如何将 globalToLocal 与此代码结合起来？

Question

我有这套代码来创建一个简单的前后图像揭示者：

import com.greensock.*;
import com.greensock.easing.*;

function init() : void  {
    sliderbar_mc.buttonMode = true;
    sliderbar_mc.addEventListener(MouseEvent.MOUSE_DOWN,moveSliderbar);
    stage.addEventListener(MouseEvent.MOUSE_UP,stopSliderbar);
    mask_mc.alpha = 0;
    after_mc.mask = mask_mc;
    TweenLite.to(sliderbar_mc,4,{x:stage.stageWidth/2,ease:Elastic.easeOut});
    TweenLite.to(mask_mc,4,{x:stage.stageWidth/2,ease:Elastic.easeOut});
}  

function moveSliderbar(event:MouseEvent):void {
    stage.addEventListener(MouseEvent.MOUSE_MOVE,mouseMoveHandler);
}  

function stopSliderbar(event:MouseEvent):void{
    stage.removeEventListener(MouseEvent.MOUSE_MOVE,mouseMoveHandler);
}

function mouseMoveHandler(event:MouseEvent):void{
    sliderbar_mc.x = mouseX;
    if (sliderbar_mc.x > stage.stageWidth){
        sliderbar_mc.x = stage.stageWidth;
    }
    else if(sliderbar_mc.x < 0){
        sliderbar_mc.x = 0;
    }
    mask_mc.x = sliderbar_mc.x;
}

init();

但现在我需要将揭示者区域放入舞台上某个地方的自己的影片剪辑中，对于我的生活，我不知道如何使用globalToLocal 来完成这项工作...这是我的尝试：

import com.greensock.*;
import com.greensock.easing.*;

function init():void  {
    area_mc.sliderbar_mc.buttonMode = true;
    area_mc.sliderbar_mc.addEventListener(MouseEvent.MOUSE_DOWN,moveSliderbar);
    stage.addEventListener(MouseEvent.MOUSE_UP,stopSliderbar);
    area_mc.mask_mc.alpha = 0;
    area_mc.after_mc.mask = area_mc.mask_mc;
    TweenLite.to(area_mc.sliderbar_mc,3,{x:stage.stageWidth/2,ease:Elastic.easeOut});
    TweenLite.to(area_mc.mask_mc,3,{x:stage.stageWidth/2,ease:Elastic.easeOut});
}  

function moveSliderbar(event:MouseEvent):void {
    stage.addEventListener(MouseEvent.MOUSE_MOVE,mouseMoveHandler);
}  

function stopSliderbar(event:MouseEvent):void {
    stage.removeEventListener(MouseEvent.MOUSE_MOVE,mouseMoveHandler);
}

function mouseMoveHandler(event:MouseEvent):void {
    var topLeft:Point = area_mc.localToGlobal(new Point(0, 0));
    var bottomRight:Point = area_mc.localToGlobal(new Point(width, height));
    area_mc.sliderbar_mc.x = area_mc.mouseX;
    if (area_mc.mouseX > topLeft.x) {
        area_mc.sliderbar_mc.x = topLeft.x;
    }
    else if(area_mc.mouseX < bottomRight.x){
        area_mc.sliderbar_mc.x = bottomRight.x;
    }
    area_mc.mask_mc.x = area_mc.sliderbar_mc.x;
}

init();

显然它不能正常工作，我知道这一切都在 mouseMoveHandler 函数中，有人可以给我一些指示吗？

Answer 1

好吧，我玩了一下这个，我想我能够让它做你想做的事。它仍然有很多问题需要解决，并且代码很丑陋，但我尝试遵循您尝试使用的方法。为此，我在舞台上创建了所有必要的剪辑。我假设 area_mc 是您尝试在其中工作的剪辑，其他所有内容都在其中。

明天我可能会再做一点工作，但就这样了；告诉我它是否正在做你需要的事情：

var maxlenX:int = area_mc.x+area_mc.width;//calculate the maximum x area of our clip. I     do this outside the function
// Because the width will change as you move the slider. There are more elegant ways to do this, but I think this is sufficient
// for now. This will be used to stop the slider when it moves all the way to the right of our clip.
function mouseMoveHandler(event:MouseEvent):void {
    var topLeft:Point = area_mc.localToGlobal(new Point(0,0));//Translate the top   left of the clip into global coords.
    var bottomRight:Point = new Point(maxlenX,area_mc.y);//Use the maxlenX variable created above to get the bottom right point. (no need for a point here TBH).
    area_mc.sliderbar_mc.x = area_mc.mouseX;
    if (mouseX <= topLeft.x){//If the mouse is to the left of the top left point...
        area_mc.sliderbar_mc.x = area_mc.globalToLocal(new Point(topLeft.x,topLeft.y)).x;//keep the slider from moving left.
    } else if (mouseX >= bottomRight.x){//if the mouse is to the right of the bottom right point...
        area_mc.sliderbar_mc.x = area_mc.globalToLocal(new Point(bottomRight.x,bottomRight.y)).x;//keep the slider form moving right.
    }
    area_mc.mask_mc.x = area_mc.sliderbar_mc.x;//move the mask.
}