I am using the IabHelper utility classes, as recommended by Google's tutorial, and I'm being hit hard by this error. Apparently IabHelper can not run multiple async operations at the same time. I even managed to hit it by trying to start a purchase while the inventory taking was still in progress.
I have already tried to implement onActivityResult in my main class as suggested here, but I don't even get a call to that method before the error hits. Then I found this but I have no idea where to find this flagEndAsync method - it's not in the IabHelper class.
Now I'm looking for a way around this (without reimplementing the whole she-bang). The only solution I can think of is to create a boolean field asyncActive that is checked before an async task is started, and not do it if there is another task active. But that has many other problems, and doesn't work across activities. Also I'd prefer to have an async task queue up and run as soon as it's allowed to, instead of not running at all.
Any solutions for this issue?