Having trouble with ArrayList cant find an answer

Processing Beginners
1

I am getting "The function hits() does not expect parameters


for (int i=bullet.size()-1;i>0;i--){
    b.display();
    b.update(); 
    for (int j=asteroid.size()-1;j>0;j--){
      if(bullet.get(i).hits(asteroid.get(i)))){ 

      }//end bullet.hits(asteroid) loop
    }//end for loop
}

The function in my bullet class;



void hits(){
      float d = dist(pos.x,pos.y,a.pos.x,a.pos.y);
      if( d<a.r){
        print("hit");
      }
2

and

does not fit!
you should pass the asteroids parameter.

3

void hits(){

must be

void hits(Bullet a){

Within the brackets you define the parameters

4

so if (asteroids.get(i)) is an ArrayList of PVectors and this is written globally, I have written the hits() in the bullet class and checking the distance between the bullet.x and bullet.y to the asteroid.x and asteroid.y.

If I add void hits(PVector pos){ which would be the bullet pvector in the class, i then get hits() expecting paramenters hits(PVector) but its an array of PVectors

5

We are talking about this line

Depending on what asteroids contains,
In void hits say PVector or Bullet as parameter

6

Parameters must match

7

To summarize: here is a function:

void hi(){
  println("hi");
}

Based on the empty () in its fist line, it does not expect parameters. You can call it like this:
hi();
…but not like this:
hi("hello");

Here is another function:

void word(String wrd){
  println(wrd);
}

It does expect parameters – the parameter wrd that appears in the () in the first line. You can call it like this:
word("hello");
…but not like this:
word();

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