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Index › Programming Questions & Help › Syntax Questions › Dynamic object creation
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Dynamic object creation (Read 438 times)
tommudd
Dynamic object creation
Aug 10th, 2008, 2:52am  
Hello. does anyone know how I could create many instances of an object in a for loop?

for example, instead of:

myObject new_object1 = new myObject();
myObject new_object2 = new myObject();
myObject new_object3 = .....

I want to do something like

String[] object_names = new String[100];

for (int i=0; i<10; i++) {
 object_names[i] = "new_object"+i;
}

for (int i=0; i<10; i++) {
 myObject object_names[i] = new myObject();
}

This array approach doesn't seem to be working, maybe I don't have the syntax quite right? I get the error 'expecting SEMI, found 'object_names' for the line inside the second for loop (myObject object_names[i] = new myObject();).

Can anyone help??

Thanks

Tom
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JohnG
Re: Dynamic object creation
Reply #1 - Aug 10th, 2008, 12:28pm  
he way you do it is:

Code:
myObject[] objects=new myObject[100];
for(int i=0;i<100;i++)
{
  objects[i]=new myObject();
}


You can't (easily) refer to objects by a string containing their name like you can in certain other languages.
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tommudd
Re: Dynamic object creation
Reply #2 - Aug 10th, 2008, 2:32pm  
Thanks, just one more thing though...

I'm having trouble with where exactly I can use a for loop to declare the array of objects. If I use a for loop before void setup() then I get 'unexpected token: void', If I use it within setup, the objects[] array isn't recognised in'void draw()': i get the message 'no accessible field named "objects" was found in type "Temporary_506_9332".

Any suggestions
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antiplastik
Re: Dynamic object creation
Reply #3 - Aug 10th, 2008, 4:25pm  
Code:
myObject[] objects;  // declare objects as global variable

void setup() {
  objects = new myObject[100];
  for(int i=0;i<100;i++) {
    objects[i] = new myObject();
  }
}

void draw() {
  // you can access objects here since it's a global variable
}
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WWW  
tommudd
Re: Dynamic object creation
Reply #4 - Aug 10th, 2008, 11:58pm  
Excellent, thanks very much
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