I have not looked at your code, but the first thing I would make sure you are doing is to add the "ChromeClient" to the webview using WebViewExtras (do a search in this forum)
This it true for everything EXCEPT booking an event.
The only way to book an event is to use the checkout experience as linked in the first post.
Once an event is booked then the API works great to get the order etc.
I already am using the REST API to read the list of events / display them etc, even authenticate the user to display their list of booked events.
My name is Jason and I am a member Eventbrite's Customer Experience Team. We currently don't have API endpoints that will allow users to check out on your website. However, we do have an embedded checkout that you could use for your website. Here is the documentation on our embedded checkout widget.
Ohh i see. Honestly i did not read their pages in complete... I just found the site i posted, read there that they are using REST and my 1st thought was to suggest okhttputils2
If I put the same code webpage code that I have in the string for LoadHtml into a php script and then call the php script with a parameter which is the event id then it all works!
It seems to be something to do with SSL, but not quite sure.