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Index › Programming Questions & Help › Programs › Global array variable
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Global array variable ? (Read 436 times)
alphachapmtl
Global array variable ?
Nov 8th, 2007, 5:40pm  
What is wrong with this? (I get java.lang.NullPointerException)
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int[] kk; //<<< I want kk[] to be available globally

void setup() {
 size(120,120);
 noLoop();
 //
 int[] kk={
   11,22,33  }; //<<< kk[] setup at runtime
}//setup()

void draw() {
 print(kk[1]); //<<< kk not available here ???
}//draw()
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JohnG
Re: Global array variable ?
Reply #1 - Nov 8th, 2007, 7:06pm  
You're setting up two different arrays called kk

Code:
 int[] kk; //<-- this is a global kk
 
void setup() {
  size(120,120);
  noLoop();
 
//  int[] kk={ // <-- this is a LOCAL kk
//    11,22,33};
  //what you really want is:

  kk=new int[]{11,22,33};
  //if you specify a type, it creates a new, different variable.
}
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antiplastik
Re: Global array variable ?
Reply #2 - Nov 8th, 2007, 7:15pm  
Exactly : variables declared in a method can only be adressed within this method, otherwise the compiler throws a null exception. This is the concept of scope. To setup a global variable, declare it outside of any method.
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