Static array with custom class?

Question

So I thought I had figured out static variables until I ran into this problem:

Works:

 //ScriptOne
 static var lot = new int[4];
 static function output () {
     var ret = lot[0];
     return ret;
 }

Doesn't work:

 //ScriptOne
 class pig{
     var weight:int=6;
 }
 
 static var lot = new pig[4];
 static function output () {
     var ret = lot[0].weight;
     return ret;
 }
 
 //ScriptTwo
 function Update () {
 Debug.Log(ScriptOne.output());
 }

NullReferenceEception on play

It appears that an array whose type is a custom class cannot be made static. Is there a workaround or a better way to do this that works? I am writing a script that I want to be treated as a library of functions and in this case there should only be one instance of the array at a time so it made sense to make it static. Am I missing something?

Answer 1

Best Answer

Answer by gfr · Nov 02, 2011 at 09:57 AM

You have initialized the array, but not it's contents. For basic types (like ints) that fine, but not for class-types. You need to initialize the array contents once.

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TheAssassin · Nov 02, 2011 at 08:10 PM 0

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Yeah I initialized it. var lot = new lot[] is the same as var lot:lot[] = new lot[4];

I also tried changing a variable using an initialize function that I called in the start of scriptTwo and the results were the same. If you are sure that's whats going on could you post an example?

gfr · Nov 02, 2011 at 09:27 PM 0

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@TheAssassin: I meant actually initializing the contents of the array. For class-types those are references and have to be set to specific instances, otherwise they refence nothing. E.g.:

 for (var i=0; i<lot.length; ++i)
     lot[i] = new pig();

This is the same with non-static arrays.

TheAssassin · Nov 03, 2011 at 12:41 AM 0

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Sorry I was in a hurry and didn't fully look into what you were saying. It works Great thanks!

gfr · Nov 03, 2011 at 01:16 AM 0

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No problem, i guess putting in a code-snippet right away would have been better to avoid misunderstandings.

Static array with custom class?

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