Open Radar

 
Area:
AVFoundation

Summary:

In Xcode 9 I can set the audio session category with this function

```
try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
```

but on Xcode 10/iOS12/swift 4.2 that method has disappeared from Swift. It's still available on Objc but not anymore on Swift.

It's not possible to configure the audio session category on iOS 9.

Steps to Reproduce:

Type these instructions on a project that support iOS9 and newer

 do {
            if #available(iOS 11.0, *) {
                try audioSession.setCategory(.playback, mode: .default, policy: .longForm, options: [])
            } else if #available(iOS 10.0, *) {
                try audioSession.setCategory(.playback, mode: .default, options: [])
            } else {
                // Compiler error: 'setCategory' is unavailable in Swift
                try audioSession.setCategory(AVAudioSession.Category.playback)
            }
        } catch let error {
            print("Unable to configure audio sesson category: \(error)")
        }

The code will not compile.

Expected Results:

That instruction should be STILL accessible and usable in swift and the app should compile.

Actual Results:

Compiler report the following error

'setCategory' is unavailable in Swift

Version/Build:

Version 10.0 beta 4 (10L213o)
iOS 12, Swift 4.2

Configuration:

Nothing special