Swift封装类似支付宝中的支付键盘(数字键盘)

当我们在项目中有支付场景的时候，系统键盘可能有时候满足不了我们的需求了，这时候就需要我们自己来封装支付键盘，并添加一些逻辑校验，以保证良好的用户体验。

这是给键盘加的一些规则：①　首位输入0后，不可继续输入整数，可输入小数点及小数点后两位②　首位不可输入小数点，若有小数点，小数点后最多可输入两位数③　最多可输入9位整数，之后可输入小数点，不可再输入整数④　光标移动删除小数点，若小数点前只有整数0，则不能删除，若是非0整数则删除小数点，保留小数点后两位数⑤　长按删除键，可连续删除
界面大概是这样的：


下面直接贴代码，封装了一个键盘工具类，可以拿来直接用：////  NumberKeyboard.swift//  JiuLiFunds////  Created by yangyunfei on 2018/1/5.//  Copyright © 2018年 JiuLiFunds. All rights reserved.//
//封装 浮点数 数字键盘
import UIKit
class NumberKeyboard: UIView {
    let baseTag = 1000        weak var firstResponder:UITextField?    var deleteTimer:Timer?    var done: (() -> Void)?  /*< 点击确定执行的回调 */        override init(frame:CGRect) {        let rect =makeRect(x: 0, y:0, width: kScreenWidth * BiLi_SCREENWIDTH_NORMAL, height:200 * BiLi_SCREENHEIGHT_NORMAL)        super.init(frame: rect)                createUI()    }    required init?(coder aDecoder:NSCoder) {        fatalError("init(coder:) has not been implemented")    }        func createUI() {                self.backgroundColor =UIColor.hexToUIColor(sourceString:"dddddd")        for i in0..<14 {            let btn = UIButton(type: .custom)            btn.backgroundColor = WHITECOLOR            //设置高亮时按钮背景颜色            btn.setBackgroundImage(UIImage.imageWithColor(color:UIColor.hexToUIColor(sourceString:"e5e5e5")), for: .highlighted)            switch i {            case 10://小数点                btn.tag = baseTag + i                btn.titleLabel?.font =FONT24                btn.setTitleColor(TITLTEXTECOLOR, for: .normal)                btn.setTitle(".", for: .normal)            case 11://键盘                btn.tag = baseTag + i                btn.setImage(UIImage.init(named:"current_keyboard_hidden"), for: .normal)            case 12://删除                btn.tag = baseTag + i                btn.setImage(UIImage.init(named:"current_keyboard_delete"), for: .normal)                let longPressGR = UILongPressGestureRecognizer(target: self, action:#selector(deleteItemLongPress))                btn.addGestureRecognizer(longPressGR)            case 13://确定                btn.tag = baseTag + i                btn.setTitle("确定", for: .normal)                btn.titleLabel?.font =FONT18                btn.setTitleColor(WHITECOLOR, for: .normal)                btn.backgroundColor = UIColor.hexToUIColor(sourceString: "0084ff")            default:                btn.tag = baseTag + i                btn.setTitle(String(i), for: .normal)                btn.titleLabel?.font =FONT24                btn.setTitleColor(TITLTEXTECOLOR, for: .normal)            }            btn.addTarget(self, action:#selector(btnClickAction), for: .touchUpInside)            self.addSubview(btn)        }    }        override func layoutSubviews() {        super.layoutSubviews()        let width:CGFloat = (self.frame.width -1.5) / 4.0        let height:CGFloat = (self.frame.height -1.5) / 4.0        let lineWidth:CGFloat =0.5                //数字1        self.viewWithTag(baseTag +1)?.frame =makeRect(x: 0, y: lineWidth, width: width, height: height)        //数字2        self.viewWithTag(baseTag +2)?.frame =makeRect(x: width + lineWidth, y: lineWidth, width: width, height: height)        self.viewWithTag(baseTag +3)?.frame =makeRect(x: 2 * width +2 * lineWidth, y: lineWidth, width: width, height: height)        self.viewWithTag(baseTag +4)?.frame =makeRect(x: 0, y: height + lineWidth*2, width: width, height: height)        self.viewWithTag(baseTag +5)?.frame =makeRect(x: width + lineWidth, y: height + 2*lineWidth, width: width, height: height)        self.viewWithTag(baseTag +6)?.frame =makeRect(x: 2 * width +2 * lineWidth, y: height + 2*lineWidth, width: width, height: height)        self.viewWithTag(baseTag +7)?.frame =makeRect(x: 0, y: (height + lineWidth)*2+lineWidth, width: width, height: height)        self.viewWithTag(baseTag +8)?.frame =makeRect(x: width + lineWidth, y: (height + lineWidth)*2+lineWidth, width: width, height: height)        self.viewWithTag(baseTag +9)?.frame =makeRect(x: (width + lineWidth)*2, y: (height + lineWidth)*2+lineWidth, width: width, height: height)                //小数点        self.viewWithTag(baseTag +10)?.frame =makeRect(x: 0, y: (height + lineWidth)*3+lineWidth, width: width, height: height)        //零        self.viewWithTag(baseTag +0)?.frame =makeRect(x: width + lineWidth, y: (height + lineWidth)*3+lineWidth, width: width, height: height)        //键盘        self.viewWithTag(baseTag +11)?.frame =makeRect(x: (width + lineWidth)*2, y: (height + lineWidth)*3+lineWidth, width: width, height: height)        //删除        self.viewWithTag(baseTag +12)?.frame =makeRect(x: (width + lineWidth)*3, y: lineWidth, width: