我如何在舞台的最左边或最右边刷出敌人并让他们移动到中间?

Question

首先我得到这个错误

ArgumentError: Error #2025: The supplied DisplayObject must be a child of the caller.
    at flash.display::DisplayObjectContainer/removeChild()
    at Game_fla::MainTimeline/testCollisions()[Game_fla.MainTimeline::frame1:205]

这是我的代码

  // ******* IMPORTS *****
import flash.events.MouseEvent;
import flash.events.Event;
import flash.events.KeyboardEvent;
import flash.events.MouseEvent;
import flash.display.MovieClip;
import flash.events.KeyboardEvent;
//*****VARIABLES****
var leftPressed:Boolean = false;
var rightPressed:Boolean = false;
var upPressed:Boolean = false;
var shootDown:Boolean = false;
var ySpeed:int = 0;
var xSpeed:int = 0;
var scrollX:int = 0;
var scrollY:int = 0;
var speedConstant:int = 5;
var friction:Number = 0.6;
var level:Number = 1;
var bullets:Array = new Array();
var container_mc:MovieClip; 
var enemies:Array;
var tempEnemy:MovieClip;

// BUTTON EVENTS EITHER CLICKED OR NOT
left_btn.addEventListener(MouseEvent.MOUSE_DOWN, moveLeft);
right_btn.addEventListener(MouseEvent.MOUSE_DOWN, moveRight);
up_btn.addEventListener(MouseEvent.MOUSE_DOWN, moveUp);
shoot_btn.addEventListener(MouseEvent.MOUSE_DOWN, shootPressed);
left_btn.addEventListener(MouseEvent.MOUSE_UP, leftUp);
right_btn.addEventListener(MouseEvent.MOUSE_UP, rightUp);
up_btn.addEventListener(MouseEvent.MOUSE_UP, upUp);
stage.addEventListener(Event.ENTER_FRAME, makeEnemies);

player.gotoAndStop('still');

stage.addEventListener(Event.ENTER_FRAME,onenter);
function onenter(e:Event):void{
    if (rightPressed == true && leftPressed == false){
        player.x += 8;
        player.scaleX = 1;
        player.gotoAndStop("walking");
        cloud.x -= 8;

    } else if (leftPressed == true && rightPressed == false){
        player.x -= 8;
        player.scaleX = -1;
        player.gotoAndStop('walking');
        cloud.x += 8;
   } else if(upPressed == true && leftPressed == false && rightPressed == false){

       }
        else{  
        rightPressed = false;
        leftPressed = false;
        player.gotoAndStop('still')}
}
// **** MOVEMENT CONTROLS *********

function shootPressed(e:MouseEvent):void{
    shootDown = true;
    if(shootDown == true){
        fireBullet();
        }
    }

function fireBullet():void
{
    var playerDirection:String;
    if(player.scaleX < 0){
        playerDirection = "left";
    } else if(player.scaleX > 0){
        playerDirection = "right";
    }
    var bullet:Bullet = new Bullet(player.x, player.y, playerDirection);
    //bullets = new Array();
    bullet.y = player.y + 8;
    stage.addChild(bullet);
    bullets.push(bullet);
    trace(bullets);
}
// BUTTON FUNCTIONS
function moveLeft(e:MouseEvent):void
{
    if(MouseEvent.MOUSE_DOWN){
    leftPressed = true;
    }else if (MouseEvent.MOUSE_UP) {
        leftPressed = false;
        }
}
function moveRight(e:MouseEvent):void
{
    if (MouseEvent.MOUSE_DOWN){
    rightPressed = true;
    }else if (MouseEvent.MOUSE_UP){
        rightPressed = false;
        }
}
function moveUp(e:MouseEvent):void
{
    if(MouseEvent.MOUSE_DOWN){
        upPressed = true;
        } else if (MouseEvent.MOUSE_UP) {
            upPressed = false;
            }
}

function leftUp(e:MouseEvent):void
{
    leftPressed = false;
}
function rightUp(e:MouseEvent):void
{
    rightPressed = false;
}
function upUp(e:MouseEvent):void
{
    upPressed = false;
}


enemies = new Array();
//Call this function for how many enemies you want to make...
function makeEnemies(e:Event):void
{
    var chance:Number = Math.floor(Math.random() * 60);
if (chance <= 2){
    //Make sure a Library item linkage is set to Enemy...
    tempEnemy = new enemy();
    tempEnemy.speed = 80;
    tempEnemy.x = Math.round(Math.random() * stage.stageWidth) * -10;
    addChild(tempEnemy);
    enemies.push(tempEnemy);
    moveEnemies();
    }
}

function moveEnemies():void
{
    var tempEnemy:MovieClip;
    for (var i:int =enemies.length-1; i>=0; i--)
    {
        tempEnemy = enemies[i];
        tempEnemy.x += tempEnemy.speed;
        tempEnemy.y = 285;
    }
}
stage.addEventListener(Event.ENTER_FRAME, testCollisions);
//Check for collisions between an enemies array and a Lasers array
function testCollisions(e:Event):void
{
    var tempEnemy:MovieClip;
    var tempLaser:MovieClip;
    for (var i:int=enemies.length-1; i >= 0; i--)
    {
        tempEnemy = enemies[i];
        for (var j:int=bullets.length-1; j>=0; j--)
        {
            tempLaser = bullets[j];
            if (tempLaser.hitTestObject(tempEnemy))
            {
                removeChild(tempEnemy);
                removeChild(tempLaser);
                trace("BULLET HIT");
                stage.addEventListener(Event.ENTER_FRAME, testCollisions);

            } 
        }
    }
}

我明白，我需要引用父每当我removeChild在testCollision函数，但我不知道在哪里。

我还想让僵尸从舞台上刷出来，以平稳的速度向中心移动，我有代码，他们似乎只是在舞台的左边刷出来。所以我需要将它们从舞台上衍生出来让它们移动到中间并改变ScaleX的位置来改变它们的方向但我不知道该怎么做请帮忙

Answer 1

我认为你可以通过将removeChild(tempLaser)更改为stage.removeChild(tempLaser)来修复你列出的错误，因为阶段是你添加子弹的地方，所以这就是你需要删除它们的地方。

我会给你一个关于僵尸运动的提示，但你可能会想找一个编程论坛/朋友/教授来帮助解决像这样的一般代码设计问题。在moveEnemies中，你需要决定僵尸是否应该向左/向右移动(基于它们的x位置比玩家的大还是小)，以及它们是否应该向上/向下移动(基于它们的y位置比玩家的大还是小)。

例如，如果他们的x位置比玩家的大，你将执行tempEnemy.x -= tempEnemy.speed，如果小，你将执行tempEnemy.x += tempEnemy.speed。但正如我所说，这个网站并不是为这些类型的设计问题而设计的。