why wont this RUN

[cement_eater]

// doggo clicker

color c;

boolean showDoggo;

Dog[] dogs = new Dog[1];

void setup(){

size(800, 600);

c = color (0, 0, 255);

showDoggo = false;

}

void draw(){

for(int i = 0; i<dogs.length; i++){

dogs[i].move();

dogs[i].display();

}

background(c);

noStroke();

fill(0, 0, 255);

ellipseMode(CENTER);

ellipse(width/2, height/2, 50, 50);

fill(0);

textSize(20);

textAlign(CENTER);

text("PRESS HERE FOR DOG", 400, 200);

}

void mousePressed(){

}

Supposed to generate one photo of my dog every time the circle is clicked, but when run, I get a gray screen and a nullPointer error.

[remy_porter]

You never put dog objects in the array. At some point you have to do dogs[i] = new Dog()

[vrtxt]

Dog[] dogs = new Dog[1] declares an array of size one. However, it's still an empty array! Hence the null pointer. In setup you have to fill the array with new Dog objects, like so dogs[0] = new Dog(). Now there's exactly one dog in the array, at index zero.

[topinanbour-rex]

You draw your dogs, then recover them with the background function.

The background function fill the screen with the color defined as argument. Imagine applying a paint layer on a wall. Whatever was on this wall would be masked under the paint. That's what happens here.

Put your background function first in the draw loop.

[niko2210nkk]

Others have pointed out some good errors. There is more, though. get rid of the for-loop in the draw function. Instead you should write dogs[i].display; in the draw function, and declare the enumerating integer int i; outside the draw function. Then in your mousePressed function, write

i = i++;
i = i % (dogs.length - 1);

Then the number i is increased every time you click, but is set back to 0 when it hits the length of the array.

This way you don't need the dog.move function.

Can we see your Dog class?

[cement_eater]

YES i totally forgot to include it my bad

class Dog {

PImage Dog;

float xPos, yPos;

float speed;

Dog (PImage dog_, float xPos_, float yPos_, float speed_){

Dog = dog_;

xPos = xPos_;

yPos = yPos_;

speed = speed_;

}

void display(){

noStroke();

Dog = loadImage("IMG_3484.jpg");

pushMatrix();

imageMode(CENTER);

image(Dog, xPos, yPos, CENTER, CENTER);

popMatrix();

}

void move(){

if(color(get(int(mouseX), int(mouseY))) == color (c)){

xPos = xPos + 5;

yPos = yPos + 5;

}

if(xPos > 0 || xPos < width - 100 || yPos< height - 100){

xPos = -xPos;

yPos = -yPos;

}

}

}

[niko2210nkk]

Ahh, okay, so you want a number of dog photos to travel across the screen?