width, height:2*height+2*lineWidth)        //确定        self.viewWithTag(baseTag +13)?.frame =makeRect(x: 3*width + lineWidth*2, y:2*height + 2*lineWidth, width: width, height:2*height+2*lineWidth)    }        @objc func btnClickAction(sender:UIButton) {                let btnTag = sender.tag        switch (btnTag) {        case baseTag +10:            self.clickedDot();        case baseTag +11:            self.clickedKeyBoard()        case baseTag +12:            self.clickedDelete()        case baseTag +13:            self.clickedSure()                    default://数字            self.clickedNumber(num: btnTag -baseTag)        }            }    //输入    func insert(text: String) {        let delegate =  self.firstResponder?.delegate        let range = selectedRange(inputView: self.firstResponder)        //回调代理方法       delegate?.textField!(self.firstResponder!, shouldChangeCharactersIn: range, replacementString: text)                self.firstResponder?.insertText(text)    }    func selectedRange(inputView: UITextField?) -> NSRange {        let beginning: UITextPosition? = inputView?.beginningOfDocument        let selectedRange: UITextRange? = inputView?.selectedTextRange        let selectionStart: UITextPosition? = selectedRange?.start        let selectionEnd: UITextPosition? = selectedRange?.end        let location: Int = inputView!.offset(from: beginning ??UITextPosition(), to: selectionStart ?? UITextPosition())        let length: Int = inputView!.offset(from: selectionStart ??UITextPosition(), to: selectionEnd ?? UITextPosition())        return NSRange(location: location, length: length)    }    //点击小数点    func clickedDot() {        let text = self.firstResponder?.text        //首位不能输入.    只能输入一个.        if text?.count !=0 && !(text?.contains("."))! {            self.insert(text:".")        }    }    //点击删除    @objc func clickedDelete() {        if (self.firstResponder?.hasText)! {            //光标Range            let selectRange = self.firstResponder?.selectedTextRange            //获取光标的位置            let beginning = self.firstResponder?.beginningOfDocument            let location = self.firstResponder?.offset(from: beginning!, to: (selectRange?.start)!)            let str = NSString.init(string: (self.firstResponder?.text)!)            if str.length <=1{                self.firstResponder?.deleteBackward()                self.insert(text:"")                return            }            if str.substring(with:NSRange.init(location:0, length: 1)) =="0" && str.substring(with:NSRange.init(location:1, length: 1)) =="."  && str.length !=2 && location == 2{                //光标移动删除小数点，若小数点前只有整数0，则不能删除                return            }else{                self.firstResponder?.deleteBackward()                self.insert(text:"")            }                    }    }    //点击键盘    func clickedKeyBoard() {        self.firstResponder?.resignFirstResponder()    }    //点击确定    func clickedSure() {        self.firstResponder?.resignFirstResponder()        if self.done !=nil {            self.done!()        }    }    //点击数字    func clickedNumber(num:Int) {        let text = self.firstResponder?.text        //首位输入0后，不可继续输入整数，可输入小数点及小数点后两位        if text?.count ==1 && text == "0" {            return        }        if (text?.contains("."))! {            //小数点后最多2位            let index = text?.index(of:".")            let subStr = text?.substring(from: index!)            let cout = subStr?.count            if cout! <= 2 {                self.insert(text:String(num))            }        }        else {//无小数点            //整数最多可以输入9位            let cout = text?.count            if cout! < 9{                self.insert(text:String(num))            }                    }            }        //长按删除    @objc func deleteItemLongPress(longPress:UILongPressGestureRecognizer) {        if longPress.state == .began {            deleteTimer = Timer.scheduledTimer(timeInterval: 0.2, target: self, selector: #selector(repeatLongPressDelete), userInfo:nil, repeats: true)        }else if (longPress.state == .ended || longPress.state == .failed || longPress.state == .cancelled){            self.cleanTimer()        }    }    @objc func repeatLongPressDelete() {
        if (self.firstResponder?.hasText)! {            self.firstResponder?.deleteBackward()            self.insert(text:"")        }    }    func cleanTimer() {        deleteTimer?.invalidate()        deleteTimer =nil    }}

在需要使用的地方，这样调用，将数字键盘作为UITextField的inputView即可：//自定义数字键盘        let keyBoardView = NumberKeyboard()        keyBoardView.firstResponder = moneyTextField        moneyTextField.inputView = keyBoardView        moneyTextField.reloadInputViews()