Swift 3：修复问题类型“className”不符合协议'UIDocumentPickerDelegate'

I'm migrating my code from Swift 2 to Swift 3 but my code throws this error: Type "className" does not conform to protocol 'UIDocumentPickerDelegate'. I've migrate many parts of my document as you can see but error stills, I'm migrating my code from Swift 2 to Swift 3 b