Solve the problem that iOS 15 does not display IDFA permission pop-up.

After the official version of iOS 15 was released, the App encountered several problems after it was submitted for review. How to solve them?

Record the solution process here.

Debugging at iOS 15 breakpoint, it is found that attrackingmanagerauthorization status or attrackingmanagerauthorization statusnotdetermined is the callback time.

At first, I tried to call this method many times and found that I could pop up the idfa pop-up window!

Call logic

Then, after a while, I found that in most cases, putting the permission application in the `````` applicationDidBecomeActive call can pass the examination.

If other small probability fails, we can try the metaphysical delay method or carry out state cycle detection.