从类中访问时间线变量？

Posted 2023-02-18

【中文标题】从类中访问时间线变量？

【英文标题】：Accessing timeline variables from a class?

【发布时间】：2015-02-22 06:29:27

【问题描述】：

在我的程序的一个框架中，我有一个“玩家”的代码，它本质上是一门跟随角色的大炮，细节并不重要。所以我想把这门大炮做成一个类，然后我可以把它作为一个电影剪辑放在舞台上，并让类似的大炮提供类似的功能。所以基本上我需要把它变成一个以某种方式与时间线变量交互的类？

现在 Player 类看起来像这样

package 

    import flash.display.*;
    import flash.events.*;
    import flash.ui.*;

    public class Player extends MovieClip
    
    public function Player() 

警告代码转储你不必阅读所有这些，这是我需要制作成一个类的播放器代码，以便我可以让更多的玩家使用不同的参数而不是全部跟随角色等......那么我该怎么做呢？这段代码目前正在与舞台上的对象和时间轴中的其他变量进行交互。

// player settings
var _rotateSpeedMax:Number = 20;
var _gravity:Number = .10;
// projectile gun settings
var _bulletSpeed:Number = 4;
var _maxDistance:Number = 200;
var _reloadSpeed:Number = 250;//milliseconds
var _barrelLength:Number = 20;
var _bulletSpread:Number = 5;
// gun stuff
var _isLoaded:Boolean = true;
var _isFiring:Boolean = false;
var _endX:Number;
var _endY:Number;
var _startX:Number;
var _startY:Number;
var _reloadTimer:Timer;
var _bullets:Array = [];

// array that holds walls

var _solidObjects:Array = [];
// global vars
var _player:MovieClip;
var _dx:Number;
var _dy:Number;
var _pcos:Number;
var _psin:Number;
var _trueRotation:Number;
/**
 * Constructor
 */
_solidObjects = [world.wall01,world.wall02,world.wall03,world.wall04];
stage.addEventListener(Event.ENTER_FRAME, enterFrameHandler);
stage.addEventListener(MouseEvent.MOUSE_DOWN, onMouseDownHandler);
stage.addEventListener(MouseEvent.MOUSE_UP, onMouseUpHandler);
//character.addEventListener(Event.ENTER_FRAME, moveDude);


//////////////////////////////////////;
// Player & Weapon Methods
//////////////////////////////////////

/**
 * Creates player
 * Uses "Player" movieclip linked in library
 */
createPlayer();
function createPlayer():void


    // attach player movieclip from library

    // position player in center
    if (character!=null&&_player!=null)
    

        _player.x = character.x +5;
        _player.y = character.y +5;
    
    else if (_player ==null)
    
        _player = new Player();

        // add to display list
        stage.addChild(_player);
    


/**
 * Fire weapon
 */
function fire():void

    // check if firing
    if (! _isFiring)
    
        return;
    

    // check if reloaded
    if (! _isLoaded)
    
        return;
    

    // create bullet
    createBullet();

    // start reload timer
    _reloadTimer = new Timer(_reloadSpeed);
    _reloadTimer.addEventListener(TimerEvent.TIMER, reloadTimerHandler);
    _reloadTimer.start();

    // set reload flag to false;
    _isLoaded = false;


/**
 * Creates a bullet movieclip and sets it's properties
 */
function createBullet():void

    // precalculate the cos & sine
    _pcos = Math.cos(_player.rotation * Math.PI / 180);
    _psin = Math.sin(_player.rotation * Math.PI / 180);

    // start X & Y
    // calculate the tip of the barrel
    _startX = _player.x - _barrelLength * _pcos;
    _startY = _player.y - _barrelLength * _psin;

    // end X & Y
    // calculate where the bullet needs to go
    // aim 50 pixels in front of the gun
    _endX = _player.x - 50 * _pcos + Math.random() * _bulletSpread - _bulletSpread * .5;
    _endY = _player.y - 50 * _psin + Math.random() * _bulletSpread - _bulletSpread * .5;

    // attach bullet from library
    var tempBullet:MovieClip = new Bullet();

    // calculate velocity
    tempBullet.vx = (_endX - _startX) / _bulletSpeed;
    tempBullet.vy = (_endY - _startY) / _bulletSpeed;

    // set position
    tempBullet.x = _startX;
    tempBullet.y = _startY;

    // save starting location
    tempBullet.startX = _startX;
    tempBullet.startY = _startY;

    // set maximum allowed travel distance
    tempBullet.maxDistance = stage.stageHeight;//_maxDistance;

    // add bullet to bullets array
    _bullets.push(tempBullet);

    // add to display list;
    stage.addChild(tempBullet);


/**
 * Updates bullets
 */
function updateBullets():void

    var i:int;
    var tempBullet:MovieClip;

    // loop thru _bullets array
    for (i = 0; i < _bullets.length; i++)
    
        // save a reference to current bullet
        tempBullet = _bullets[i];

        // check if gravity is enabled
        if (gravityCheckbox.selected)
        
            // add gravity to Y velocity
            tempBullet.vy +=  _gravity;

        

