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problems with displaying..

 
Savanna Ray
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Hello,

I'm trying to display a 3 x 3 grid made up of an array of 9 individual cell objects. I created two classes, one for each cell, and one for the whole board. So far, I can only display the board 'border'. When I try to invoke the method to draw each cell from the Board class, i get a null pointer exception error within the black dos window for some reason?? Would anyone care to take a look and give a little feedback? I would really appreciate it.

Here's the code:



Thanks
from BC
 
Julien Martin
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Hello Savanna,

Your problem lies in the Board constructor. You have instanciated TWO arrays of cells. One here:



and a second here:



The first one is an instance variable and the second one a local variable.

The one you are using in the drawBoard method is the instance variable which contains null values hence the null pointer exception you get.

Change your Board class to that:



Tell me if that helped,

Julien.
 
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