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Android Android Lists and Adapters (2015) Lists with RecyclerViews Creating a RecyclerView ViewHolder

Qiyuan Zhang
Qiyuan Zhang
10,581 Points
Posted by Qiyuan Zhang
Qiyuan Zhang
10,581 Points

Why does java.lang.NullPointerException (Look around JavaTester.java line 129) pop up for task 3?

The error message is not providing useful information anyway...

chrisverra
chrisverra
3,760 Points

could you post the code of that line?

I think in general a NulPointerException means that there is a reference variable that points to something that is not there(anymore?)

2 Answers

Qiyuan Zhang
Qiyuan Zhang
10,581 Points
Qiyuan Zhang
Qiyuan Zhang
10,581 Points

Thanks Chris and Michael. I got the problem solved. It's due to one unnecessary keyword "static" when defining class.

Michael Farber
Michael Farber
1,103 Points
Michael Farber
Michael Farber
1,103 Points

Hi Qiyuan, I agree with Chris. This happened to me once when I tried to call the findViewById method before setting the content layout in java. Maybe this is what's wrong with your code. If it's not, post it and we'll be able to help you more specifically:)