        // update bullet position
        tempBullet.x +=  tempBullet.vx;
        tempBullet.y +=  tempBullet.vy;

        // check if bullet went too far
        if (getDistance(tempBullet.startX - tempBullet.x, tempBullet.startY - tempBullet.y) > tempBullet.maxDistance + _barrelLength)
        
            destroyBullet(tempBullet);
        

        // check for collision with walls
        if (checkCollisions(tempBullet.x,tempBullet.y))
        
            destroyBullet(tempBullet);
        
    


/**
 * Destroys bullet
 * @parambulletTakes bullet movieclip
 */
function destroyBullet(bullet:MovieClip):void

    var i:int;
    var tempBullet:MovieClip;

    // loop thru _bullets array
    for (i = 0; i < _bullets.length; i++)
    
        // save a reference to current bullet
        tempBullet = _bullets[i];

        // if found bullet in array
        if (tempBullet == bullet)
        
            // remove from array
            _bullets.splice(i, 1);

            // remove from display list;
            bullet.parent.removeChild(bullet);

            // stop loop;
            return;
        
    


/**
 * Reload weapon
 */
function reloadWeapon():void

    _isLoaded = true;


/**
 * Checks for collisions between points and objects in _solidObjects
 * @returnCollision boolean
 */
function checkCollisions(testX:Number, testY:Number):Boolean

    var i:int;
    var tempWall:MovieClip;

    // loop thru _solidObjects array
    for (i = 0; i < _solidObjects.length; i++)
    
        // save a reference to current object
        tempWall = _solidObjects[i];

        // do a hit test
        if (tempWall.hitTestPoint(testX,testY,true))
        
            return true;

            // stop loop
            break;
        
    
    return false;


/**
 * Calculate player rotation 
 */
function updateRotation():void

    // calculate rotation based on mouse X & Y
    _dx = _player.x - stage.mouseX;
    _dy = _player.y - stage.mouseY;

    // which way to rotate
    var rotateTo:Number = getDegrees(getRadians(_dx,_dy));

    // keep rotation positive, between 0 and 360 degrees
    if (rotateTo > _player.rotation + 180)
    
        rotateTo -=  360;
    
    if (rotateTo < _player.rotation - 180)
    
        rotateTo +=  360;
    

    // ease rotation
    _trueRotation = (rotateTo - _player.rotation) / _rotateSpeedMax;

    // update rotation
    _player.rotation +=  _trueRotation;


//////////////////////////////////////
// Event Handlers
//////////////////////////////////////

/**
 * Enter Frame handler
 * @parameventUses Event
 */
function enterFrameHandler(event:Event):void

    createPlayer();
    updateRotation();
    updateBullets();
    fire();


/**
 * Mouse Up handler
 * @parameUses MouseEvent
 */
function onMouseUpHandler(event:MouseEvent):void

    _isFiring = false;


/**
 * Mouse Down handler
 * @parameUses MouseEvent
 */
function onMouseDownHandler(event:MouseEvent):void

    _isFiring = true;


/**
 * Reload timer
 * @parameTakes TimerEvent
 */
function reloadTimerHandler(e:TimerEvent):void

    // stop timer
    e.target.stop();

    // clear timer var;
    _reloadTimer = null;

    reloadWeapon();


//////////////////////////////////////
// Utilities
//////////////////////////////////////

/**
 * Get distance
 * @paramdelta_x
 * @paramdelta_y
 * @return
 */
function getDistance(delta_x:Number, delta_y:Number):Number

    return Math.sqrt((delta_x*delta_x)+(delta_y*delta_y));


/**
 * Get radians
 * @paramdelta_x
 * @paramdelta_y
 * @return
 */
function getRadians(delta_x:Number, delta_y:Number):Number

    var r:Number = Math.atan2(delta_y,delta_x);

    if (delta_y < 0)
    
        r +=  (2 * Math.PI);
    
    return r;


/**
 * Get degrees
 * @paramradiansTakes radians
 * @returnReturns degrees
 */
function getDegrees(radians:Number):Number

    return Math.floor(radians/(Math.PI/180));

【问题讨论】：

我建议你不要在时间轴上编码。但是从类中你可以访问像这样的变量 MovieClip(root).variable

【参考方案1】：

您可以从类中访问如下变量：MovieClip(root).variable

【讨论】：

那么，如何访问舞台上的对象？我有对象 world.wall01、world.wall02 等。（对象内的 wall0number 实例名称和世界实例名称）当我尝试将它们添加到上面提到的列表中时，我收到了这个奇怪的错误 TypeError: Error #1123: Filter operator not supported on type class flash.display.MovieClip. at Player() at Maintest_fla::MainTimeline/createPlayer() 这是我是如何通过他们的_solidObjects = [MovieClip.(root).world.wall01,MovieClip.(root).world.wall02,MovieClip.(root).world.wall03,MovieClip.(root).world.wall04];

@Altrows - 去掉MovieClip 之后的句点，这就是引发过滤操作错误的原因。仔细看@tziuka 的回答，MovieClip 后面没有句号。

天哪，我是个白痴，有时我想我需要更多的睡眠）：谢谢。