如何删除创建的子代，然后重新启动动画

Question

我编写了以下代码来创建和拖动字母，如果它很脏，很抱歉，但是我正在学习AS3，我需要您帮助我完成代码以删除创建的字母并重新启动动画，并带有一个按钮。

LetraA.addEventListener(MouseEvent.MOUSE_DOWN, arrastrarA);
function arrastrarA(event: MouseEvent): void {
    var LetraA_1 = new letraA;
    addChild(LetraA_1);
    LetraA_1.x = 72.15;
    LetraA_1.y = 316.45;
    LetraA_1.startDrag();
}

LetraB.addEventListener(MouseEvent.MOUSE_DOWN, arrastrarB);
function arrastrarB(event: MouseEvent): void {
    var LetraB_1 = new letraB;
    addChild(LetraB_1);
    LetraB_1.x = 170.35;
    LetraB_1.y = 316.45;
    LetraB_1.startDrag();

stage.addEventListener(MouseEvent.MOUSE_UP, soltarletras);
function soltarletras(event: MouseEvent): void {
    LetraA.stopDrag();
}

Resetear.addEventListener(MouseEvent.CLICK, eliminarhijos);

function eliminarhijos(event:MouseEvent):void
{
    "I need help here please"
}

Answer 1

有几种方法。这取决于您拥有什么，可以做什么，不能做什么。

方式№1。您可以为所有字母设置一个单独的容器，然后完全清理该容器。

// Before your code.
var TheABC:Sprite = new Sprite;
addChild(TheABC);

// Inside the letter creation methods.
// I do hope you do not have 26 separate functions for that.

    // ...
    TheABC.addChild(LetraA_1);
    // ...

    // ...
    TheABC.addChild(LetraB_1);
    // ...

// So, the finale is very simple.
function eliminarhijos(e:MouseEvent):void
{
    // Remove all the children at once.
    TheABC.removeChildren();

    // If, by any chance, you have a VERY old Flash
    // below Player 11, the one above won't work so
    // you would have to resolve to the one below.

    // Proceed while there are children at all.
    // while (ThABC.numChildren)
    // {
    //     // Remove the firstmost child.
    //     TheABC.removeChildAt(0);
    // }
}

方式№2。入学名单。您保留了需要删除的内容的列表。

// Before your code.
var ABClist:Array = new Array;

// Inside the letter creation methods.

    // ...
    addChild(LetraA_1);
    ABClist.push(LetraA_1);
    // ...

    // ...
    addChild(LetraB_1);
    ABClist.push(LetraB_1);
    // ...

// Finally.
function eliminarhijos(e:MouseEvent):void
{
    // Iterate over the listed letters.
    for each (var aLetter:DisplayObject in ABClist)
    {
        // Removes each of the listed letters, one by one.
        removeChild(aLetter);
    }

    // Clear the list.
    ABClist.length = 0;
}

方式№3。标记。如果上述任何原因都不适合您，则可以使用特定方式命名这些字母，以便从其他对象中过滤出来。

// Inside the letter creation methods.

    // ...
    addChild(LetraA_1);
    LetraA_1.name = "LETTER";
    // ...

    // ...
    addChild(LetraB_1);
    LetraB_1.name = "LETTER";
    // ...

// Finally.
function eliminarhijos(e:MouseEvent):void
{
    // Iterate over all children. Backward loop, because if you
    // remove something, the whole body of children shifts down.
    for (var i:int = numChildren - 1; i >= 0; i--)
    {
        var aChild:DisplayObject = getChildAt(i);

        // So you have a criteria to figure out if it is a letter or not.
        if (aChild.name == "LETTER")
        {
            removeChild(aChild);
        }
    }
}

方式№4。变成怪异的。如果以上方法都不适合您，那么仍然可以将字母与其他对象分开。

// You need to list all the classes of your letters here.
var LetterBox:Array = [letraA, letraB];

// The clean up.
function eliminarhijos(e:MouseEvent):void
{
    // Iterate over all children. Backward loop, because if you
    // remove something, the whole body of children shifts down.
    for (var i:int = numChildren - 1; i >= 0; i--)
    {
        var aChild:DisplayObject = getChildAt(i);

        // Now iterate over all possible letter classes
        // to figure out if the given child belongs to any of them.
        for each (var aClass:Class in LetterBox)
        {
            // Match criteria.
            if (aChild is aClass)
            {
                removeChild(aChild);
                break;
            }
        }
    }
}