Here is my updated files:
Once again, Here are the errors I now am getting:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at Bullet/eFrame()
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at Bullet/eFrame()
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at 15SpaceShooter_fla::MainTimeline/checkKeysDown()[15SpaceShooter_fla.MainTimeline::frame3: 136]
If you scroll back to my original post, the Line 52 on Enemy.as is saying that error
Frame Code:
stop();
//these booleans will check which keys are down
var leftDown:Boolean=false;
var upDown:Boolean=false;
var rightDown:Boolean=false;
var downDown:Boolean=false;
//how fast the character will be able to go
var mainSpeed:int=5;
//how much time before allowed to shoot again
var cTime:int=0;
//the time it has to reach in order to be allowed to shoot (in frames)
var cLimit:int=12;
//whether or not the user is allowed to shoot
var shootAllow:Boolean=true;
//how much time before another enemy is made
var enemyTime:int=0;
//how much time needed to make an enemy
//it should be more than the shooting rate
//or else killing all of the enemies would
//be impossible 😮
var enemyLimit:int=16;
//the player's score
var score:int=0;
//this movieclip will hold all of the bullets
var bulletContainer:MovieClip = new MovieClip();
addChild(bulletContainer);
//whether or not the game is over
var gameOver:Boolean=false;
//adding a listener to mcMain that will move the character
playerShip.addEventListener(Event.ENTER_FRAME, moveShip);
function moveShip(event:Event):void {
//checking if the key booleans are true then moving
//the character based on the keys
if (leftDown) {
playerShip.x-=mainSpeed;
}
if (upDown) {
playerShip.y-=mainSpeed;
}
if (rightDown) {
playerShip.x+=mainSpeed;
}
if (downDown) {
playerShip.y+=mainSpeed;
}
//keeping the main character within bounds
if (playerShip.x<=0) {
playerShip.x+=mainSpeed;
}
if (playerShip.y<=0) {
playerShip.y+=mainSpeed;
}
if (playerShip.x>=stage.stageWidth-playerShip.width) {
playerShip.x-=mainSpeed;
}
if (playerShip.y>=stage.stageHeight-playerShip.height) {
playerShip.y-=mainSpeed;
}
//Incrementing the cTime
//checking if cTime has reached the limit yet
if (cTime<cLimit) {
cTime++;
} else {
//if it has, then allow the user to shoot
shootAllow=true;
//and reset cTime
cTime=0;
}
//adding enemies to stage
if (enemyTime<enemyLimit) {
//if time hasn't reached the limit, then just increment
enemyTime++;
} else {
//defining a variable which will hold the new enemy
var newEnemy = new Enemy();
//making the enemy offstage when it is created
newEnemy.y=-1*newEnemy.height;
//making the enemy's x coordinates random
//the "int" function will act the same as Math.floor but a bit faster
newEnemy.x = int(Math.random()*(stage.stageWidth - newEnemy.width));
//then add the enemy to stage
addChild(newEnemy);
//and reset the enemyTime
enemyTime=0;
}
//updating the score text
scoreField.text="Score: "+score;
}
//this listener will listen for down keystrokes
stage.addEventListener(KeyboardEvent.KEY_DOWN, checkKeysDown);
function checkKeysDown(event:KeyboardEvent):void {
//making the booleans true based on the keycode
//WASD Keys or arrow keys
if (event.keyCode==37||event.keyCode==65) {
leftDown=true;
}
if (event.keyCode==38||event.keyCode==87) {
upDown=true;
}
if (event.keyCode==39||event.keyCode==68) {
rightDown=true;
}
if (event.keyCode==40||event.keyCode==83) {
downDown=true;
}
//this listener will listen for keys being released
stage.addEventListener(KeyboardEvent.KEY_UP, checkKeysUp);
function checkKeysUp(event:KeyboardEvent):void{
//making the booleans false based on the keycode
if(event.keyCode == 37 || event.keyCode == 65){
leftDown = false;
}
if(event.keyCode == 38 || event.keyCode == 87){
upDown = false;
}
if(event.keyCode == 39 || event.keyCode == 68){
rightDown = false;
}
if(event.keyCode == 40 || event.keyCode == 83){
downDown = false;
}
}
//checking if the space bar is pressed and shooting is allowed
if (event.keyCode==32&&shootAllow) {
//making it so the user can't shoot for a bit
shootAllow=false;
//declaring a variable to be a new Bullet
var newBullet:Bullet = new Bullet();
//changing the bullet's coordinates
newBullet.x=playerShip.x+playerShip.width/2-newBullet.width/2;
newBullet.y=playerShip.y;
//then we add the bullet to stage
bulletContainer.addChild(newBullet);
}
}
function goLose() {
