Manually find where memory leaks are prone to occur:
1. block (using weakSelf)
2. Whether the timer is destroyed (the timer will strongly reference the controller, you can destroy the timer first in the viewWillDisappear method)
Manually find where memory leaks are prone to occur:
1. block (using weakSelf)
2. Whether the timer is destroyed (the timer will strongly reference the controller, you can destroy the timer first in the viewWillDisappear method)