Scan QR Code program flash back

Today the client came to see our project. To the customer's mobile phone installed the app (IOS version), scanning the QR code when the program has been flashing, the boss is a bit unhappy, let me find the reason. All right, find it. A breakpoint query is really a crash in this type

The crash log is as follows:

A little unprepared, testing so many of the machine is no problem, it is not this? Troubleshooting code problems, go to the general settings in a look, the camera access rights did not open, really that what, so the rights to open no longer crash, remember a lesson here--also put a code, let the camera permissions do not open when the user to remind users to set the relevant settings. The code is as follows:

Scan QR Code program flash back