         
         albumTitleLabel.font = .systemFontOfSize(15.0, weight: UIFontWeightThin)
         albumTitleLabel.textAlignment = .Center
-        
-        volumeSlider.minimumValue = 0.0
-        volumeSlider.maximumValue = 1.0
-        volumeSlider.value = AVAudioSession.sharedInstance().outputVolume
-        volumeSlider.addTarget(self, action: "adjustVolume:", forControlEvents: .ValueChanged)
         
         self.updateCurrentTrack()
         

        musicPickerViewController.allowsPickingMultipleItems = true
        self.presentViewController(musicPickerViewController, animated: true, completion: nil)
    }
    
    func adjustVolume(slider: UISlider) {
        let currentVolume = slider.value
        for subview in MPVolumeView().subviews {
            guard let slider = subview as? UISlider else { continue }
            slider.setValue(currentVolume, animated: true)
            slider.sendActionsForControlEvents(.TouchUpInside)
        }
    }

}


    private let nextTrackButton = UIButton(type: .Custom)
    private let prevTrackButton = UIButton(type: .Custom)
    private let musPickerButton = UIButton(type: .Custom)
    private let volumeSlider: UISlider = {
        return MPVolumeView().subviews.filter { $0 is UISlider }.map { $0 as! UISlider }.first!
    }()
    
    private var verticalConstraints: [NSLayoutConstraint] = []
    private var horizontalConstraints: [NSLayoutConstraint] = []
