Have you checked the log? Did the canvas appear abnormally before and then become empty? In the operation of lock and unlock, it is necessary to judge whether it is empty
This solution in ANDROID OPEN SOURCE is fine. It can be done in time but it is of no use. The drawing frequency is too slow https://code.google.com/p/android/issues/detail?id=58385
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Have you checked the log? Did the canvas appear abnormally before and then become empty?
In the operation of lock and unlock, it is necessary to judge whether it is empty
This solution in ANDROID OPEN SOURCE is fine. It can be done in time but it is of no use. The drawing frequency is too slow
https://code.google.com/p/android/issues/detail?id=58385