自定义下拉选择框

效果图

使用方法

   let menuV =  LFPopMenuView.init(frame: CGRect.init(x: 15, y: 0, width: 80, height: 44), dataSource: ["aaa","bbb","ccc"])
        menuV.rowHeight = 30
        self.navigationController?.navigationBar.addSubview(menuV)

上代码

//
//  LFPopMenuView.swift
//  PXSSwift
//
//  Created by Pro on 2020/5/28.
//  Copyright © 2020 刘刘峰. All rights reserved.
//

import UIKit

class LFPopMenuView: UIView,UITableViewDelegate,UITableViewDataSource {
    
    var block : LFIndexCallBack?
    
    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        return self.rowHeight
    }
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return self.dataSource?.count ?? 0
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cellId = "cell"
        var cell = tableView.dequeueReusableCell(withIdentifier: cellId)
        if cell == nil {
            cell = UITableViewCell.init(style: UITableViewCell.CellStyle.default, reuseIdentifier: cellId)
        }
        cell?.textLabel?.text = self.dataSource?[indexPath.row]
        cell?.textLabel?.font = textFontSize
        return cell!
        
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        self.title = self.dataSource?[indexPath.row]
        self.dismiss()
        if self.block != nil {
            self.block!(indexPath.row)
        }
        
    }
    
    
    //MARK:-属性
    
    //标题
    var title:String? {
        didSet {
            self.titleLab.text = self.title
        }
    }
    //标题颜色
    var titleColor:UIColor?
    
    var titleFontSize:UIFont = UIFont.systemFont(ofSize: 12)
    var textFontSize:UIFont = UIFont.systemFont(ofSize: 12)

    var rowHeight:CGFloat = 44 {
        didSet {
            self.tableView.rowHeight = self.rowHeight

        }
    }
    
    var dataSource:[String]?{
        didSet {
            self.tableViewHeight = (self.dataSource?.count.cgFloat)! * self.rowHeight
        }
    }
    var tableViewHeight:CGFloat = 100
    
    var isDirectionUp:Bool?
    
    
    //MARK:-控件
    
    lazy var titleLab:UILabel = {
        let lab = UILabel()
        lab.text = "请选择"
        lab.font = self.titleFontSize
        
        
        return lab
    }()
    lazy var rightImageView:UIImageView = {
        let imageV = UIImageView()
        imageV.image = UIImage.init(named: "list_icon_drfault")
        return imageV
    }()
    
    lazy var maskBtn:UIButton = {
        let btn = UIButton()
        btn.backgroundColor = UIColor.clear
        btn.clipsToBounds = true
        btn.addTarget(self, action: #selector(show), for: UIControl.Event.touchUpInside)
        return btn
    }()
    
    
    lazy var backgroundBtn:UIButton = {
        let btn = UIButton()
        btn.backgroundColor = UIColor.clear
        btn.frame = UIScreen.main.bounds
        btn.addTarget(self, action: #selector(dismiss), for: UIControl.Event.touchUpInside)
        
        return btn
    }()
    
    
    lazy var tableView : UITableView = {
        let tab = UITableView.init(frame: .zero, style: UITableView.Style.plain)
        tab.tableFooterView = UIView()
        tab.rowHeight = rowHeight
        tab.delegate = self
        tab.dataSource = self
        tab.backgroundColor = UIColor.white
        tab.layer.shadowOffset = CGSize.init(width: 4, height: 4)
        tab.layer.shadowColor = UIColor.lightGray.cgColor
        tab.layer.shadowOpacity = 0.8
        tab.layer.shadowRadius = 4
        tab.layer.borderColor = UIColor.gray.cgColor
        tab.layer.borderWidth = 0.5
        tab.layer.cornerRadius = self.cornerRadius
        tab.separatorInset = UIEdgeInsets.init(top: 0, left: 5, bottom: 0, right: 5)
        
        
        return tab
    }()
    
    
    convenience init(frame:CGRect,dataSource:[String]) {
        self.init(frame: frame)
        self.dataSource = dataSource

        
        self.setupUI()
    }
    
    
    
    func setupUI(){
//        self.cornerRadius = 5
//        self.borderWidth = 1
//        self.borderColor = AppColor.lineColor
        

        
        self.addSubview(self.rightImageView)
        self.addSubview(self.titleLab)
        self.addSubview(self.maskBtn)
        
        self.rightImageView.snp_makeConstraints { (make) in
            make.centerY.equalTo(self);
            make.right.equalTo(self.snp_right).offset(-10);
        }
        
        self.titleLab.snp_makeConstraints { (make) in
            make.left.equalTo(self.snp_left).offset(10);
            make.right.equalTo(self.rightImageView)
            make.centerY.equalToSuperview()
            make.height.equalTo(20)
            
        }
        self.maskBtn.snp_makeConstraints { (make) in
            make.left.right.top.bottom.equalTo(self);
        }
        
        
        
    }
    
}

extension LFPopMenuView {
    @objc func show () {
        kkwindow?.addSubview(self.backgroundBtn)
        kkwindow?.addSubview(self.tableView)
        // 获取按钮在屏幕中的位置
        let frame = self.convert(self.bounds, to: kkwindow)
        let tableY = frame.origin.y + frame.size.height
        var tableViewFrame:CGRect = .zero
        tableViewFrame.size.width = frame.size.width
        tableViewFrame.size.height = self.tableViewHeight
        tableViewFrame.origin.x = frame.origin.x
        
        if tableY + self.tableViewHeight < UIScreen.main.bounds.size.height {
            tableViewFrame.origin.y = tableY
            self.isDirectionUp = false
        }else {
            tableViewFrame.origin.y = frame.origin.y - tableViewHeight
            self.isDirectionUp = true
        }
        
        self.tableView.frame = CGRect.init(x: tableViewFrame.origin.x, y: tableViewFrame.origin.y + ( self.isDirectionUp == true ? tableViewHeight:0), width: tableViewFrame.size.width, height: 0)
        
        UIView.animate(withDuration: 0.25) {
            
            self.rightImageView.transform = CGAffineTransform.init(rotationAngle: self.isDirectionUp == true ? (CGFloat(-Double.pi/2)):(CGFloat(Double.pi/2)))
                
//                CGAffineTransformRotate(weakSelf.rightImageView.transform,self.isDirectionUp?-M_PI/2:M_PI/2);

            self.tableView.frame = CGRect.init(x: tableViewFrame.origin.x, y: tableViewFrame.origin.y, width: tableViewFrame.size.width, height: tableViewFrame.size.height);
            
            
        }
        
        
    }
    
    @objc func dismiss() {
        
        UIView.animate(withDuration: 0.25, animations: {
            self.rightImageView.transform = CGAffineTransform.identity

            self.tableView.frame = CGRect.init(x: self.tableView.frame.origin.x, y: self.tableView.frame.origin.y + ( self.isDirectionUp == true ? self.tableViewHeight:0), width: self.tableView.frame.size.width, height: 0)
            

        }) { (bol) in
            self.backgroundBtn.removeFromSuperview()
            self.tableView.removeFromSuperview()
        }

    }
}