playerShip.removeEventListener(Event.ENTER_FRAME, moveShip);
gotoAndStop("lose");
}
stage.addEventListener(Event.ENTER_FRAME, generateParticles);
//checking if there already is another particlecontainer there
if(particleContainer == null){
//this movieclip will hold all of the particles
var particleContainer:MovieClip = new MovieClip();
addChild(particleContainer);
}
function generateParticles(event:Event):void{
//so we don't do it every frame, we'll do it randomly
if(Math.random()*10 < 2){
//creating a new shape
var mcParticle:Shape = new Shape();
//making random dimensions (only ranges from 1-5 px)
var dimensions:int = int(Math.random()*5)+1;
//add color to the shape
mcParticle.graphics.beginFill(0x999999/*The color for shape*/,1/*The alpha for the shape*/);
//turning the shape into a square
mcParticle.graphics.drawRect(dimensions,dimensions,dimensions,dimensions);
//change the coordinates of the particle
mcParticle.x = int(Math.random()*stage.stageWidth);
mcParticle.y = -10;
//adding the particle to stage
particleContainer.addChild(mcParticle);
}
//making all of the particles move down stage
for(var i:int=0;i<particleContainer.numChildren;i++){
//getting a certain particle
var theParticle:Shape = Shape(particleContainer.getChildAt(i));
//it'll go half the speed of the character
theParticle.y += mainSpeed*.5;
//checking if the particle is offstage
if(theParticle.y >= 400){
//remove it
particleContainer.removeChild(theParticle);
}
}
}
Enemy.as File Code:
package {
import flash.display.MovieClip;
import flash.events.*;
//Enemy acts as MovieClip
public class Enemy extends MovieClip {
//VARIABLES
private var _root:Object;
//speed of enemy
private var speed:int=5;
//Bullet added to stage
public function Enemy() {
addEventListener(Event.ADDED, beginClass);
addEventListener(Event.ENTER_FRAME, eFrame);
}
private function beginClass(event:Event):void {
_root=MovieClip(root);
}
private function eFrame(event:Event):void {
if (_root.gameOver) {
removeEventListener(Event.ENTER_FRAME, eFrame);
this.parent.removeChild(this);
return;
}
//moving bullet on screen, going up
y+=speed;
//move bullet if off stage
if (this.y>stage.stageHeight) {
removeEventListener(Event.ENTER_FRAME, eFrame);
_root.removeChild(this);
}
//checking if it is touching any bullets
for (var i:int = 0; i<_root.bulletContainer.numChildren; i++) {
var bulletTarget:MovieClip=_root.bulletContainer.getChildAt(i);
//now we hit test
if (this.hitTestObject(bulletTarget)) {
//remove this from the stage if bullet touches
removeEventListener(Event.ENTER_FRAME, eFrame);
_root.removeChild(this);
//remove bullet and listeners
_root.bulletContainer.removeChild(bulletTarget);
bulletTarget.removeListeners();
//increase score
_root.score+=5;
}
}
//user hit testing
if (this.hitTestObject(_root.playerShip)) {
//losing the game
_root.gameOver=true;
removeEventListener(Event.ENTER_FRAME, eFrame);
_root.goLose();
}
}
public function removeListeners():void {
this.removeEventListener(Event.ENTER_FRAME, eFrame);
}
}
}
Bullet.as File:
//This is the basic skeleton that all classes must have
package{
//we have to import certain display objects and events
import flash.display.MovieClip;
import flash.events.*;
//this just means that Bullet will act like a MovieClip
public class Bullet extends MovieClip{
//VARIABLES
//this will act as the root of the document
//so we can easily reference it within the class
private var _root:Object;
//how quickly the bullet will move
private var speed:int = 10;
//this function will run every time the Bullet is added
//to the stage
public function Bullet(){
//adding events to this class
//functions that will run only when the MC is added
addEventListener(Event.ADDED, beginClass);
//functions that will run on enter frame
addEventListener(Event.ENTER_FRAME, eFrame);
}
private function beginClass(event:Event):void{
_root = MovieClip(root);
}
private function eFrame(event:Event):void{
//moving the bullet up screen
y -= speed;
//making the bullet be removed if it goes off stage
if(this.y < -1 * this.height){
removeEventListener(Event.ENTER_FRAME, eFrame);
_root.bulletContainer.removeChild(this);
}
//checking if game is over
if(_root.gameOver){
removeEventListener(Event.ENTER_FRAME, eFrame);
this.parent.removeChild(this);
}
}
public function removeListeners():void{
removeEventListener(Event.ENTER_FRAME, eFrame);
}
}
}
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