问题
Throughout all the betas of Watchkit I was able to run my watch app seamlessly, but with the recent release this past week (8.2) my willActivate method is hardly ever called. What happens is awakeWithContext gets called and the watch stalls with the spinner spinning forever. Has this issue happened to anyone?
回答1:
I've found that locking and unlocking the device (simulator) by typing Command-L will cause the willActivate method to be called. I hope you don't have to do that on a real Apple Watch.
回答2:
Just came into the same problem yesterday.
In my case, I'm using the page navigation, and the initial view controller's awakeWithContext gets called, but willActivate is never called.
After some digging I found out that when using page navigation, ALL of the pages awakeWithContext will be called at launch time and before the initial page's willActivate. If one of the pages awakeWithContext method get stuck, the initial page's willActivate method will never be called.
You may need to check your other view controller's awakeWithContext methods to see if they are stuck.
回答3:
So, I still don't think I know exactly what is going on or what's causing it, but I'm having the exact same issue, and I have done some investigating and have some results, so I hope this helps us narrow this down. I have identified that it has something to do with the complexity of the layout that is going into my initial controller. If I change to a simpler layout for my initial controller, or if I delete "enough things" from my initial controller, then I no longer get the spinning wheel of death. (Of course that also breaks the logic of my app). My layout is a bit complex, but not that complex; there are groups nested 4 layers deep, and about 20 total UI elements (including the groups themselves), with four buttons and 4 labels. It seemed to work fine in the beta. And there's not a clear rhyme or reason to it; some combinations of layouts seem to cause it, some don't. It is deterministic; if a given layout spins on load it will always spin on load, and if it doesn't, it doesn't. When it spins, I never get willActivate. When it doesn't, I do. It does not seem to have anything to do with the contents of awakeFromContext:. I can delete everything from that method and it does not help. It also has nothing to do with assets, compiler settings, etc., etc. Other than that, I haven't figured it out yet. If anyone has any insight into this, I would love to hear it.
来源：https://stackoverflow.com/questions/29083727/watchkit-not-calling-willactivate-method