flash 怎樣制作可以用鼠標拖動旋轉的轉盤

妳需要壹個隱形的參照點，用它來計算圓形的下壹步的角度增量，然後再把新的角度賦予圓形。

var?sp:Shape?=?new?Shape();

sp.x?=?circle_mc.x;

sp.y?=?circle_mc.y;

var?spRot:Number;

var?circle_mcRot:Number;

circle_mc.addEventListener(MouseEvent.MOUSE_DOWN,onSelected);

function?onSelected(e:MouseEvent)

{

circle_mcRot?=?circle_mc.rotation;

onMove(null);

spRot?=?sp.rotation;

circle_mc.addEventListener(MouseEvent.MOUSE_MOVE,onMove);

stage.addEventListener(MouseEvent.MOUSE_UP,onStop);

}

function?onMove(e:MouseEvent)

{

var?a:Number?=?mouseX?-?sp.x;

var?b:Number?=?mouseY?-?sp.y;

if(a?>?0)

{

sp.rotation?=?Math.atan(b/a)?*?180?/?Math.PI;

}

else?if(a?<?0)

{

sp.rotation?=?Math.atan(b/a)?*?180?/?Math.PI?+?180;

}

if(e)

{

circle_mc.rotation?=?circle_mcRot?+?sp.rotation?-?spRot;

e.updateAfterEvent();

}

}

function?onStop(e:MouseEvent)

{

circle_mc.removeEventListener(MouseEvent.MOUSE_MOVE,onMove);

stage.addEventListener(MouseEvent.MOUSE_UP,onStop);

}