iosDetectVolume

import AVFoundation

class EACAudioManager: NSObject {
	static let sharedInstance = EACAudioManager()
	var volumeDidChange = { (newVolume: Float) -> () in }
	var currentVolume: Float { return AVAudioSession.sharedInstance().outputVolume }
	override init() {
		super.init()
		try! AVAudioSession.sharedInstance().setActive(true)
		AVAudioSession.sharedInstance().addObserver(self, forKeyPath: "outputVolume", options: NSKeyValueObservingOptions.New, context: nil)
	}
	
	override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer<Void>) {
		if let keyPath = keyPath {
			switch keyPath {
			case "outputVolume":
				volumeDidChange(object!.valueForKeyPath(keyPath) as! Float)
			default:()
			}
		}
	}
}