参考代码：

this.btnOff.addEventListener("click", off.bind(this));
this.btnBomb.addEventListener("click", bomb.bind(this));
var _this = this;
var pb = null;
function off() {
	if (pb == null) {
		pb = new lib.sb1link();
		pb.x = 600;
		pb.y = 300;
		pb.planeBombObj.bombObj.visible = false;
		_this.addChild(pb);
		pb.gotoAndPlay(1);
		pb.planeBombObj.bombObj.addEventListener("bombover", over.bind(this));
		pb.addEventListener("planeover", over.bind(this));
	}
}
function over() {
	console.log("ccss")
	if (pb != null) {
		pb.gotoAndPlay(0);
		pb.planeBombObj.bombObj.removeEventListener("bombover",over.bind(this));
		pb.removeEventListener("planeover",over.bind(this));
		_this.removeChild(pb);
		pb = null;
	}
}
function bomb() {
	pb.planeBombObj.bombObj.visible = true;
	pb.planeBombObj.bombObj.gotoAndPlay(1);
}