Cocos2dx -JS Add JSBindings for a button to open a url

Hi I have a small project written in Javascript using cocos2dx js. I require someone to show me how to add JS bindings/ call to C++ function using JNI to create a menu button that will open the url for the appstore in ios and google play in java. the code is there on the forum but the tutorial is unfortunately in Chinese language. If you expertise in cocos2dx js this should be pretty straight forward.