Using CFArrayGetValueAtIndex in Swift with UnsafePointer (AUPreset)

问题

My problem is simple, but tricky. I want to write this line

AUPreset *aPreset = (AUPreset*)CFArrayGetValueAtIndex(mEQPresetsArray, indexPath.row);

in Swift. The trick is that the return value is UnsafePointer<Void>.

回答1:

Have you tried this?:

    let aPreset = UnsafePointer<AUPreset>(CFArrayGetValueAtIndex(mEQPresetsArray, indexPath.row))

回答2:

Here's the Swift 4 version

let aPreset = unsafeBitCast(CFArrayGetValueAtIndex(mEQPresetsArray, indexPath), to: AUPreset.self)

来源：https://stackoverflow.com/questions/38475249/using-cfarraygetvalueatindex-in-swift-with-unsafepointer-aupreset