Actionscript 3.0 MovieClip冲突

Question

我正在开发一个包含例如8件的馅饼的项目。馅饼是一个MovieClip，每一块都是一个MovieClip。这是一个8件套的圆圈。

pie_mc.piece1_mc.addEventListener(MouseEvent.CLICK, fadeout);
pie_mc.piece2_mc.addEventListener(MouseEvent.CLICK, fadeout);
pie_mc.piece3_mc.addEventListener(MouseEvent.CLICK, fadeout);
pie_mc.piece4_mc.addEventListener(MouseEvent.CLICK, fadeout);
pie_mc.piece5_mc.addEventListener(MouseEvent.CLICK, fadeout);
pie_mc.piece6_mc.addEventListener(MouseEvent.CLICK, fadeout);
pie_mc.piece7_mc.addEventListener(MouseEvent.CLICK, fadeout);
pie_mc.piece8_mc.addEventListener(MouseEvent.CLICK, fadeout);   

当我点击piece1_mc时，位图图片的某些区域会重叠piece1_mc，然后此片段会变淡而不是piece1_mc。