All elements change in Arraylist - Processing - arrays

Question

My program is a zombie survival game, set in a 2d array of blocks.
I use an arraylist - my first attempt - to store the zombies, and each in tern "checks" if there is a block above, below and around it, to detect it's movement.
I'll post the relevant code here, and upload the sketch folder separately.
ArrayList zombies;
void setup() {
zombies = new ArrayList();
}
void draw() {
for (int i = 0; i < zombies.size(); i++) {
Zombie zombie = (Zombie) zombies.get(i);
zombie.draw();
}
}
void keyPressed() {
if (key == 'z') {
zombies.add(new Zombie());
}
}
class Zombie
{
int posX = 20;
int posY = 10;
boolean fall;
boolean playerOnBlock;
Zombie() {
posX = 10;
posY = 590;
fall = false;
}
void draw() {
grid.blockCheck(posX, posY, 2);
fill(0, 255, 0);
rect(posX, posY, 10, 10);
}
void fall() {
posY += 5;
println("zombiefall"+posY);
}
void move(boolean left, boolean right, boolean above) {
if (left == true && player.playerX < posX) {
posX -= 1;
}
if (right == true && player.playerX > posX) {
posX += 1;
}
}
}
class Grid {
void blockCheck(int x, int y, int e) {
for (int i = 0; i < l; i++)
for (int j = 0; j < h; j++)
{
grid[i][j].aroundMe (x, y, i, j, e);
}
}
}
class Block {
void aroundMe(int _x, int _y, int _i, int _j, int entity) {
int pGX = _x/10;
int pGY = _y/10;
if (entity == 1) {
if (pGY+1 == _j && pGX == _i && state == 4) {
player.fall();
}
if (pGX == _i && pGX-1 <= _i && _y == posY && state == 4) {
leftOfMe = true;
}
else
{
leftOfMe = false;
}
if (pGX+1 == _i && _y == posY && state == 4) {
rightOfMe = true;
}
else
{
rightOfMe = false;
}
if (pGY-1 == _j && _x == posX && state ==4) {
aboveOfMe = true;
}
else
{
aboveOfMe = false;
}
player.controls(leftOfMe, rightOfMe, aboveOfMe);
}
if (entity == 2) {
if (pGY+1 == _j && pGX == _i && state == 4) {
for (int i = 0; i < zombies.size(); i++) {
Zombie zombie = (Zombie) zombies.get(i);
zombie.fall();
}
}
if (pGX == _i && pGX-1 <= _i && _y == posY && state == 4) {
ZleftOfMe = true;
}
else
{
ZleftOfMe = false;
}
if (pGX+1 == _i && _y == posY && state == 4) {
ZrightOfMe = true;
}
else
{
ZrightOfMe = false;
}
if (pGY-1 == _j && _x == posX && state ==4) {
ZaboveOfMe = true;
}
else
{
ZaboveOfMe = false;
}
for (int i = 0; i < zombies.size(); i++) {
Zombie zombie = (Zombie) zombies.get(i);
zombie.move(ZleftOfMe, ZrightOfMe, ZaboveOfMe);
}
}
Sketch is here: http://www.mediafire.com/?u5v3117baym846v
I believe the problem lies in specifying which element of an arraylist I am referring to, as I can observe the issues to be:
All "zombies" fall when one detects that it should fall.
Zombie's speed increases with each additional zombie added - somehow treating all the zombie elements as one zombie object?
This might be a similar issue:
All elements of An ArrayList change when a new one is added?
But I've fiddled with my project and I can't seem to get it working still.
Please don't hesitate to ask for more information on my project. I will be with my computer all evening so should be able to reply quickly. Thanks in advance.
Thanks for your help.
I'm using it like this:
ArrayList <Zombie> zombies = new ArrayList <Zombie>();
-------------------------------------------
void setup(){
zombies = new ArrayList();
-------------------------------------------
void draw(){
for (Zombie z:zombies) {
z.draw();
}
}
-------------------------------------------
void keyPressed() {
if (key == 'z') {
for (int i = 0; i< 1; i++) {
zombies.add(new Zombie(i));
}
}
-------------------------------------------
class Zombie
{
int posX = 20;
int posY = 10;
boolean fall;
boolean playerOnBlock;
int z;
Zombie(int _z) {
posX = 10;
posY = 590;
fall = false;
z = _z;
}
void draw() {
grid.blockCheck(posX, posY, 2);
fill(0, 255, 0);
rect(posX, posY, 10, 10);
}
void fall() {
posY += 5;
println("zombiefall"+posY);
}
void move(boolean left, boolean right, boolean above) {
if (left == true && player.playerX < posX) {
posX -= 1;
}
if (right == true && player.playerX > posX) {
posX += 1;
}
}
}

Answer 1

Here is the idea :)
//use generics to keep it simple. Only Zoombies in this list
ArrayList <Zoombie> samp = new ArrayList <Zoombie>();
void setup() {
//a regular for loop to use the i as id
for (int i = 0; i< 100; i++) {
samp.add(new Zoombie(i));
}
//run just once
noLoop();
}
void draw() {
//a enhanced for, no need for use get()
// z will represent each element in the collection
for (Zoombie z:samp) {
z.d();
}
println("done");
}
// a dummy class ;)
class Zoombie {
int id;
Zoombie (int _id)
{
id =_id;
}
void d()
{
println(id);
}
}