日常开发中，经常会遇到输入框被键盘遮盖的问题， 本次思路是 将键盘处理相关代码封装成一个 单利的工具类， 通过监听系统的键盘相关通知来 获取键盘信息，实现被遮盖视图的上移操作，上代码：

import Foundation
class KeyBoderHandleTool: NSObject {
    
    //可能会被遮盖的 view
    private var keyBoderHandleView :UIView?
    
    //可能会被遮盖的view 的遮盖高度
    private var keyBoderHandleHeigt :CGFloat = 0.0
    private let disposeBag = DisposeBag()
    
    //单利对象
    private static var sharedTool :KeyBoderHandleTool?
    
    //获取单利对象
    class func getSharedKeyBoderTool() ->KeyBoderHandleTool{
        
        guard let instance = sharedTool else {
            sharedTool = KeyBoderHandleTool()
            return sharedTool!
        }
        return instance
    }
    
    
    //销毁单利对象
    class func destroy() {
        sharedTool = nil
    }

    // 私有化init 初始方法
    private override init() {}
    
    
    //监听键盘弹出
    /// 处理键盘 遮盖问题
    ///
    /// - Parameters:
    ///   - handleView: 需要处理的视图
    ///   - offsetY: 如果是 可滑动的view  就传入 y 轴上的偏移量
    func handleKeyBoderAction(handleView :UIView, offsetY :CGFloat?){
        
        if keyBoderHandleView != nil {
            //更换遮盖view
            self.keyBoderHandleView = handleView
            return
        }
        
        print("开始了****************")
        self.keyBoderHandleView = handleView
        
        //监听键盘出现
        weak var weakSelf = self
        NotificationCenter.default.addObserver(forName: UIResponder.keyboardDidShowNotification, object: nil, queue: OperationQueue.main) { (notification) in
            
            let info = notification.userInfo
            
            //键盘动画时间
            let duration = (info?[UIResponder.keyboardAnimationDurationUserInfoKey] as! NSNumber).doubleValue
            
            //键盘坐标尺寸
            let keyBoderRect = (info?[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
            //获取键盘被遮盖部分的高度
            let keyBoderHeight = keyBoderRect.size.height      //获取键盘高度
            let boundHeight = UIScreen.main.bounds.size.height  //屏幕高度
            
            let viewMaxY :CGFloat = offsetY == nil ? weakSelf!.keyBoderHandleView!.frame.maxY : (weakSelf!.keyBoderHandleView!.frame.maxY-offsetY!)
            //需要处理的 view 的绝对 Y 坐标
            
            //计算出被遮盖部分的高度
            weakSelf!.keyBoderHandleHeigt = viewMaxY - (boundHeight-keyBoderHeight)
            if weakSelf!.keyBoderHandleHeigt <= 0 {
                return
            }
            
            //将其父视图 上移被遮盖的高度
            if let superView = weakSelf!.keyBoderHandleView!.superview {
                
                UIView.animate(withDuration: duration, animations: {
                    weakSelf!.keyBoderHandleView!.superview!.frame = CGRect.init(x: superView.frame.origin.x, y: superView.frame.origin.y - weakSelf!.keyBoderHandleHeigt, width: superView.bounds.size.width, height: superView.bounds.size.height)
                    
                })
                
            }
            print("打印数据--消失--\(weakSelf!.keyBoderHandleHeigt)----\(weakSelf!.keyBoderHandleView!.tag)")
            
        }
        
        NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillHideNotification, object: nil, queue: OperationQueue.main) { (notification) in
            
            let info = notification.userInfo
            if weakSelf!.keyBoderHandleHeigt <= 0{
                return
            }
            
            //键盘动画时间
            let duration = (info?[UIResponder.keyboardAnimationDurationUserInfoKey] as! NSNumber).doubleValue
            
            //将高度还原
            if let superView = weakSelf!.keyBoderHandleView!.superview {
                UIView.animate(withDuration: duration, animations: {
                    weakSelf!.keyBoderHandleView!.superview!.frame = CGRect.init(x: superView.frame.origin.x, y: superView.frame.origin.y + weakSelf!.keyBoderHandleHeigt, width: superView.bounds.size.width, height: superView.bounds.size.height)
                    
                })
            }
            
            print("打印数据--消失--\(weakSelf!.keyBoderHandleHeigt)----\(weakSelf!.keyBoderHandleView!.tag)")
            
        }
    }

    deinit {
        
        NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
        NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardDidShowNotification, object: nil)
    }
}

使用时， 只需要直接调用：

KeyBoderHandleTool.getSharedKeyBoderTool().handleKeyBoderAction(handleView: textField, offsetY: nil)

当输入框在 可滑动控件上时，记得传入 y 轴上的 offset,否则传nil

注意点：

1:在 确定不需要再监听的情况下可以 调用 工具类中的 销毁方法
2: 发生界面跳转等情况时，请先将键盘隐藏（self.view.endEditing(true)）