AudioUnitSetProperty Swift errors

Question

I am trying to set the bands in my equalizer by using AudioUnitSetProperty but cant figure out the syntax in Swift. My code looks like this:

var eqFrequencies: NSArray = [ 32, 250, 500, 1000, 2000, 16000 ]
    var noBands = UInt32(eqFrequencies.count)

AudioUnitSetProperty(self.MyAppUnit, AudioUnitParameterID(kAUNBandEQProperty_NumberOfBands), AudioUnitScope(kAudioUnitScope_Global), 0, 6, UInt32(sizeof(noBands)))

Anyone know the correct way of doing this?

Answer 1

Try this (compiles for me in Xcode 6.3):

    var eqFrequencies: [UInt32] = [ 32, 250, 500, 1000, 2000, 16000 ]

    AudioUnitSetProperty(
        self.MyAppUnit,
        AudioUnitPropertyID(kAUNBandEQProperty_NumberOfBands),
        AudioUnitScope(kAudioUnitScope_Global),
        0,
        eqFrequencies,
        UInt32(eqFrequencies.count*sizeof(UInt32))
    )

Swift griped about the various int types, hence the extra casts, and the size calculation was wrong, but the band swift array of UInt32s (not NSArray) should convert automatically to UnsafePointer<Void>.