cocos creator 公告轮播

//适用于需要轮播公告系统，本文仅是前端写法
cc.Class({
extends: cc.Component,

properties: {
    maskNode:cc.Node,
    label:cc.Label,
    _startPos:cc.Vec2,
    contentArr:[""],
},
onLoad () {
    this._startPos=cc.v2(this.maskNode.width/2,0);
    if(this.contentArr.length == 0){
        this.node.active=false;
    }
    console.log(this.label.node.position);
    this.label.node.position = this._startPos;
    this.requestCallBack();
},
requestCallBack:function(){
    this.startScroll("需要先更新标签的宽度，不然下一帧才更新");
    
},
startScroll:function(content){
    let self = this;
    if(content == null || content.length == 0)
    {
        return;
    }
    this.node.active = true;
    this.contentArr.push(content);
    if(self.label.node.getActionByTag(0) != null && this.label.node.getActionByTag(0).isDone() == false)//如果正在播放只插入数据
    {
        return;
    }

    let scrollFunc = function()
    {
        if(self.contentArr.length > 0)
        {
            self.label.string = self.contentArr.shift()
            //需要先更新标签的宽度，不然下一帧才更新，这里取到的值就会是原来的值，导致宽度计算错误
            self.label._updateRenderData(true)
            self.label.node.position = self._startPos
            let distance= self.label.node.width + self.label.node.parent.width
            let duration = distance / 100
            let seq = cc.sequence(
                cc.moveBy(duration,cc.v2(-distance,0)),
                cc.callFunc(function(){
                    self.label.string = ""
                    self.label.node.position = self._startPos
                    scrollFunc()
                })
            )
            seq.setTag(0)
            self.label.node.runAction(seq)
        }
        else
        {
            self.requestCallBack();
            // self.node.active = false
        }
    }
    scrollFunc();

},
// onDestroy()
// {
//     if(this.label.node.getActionByTag(0) != null )
//     {
//          this.label.node.stopAction(this.label.node.getActionByTag(0))
//     }
// }

});