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Why and when to unregister Android content

I am developing an Android application and working with content watchers for the first time. So I read a lot of tutorials and realized why it is provided and how to use it.

Now I read these blog posts which

Do not forget to unregister observers

So, I can’t understand if I want to register ContentObserver, what could be the situation in which I should cancel it.

If the goal of the observers is fulfilled, then this is normal, we can cancel the registration. But I have to watch until the user uninstalls the application, then why am I going to unregister the observer.

Here is the url of this blog

http://www.grokkingandroid.com/use-contentobserver-to-listen-to-changes/

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4 answers

Imagine you have an application that allows you to use the friend list screen created with FriendListActivity. Now, to create a user interface for this action, you read the data from the database and create your user interface.

Now imagine that you also have a service that runs in the background and synchronizes this database with a remote database using web services.

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Activity Life Cycle

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onResume(), onPause().

, .it observe memory leak.

  @override

    public void onDestroy()
    {

getContentResolver().
      unregisterContentObserver(yourObserver);

    }


 @override

    public void onPause()
    {
    getContentResolver().
  unregisterContentObserver(yourObserver);

    }
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:

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, Activity , - onPause. onPause , Activity.

Activities: http://developer.android.com/reference/android/app/Activity.html#ActivityLifecycle

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