KeyboardControlService.swift

//  Created by 이광용 on 2018. 7. 3..
//  Copyright © 2018년 이광용. All rights reserved.
//

import UIKit

typealias KeyboardInfo = (CGRect, TimeInterval)->()
protocol KeyboardControlDelegate: class {
    func setKyeboardControl(willShow: KeyboardInfo?, willHide: KeyboardInfo?)
    func removeKeyboardControl()
}

extension KeyboardControlService where Self: UIViewController {
    
    func setKyeboardControl(willShow: KeyboardInfo? = nil, willHide: KeyboardInfo? = nil) {
        NotificationCenter.default.addObserver(forName: .UIKeyboardWillShow, object: nil, queue: nil) { (notification) in
            self.keyboardWillShow(notification, willShow: willShow)
        }
        NotificationCenter.default.addObserver(forName: .UIKeyboardWillHide, object: nil, queue: nil) { (notification) in
            self.kyeboardWillHide(notification, willHide: willHide)
        }
    }

    func removeKeyboardControl() {
        NotificationCenter.default.removeObserver(self)
    }
    
    func keyboardWillShow(_ notification: Notification, willShow: KeyboardInfo? = nil)
    {
        guard let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else {return}
        guard let animationDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? TimeInterval else {return}
        guard let willShow = willShow else {return}
        willShow(keyboardSize, animationDuration)
    }
    
    func kyeboardWillHide(_ notification: Notification, willHide: KeyboardInfo? = nil)
    {
        guard let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else {return}
        guard let animationDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? TimeInterval else {return}
        guard let willHide = willHide else {return}
        willHide(keyboardSize, animationDuration)
    }
    
    
}
/* Example
class ViewController: UIViewController, KeyboardControlService {
    override func viewDidLoad() {
        super.viewDidLoad()
        self.setKyeboardControl(willShow: setKeyboardWillShow(), willHide: setKyeboarWillHide())
    }
    
    func setKeyboardWillShow() -> KeyboardInfo{
        return { rect, duration in
            print("keyboard will show - frame : \(rect), duration : \(duration)")
        }
    }
    
    func setKyeboarWillHide() -> KeyboardInfo{
        return { rect, duration in
            print("keyboard will hide - frame : \(rect), duration : \(duration)")
        }
    }
    deinit {
        self.removeKeyboardControl()
    }
}
*/