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Problem with global variables

Alix Ollivier
Ranch Hand

Joined: Jun 04, 2012
Posts: 71

I am trying to rewrite a tutorial for slick2d in my own way, but I've met a block. I want to use this code in a void method, while sheet is declared in another class. Is this possible? It says sheet cannot be resolved. I'm on Eclipse. Thanks in advance.

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Jesper de Jong
Java Cowboy
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Joined: Aug 16, 2005
Posts: 15083

You'll need to pass sheet to your method. Methods can't automatically see member variables defined in other classes.

Maybe this is an indication that you should be thinking more about the design of your classes. Think about which classes you have, and which methods belong in which classes.

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Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46356
That isn’t a global variable. It is a private field in another class. You should avoid global variables like the plague, but if you are trying to get a field from another class, you should reconsider your design.
It might be appropriate to give that other class a getSheet() method, or getSpritesFromSheet(), but I don’t know enough about your application to tell that sort of thing. Don’t give the field more visibility in order to placate the compiler.
Alix Ollivier
Ranch Hand

Joined: Jun 04, 2012
Posts: 71

sheet is a SpriteSheet, a .png with many sprites on it. I want to only load one, to make my game load faster and to keep all the assets in one location. Each entity that I will make hopefully will have an public void init() method in which the class initializes all of the variables and assets needed. The method below allows my player class to initialize where his sprites are.
I agree. Here's the link:
subject: Problem with global variables
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