Where can I get example code from Apple Engineers?

For example, when Apple Engineers design something new like PHPickerViewController, I imagine that they test all the functionalities and to test all these functions, they create applications.

Where can I download the code of those applications? I mean, code that is already tested and works from Apple Engineers.

I'm sure they have tons of tested code, which would be very useful for us.

Thanks!

Answered by Minho-Park in 704516022
Accepted Answer

For example, where can I get code examples about how to get the FPS of a video? using:

AVAssetTrack and nominalFrameRate

Thanks

Where can I get example code from Apple Engineers?
 
 
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