cocos2dx js版本 在骨骼上绑定动画会移动

Cocos2d-x
#1

如题，上图为证

随着随着时间增加，一直往下飘， 下面是代码
var arm = this.createFightArm(“TTD_Boomerang”, true)
var paoArm = this.createFightArm(“TTD_Boomerang”, true)
paoArm.getAnimation().play(“pao”)

        //this.addToParentCenter(this._baseLayer, arm)
        var size = this._baseLayer.getContentSize()
        this.addToParent(this._baseLayer, arm, cc.p(size.width/2, size.height-100))
        //paoArm.setAnchorPoint(0.5,0.5)
        var bone = arm.getBone("pao")
        if (bone) {
            bone.addDisplay(paoArm, 0)
            bone.changeDisplayWithIndex(0, true)
        }