Running a Javascript function from the JS within a Cocoa Web View is relatively easy, but having a Javascript function run an Objective-C method isn't as easy. Since Apple's documentation leaves a lot to be desired and there wasn't a lot of help in the usual places, I created the simplest proof of concept to show the two-way connections between JS and ObjC functions and methods.
Also, since this is an excellent way to do javascript coding inside an objective-C application, I included the ability to use a local HTML file, a remote HTML file and a remote HTML file that includes a POST so you can send a user and token, say.
No license, no warranty, use as is for any purpose you see fit.