Processing 1.0 - Processing Discourse - How to access an object variable from outside

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Index › Programming Questions & Help › Syntax Questions › How to access an object variable from outside

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How to access an object variable from outside (Read 460 times)

izmir

How to access an object variable from outside
Oct 29^th, 2006, 1:37am

Hi,

I am still a newbie to the 'this.xx' method. I have constructed an array of objects that looks like this:

MyObject [] myObject = new MyObject[9];

I can address each object from the outside by calling up the specific member of the array like this, so I got the connection working:

if(keyPressed) {
if (key == 'q' || key == 'Q') {
myObject[8].r = 100;
}

However, I cannot just contact _any_ of the members in the array - i.e. I would like to do something like this:

if(keyPressed) {
if (key == 'q' || key == 'Q') {
myObject.this.r = 100;
}

I know that the above is not the right way to do it, but I would like to know how to address any of the members in the array of objects - i.e. if a square collides with any of the objects in the array, they should be red.

thanks for looking at this!
izmir

Daniel Shiffman

Re: How to access an object variable from outside
Reply #1 - Oct 29^th, 2006, 1:04am

You can only ever access an element of the array via its index. You can do this individually (as you did):

Code:


myObjects[8].r = 100;

Or you can access all (or some) of the elements of an array with a loop.

Code:


for (int i = 0; i < myObjects.length; i++) {
  myObjects[i].r = 100;
}

If you want to test all of the elements of the array against some condition, you can do this with an if statement inside a loop, i.e.:

Code:


for (int i = 0; i < myObjects.length; i++) {
  if (myObject[i].r > 50) {
    myObjects[i].callSomeMethod();
  }
}

http://www.learningprocessing.com | http://www.shiffman.net | http://itp.nyu.edu

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