LFSlider.swift

//
//  LFSlider.swift
//  LFSlider
//
//  Created by Lucas Farah on 3/12/16.
//  Copyright © 2016 Lucas Farah. All rights reserved.
//

import UIKit

class LFSlider: UIView {
  
  var height: CGFloat?
  var width: CGFloat?
  
  var label: UILabel?
  var slider: UISlider?
  var color: UIColor?
    {
    didSet
    {
      self.label?.textColor = self.color
      self.slider?.thumbTintColor = self.color
    }
  }
  
  override init(frame:CGRect)
  {
    super.init(frame: CGRect(x: 100, y: 100, width: frame.width, height: frame.height))
    
    self.height = frame.height
    self.width = frame.width
    
    self.slider = UISlider(frame: CGRect(x: 0, y: 0, width: self.frame.width * 0.6, height: self.frame.height))
    self.slider!.maximumValue = 100
    self.slider!.value = 50
    self.slider!.addTarget(self, action: #selector(LFSlider.sliderValueChanged(_:)), forControlEvents: .ValueChanged)
    self.addSubview(self.slider!)
    
    self.label = UILabel(frame: CGRect(x: self.slider!.frame.width + (self.frame.width * 0.1), y: 0, width: self.frame.width - self.slider!.frame.width - (self.frame.width * 0.1), height: self.frame.height))
    self.label!.text = "\(Int(self.slider!.value))%"
    self.label!.adjustsFontSizeToFitWidth = true
    
    self.addSubview(self.label!)
  }
  
  required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
  }
  
  func sliderValueChanged(sender: UISlider)
  {
    self.label?.text = "\(Int(sender.value))%"
  }
  
  func setValue(value: Float, duration: Double = 4) {
    self.slider?.setValue(value, duration: duration)
    self.label?.setValue(Int(value), duration: duration)
  }
}

extension NSTimer
{
  public static func runThisEvery(seconds seconds: NSTimeInterval, handler: NSTimer! -> Void) -> NSTimer {
    let fireDate = CFAbsoluteTimeGetCurrent()
    let timer = CFRunLoopTimerCreateWithHandler(kCFAllocatorDefault, fireDate, seconds, 0, 0, handler)
    CFRunLoopAddTimer(CFRunLoopGetCurrent(), timer, kCFRunLoopCommonModes)
    return timer
  }
}

extension UILabel
{
  func setValue(number: Int, duration: Double)
  {
    if var currentNumber = Int(self.text!.substringWithRange(Range<String.Index>(self.text!.startIndex ..< self.text!.endIndex.advancedBy(-1))))
    {
      let timerNumber = currentNumber
      NSTimer.runThisEvery(seconds: duration / Double(abs(number - timerNumber))) { (timer) -> Void in
        
        if currentNumber == number
        {
          timer.invalidate()
        }
        else if currentNumber < number
        {
          currentNumber += 1
          self.text = "\(currentNumber)%"
        }
        else if currentNumber > number
        {
          currentNumber -= 1
          self.text = "\(currentNumber)%"
        }
      }
    }
  }
}
extension UISlider
{
  /// EZSE: Slider moving to value with animation duration
  public func setValue(value: Float, duration: Double) {
    UIView.animateWithDuration(duration, animations: { () -> Void in
      self.setValue(self.value, animated: true)
    }) { (bol) -> Void in
      UIView.animateWithDuration(duration, animations: { () -> Void in
        self.setValue(value, animated: true)
        }, completion: nil)
    }
  }
}