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Fragments and Tabs

I have been going through the tutorial and i have noticed something.

when i do


for the login_fragment it works but when i do


the app crashes when it starts at first i thought it was one of those API level problems and went through the forum but couldn't find the solution and noticed that the id's declaration were different in the guide and in my code.

So i am wondering and interesting why am i getting an error when i do @+ and why dose it work when i use the first way to declare an Id ?

1 Answer

Hey Derese! "@android:id/list" means that you are using a predefined android resource id called "list", while "@+id/list" means that you are creating a new id with the name "list".

The reason it crashes when you use the second one is probably because you have something like a ListActivity that requires you to have a ListView with the first id.

From the ListActivity documentation:

To do this, your own view MUST contain a ListView object with the id "@android:id/list"