Cityofpomelo cocos2d 3.0版

正轉換cityofpomelo 到cocos2d 3.0 去 , apk 下遇到了問題 , invalid native object , 好像是回收問題, 怎樣解決 ?

show: function(num) {
if(!!this.mCountdownNumSprite) {
this.removeChild(this.mCountdownNumSprite);
}
if(num >= 0 && num <= 9) {
this.setVisible(true); // adb logcat 出現error : Invalid native object

  this.mCountdownNumSprite = cc.Sprite.create('#' + PREFIX_COUNTDOWN + num + '.png');
  this.mCountdownNumSprite.setAnchorPoint(0, 0);
  this.mCountdownNumSprite.setPosition(25, 23);
  this.addChild(this.mCountdownNumSprite);
}

},

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