2 · Answer 2 · answered May 13 '13 at 07:34

What do you mean by "it should run in background"? Why would you want that? If the user wants to keep the app opened, he can use the home button and the app won't be closed, if he presses the back button he wants to close the app. If want to have something that is still running even after the user closes the application you should take a look at Service http://developer.android.com/reference/android/app/Service.html, this will continue running even after the user closes the app

Onclick back button the application stops

2 Answers2