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gregory stocker
gregory stocker
3,520 Points

Why are things like listeners called inside the OnCreate method? Isn`t OnCreate only called when the app first launches?

Is OnCreate continually called or is it just called once? How does it track a listener if it is only called when the app first opens up? Is it like a while loop that keeps checking? The way I think of it it would only work if you had an onClickListener setup and you clicked it right as it was created, but that`s obviously not the case.. What am I missing about how the android lifecycle works. When the app is running what state is it in that is constantly checking things? I hope this question makes sense thanks anyone in advance.

1 Answer

It is only called once when you start the application. It doesn't track the listener. The listener is an object that is created when the application starts if it is under the OnCreate method. A listener is not a loop, it waits for an input from a user. The app doesn't constantly check things. It waits for the users to do something with it. A user can pause, stop, destroy, restart an application, or continue using it. These are all part of the Android lifecycle. I suggest that you read this article http://developer.android.com/training/basics/activity-lifecycle/starting.html