How come a "pre-defined" function cant be put inside of a class?

Meowsterr

I tried putting void mousePressed inside of a class and it wouldn't work, but then when I moved it outside of the class it worked. How come it only worked when outside of the class?

GoToLoop

mousePressed() is a Processing PApplet's callback function. Just like setup() & draw() are too.
If we place any of them inside another class, the PApplet class won't be able to find them!
Unless we registerMethod() them btW: :P
http://forum.Processing.org/two/discussions/tagged?Tag=registermethod()

asimes

Place mousePressed() in the global scope and have it call your class' method

Here is an example:

Foo[] foo;
int counter = 0;

void setup() {
  size(100, 100);
  foo = new Foo[3];
  for (int i = 0; i < 3; i++)
    foo[i] = new Foo(i);
}

void draw() {
}

void mousePressed() {
  foo[counter].sayHello();
  counter = (counter + 1) % 3;
}

class Foo {
  int index;

  Foo(int index) {
    this.index = index;
  }

  void sayHello() {
    println("Hello from: " + index);
  }
}

Chrisir

mousePressed is a build-in function that can obly be seen by processing when it's outside the classes. So when it's on a global level.

As been said you can call the hidden mousePressed (it can have any name) that's inside the class from the real in-build mousePressed (outside the class):

void mousePressed(){ 

      myObject.mousePressed();

Same goes for mouseClicked etc etc