Using CFArrayGetValueAtIndex in Swift with UnsafePointer (AUPreset)

Question

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>.

`let aPreset = CFArrayGetValueAtIndex(mEQPresetsArray, indexPath.row) as AUPreset` — Phu Duy, Jul 20 '16 at 07:45
The best way by far is to convert the CFArray to NSArray and go from there. — gnasher729, Jul 20 '16 at 07:46
@PhuDuy It is not posible to cast from UnsafePointer to AUPreset — Vanya, Jul 20 '16 at 07:48

score 2 · Answer 1 · answered Apr 06 '19 at 19:10

2

Here's the Swift 4 version

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

answered Apr 06 '19 at 19:10

John Stephen

score 0 · Accepted Answer · answered Jul 20 '16 at 11:17

0

Have you tried this?:

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

answered Jul 20 '16 at 11:17

OOPer

With this expression I don't get a valid AUPreset object. – Vanya Jul 20 '16 at 14:10
@Vanya, `AUPreset` is not an object type. It's C-struct and imported as Swift struct. – OOPer Jul 20 '16 at 15:33
OK, sorry SWIFT struct, but when I use "aPreset.memory" with this expression, I do get a AUPreset struct. Thank you. – Vanya Jul 21 '16 at 06:35

2 Answers2