AVAudioEngine seek the time of the song

Question

I am playing a song using AVAudioPlayerNode and I am trying to control its time using a UISlider but I can\'t figure it out how to seek the time using

Answer 1

After MUCH trial and error I think I have finally figured this out.

First you need to calculate the sample rate of your file. To do this get the last render time of your AudioNode:

var nodetime: AVAudioTime  = self.playerNode.lastRenderTime
var playerTime: AVAudioTime = self.playerNode.playerTimeForNodeTime(nodetime)
var sampleRate = playerTime.sampleRate

Then, multiply your sample rate by the new time in seconds. This will give you the exact frame of the song at which you want to start the player:

var newsampletime = AVAudioFramePosition(sampleRate * Double(Slider.value))

Next, you are going to want to calculate the amount of frames there are left in the audio file:

var length = Float(songDuration!) - Slider.value
var framestoplay = AVAudioFrameCount(Float(playerTime.sampleRate) * length)

Finally, stop your node, schedule the new segment of audio, and start your node again!

playerNode.stop()

if framestoplay > 1000 {
   playerNode.scheduleSegment(audioFile, startingFrame: newsampletime, frameCount: framestoplay, atTime: nil,completionHandler: nil)
}

playerNode.play()

If you need further explanation I wrote a short tutorial here: http://swiftexplained.com/?p=9