类型强制失败：无法将 []@13a355b9 转换为 flash.display.DisplayObject

Question

我在运行时遇到此错误，没有编译错误。

package  {
import flash.display.*;
import flash.events.*;
import flash.utils.*;

public class mainCode extends MovieClip{
    //global variables go here
    public var circled:Shape = new Shape();
    public var circled2:Shape = new Shape();
    public var circled3:Shape = new Shape();
    public var angled:int = new int();
    public var circlearray1:Array = new Array(4); 
    public var circlearray2:Array = new Array(4); 
    public function mainCode(){
        makeCircle(circled, 100);
        makeCircle(circled2, 50);
        makeCircle(circled3, 50);
        for(var i:int=0; i<4; i++){circlearray1[i] = new Array(20);}
        for(var n:int=0; n<4; n++){circlearray2[n] = new Array(20);}
        stage.addEventListener(Event.ENTER_FRAME, mainLoop);

    }
    //functions go here
    private function mainLoop(e:Event){
        trace(1);
        angled+=1;
        angled%=360;
        circled.x = stage.stageWidth / 2;
        circled.y = stage.stageHeight/ 2;
        circled2.x = circled.x + 100*Math.cos(radians(angled));
        circled2.y = circled.y + 100*Math.sin(radians(angled));
        circled3.x = circled.x + 100*Math.cos(radians((angled + 180) % 360));
        circled3.y = circled.y + 100*Math.sin(radians((angled + 180) % 360));
        trace(2);
        for (var i:int = 0; i < 4; i++)
        {
            trace(3);
            if (circlearray1[i][0] != undefined) 
            {removeChild(circlearray1[i][0]);}
            if (circlearray2[i][0] != undefined) 
            {removeChild(circlearray2[i][0]);}
            trace(4);
            for (var m:int = 0; m < 19; m++)
            {
                circlearray1[i][m] = circlearray1[m+1];
                circlearray2[i][m] = circlearray2[m+1];
            }
            circlearray1[i][19] = new Shape();
            circlearray2[i][19] = new Shape();
            makeCircle(circlearray1[i][19], 25);
            makeCircle(circlearray2[i][19], 25);
            circlearray1[i][19].x = circled2.x + 50*Math.cos(radians(((-angled + (i*90)) * 2) % 360));
            circlearray1[i][19].y = circled2.y + 50*Math.sin(radians(((-angled + (i*90)) * 2) % 360));
            circlearray2[i][19].x = circled3.x + 50*Math.cos(radians(((-angled + (i*90)) * 2) % 360));
            circlearray2[i][19].y = circled3.y + 50*Math.sin(radians(((-angled + (i*90)) * 2) % 360));
            trace(8);
        }
    }
    private function makeCircle(circles:Shape, radius:int)
    {
        circles.graphics.clear();
        circles.graphics.lineStyle(2,0x000000);
        circles.graphics.beginFill(0x990000);
        circles.graphics.drawCircle(0,0,radius);
        circles.graphics.endFill();
        addChild(circles);
    }
    private function degrees(radians:Number):Number
    {
        return radians * 180/Math.PI;
    }

    private function radians(degrees:Number):Number
    {
        return degrees * Math.PI / 180;
    }
    private function killCircle(circlei:Shape):void {
        removeChild(circlei);
    }
}   
}

我已将其追溯到 {removeChild(circlearray1[i][0]);}，它似乎返回了错误。我不知道为什么要这样做，我尝试过其他选择，例如 circlearray1[i][0].parent.removeChild(circlearray1[i][0]);和 if (circlearray1[i][0] is Shape) ... ，但没有骰子。

作为参考，我试图让一些圆圈环绕其他圆圈，但最外面的圆圈在移动时留下 "image lag"（或残像）。我通过创建对象并使用 for 循环和多维数组删除它们来做到这一点，因为我不想手动输入 50 个创建对象调用并手动编辑每个调用。

Answer 1

这部分大概是：

        for (var m:int = 0; m < 19; m++)
        {
            circlearray1[i][m] = circlearray1[m+1];
            circlearray2[i][m] = circlearray2[m+1];
        }

您将最初假设为 Shapes 的端点元素分配给 Arrays 的元素。然后稍后你去 circlearray1[i][0] 假设它是 Shape 如果它不为空，但它已经是 Array 由于上面的分配。这可能是一个错字，你的意思是：

        for (var m:int = 0; m < 19; m++)
        {
            circlearray1[i][m] = circlearray1[i][m+1];
            circlearray2[i][m] = circlearray2[i][m+1];
        }

实际上有一种更简洁的方法可以做到这一点。 AS3 中的 Array 与 C# ArrayList 非常相似，您可以将元素插入任一端并从任一端提取元素，而无需手动重新索引元素：

        trace(3);
        // If you are sure the first element is not empty
        // you can get its reference removing them from 
        // the Array at the same time.
        removeChild(circlearray1[i].shift());
        removeChild(circlearray2[i].shift());
        trace(4);
        // All Array elements are automatically shifted
        // by -1 so you don't need to move each of them manually.
        circlearray1[i][19] = new Shape();
        circlearray2[i][19] = new Shape();

类型强制失败：无法将 []@13a355b9 转换为 flash.display.DisplayObject

Type Coercion failed: cannot convert []@13a355b9 to flash.display.DisplayObject

actionscript-3