【纯代码】Swift-自定义PickerView单选（可修改分割线颜色、修改字体大小、修改字体颜色。）（可根据需要自己扩展）

typealias PopPickerViewCallBackClosure = (_ resultStr:NSString?) -> ()
class PopPickerView : UIView
{
    var dismissCallBack = {}
    var rowAndComponentCallBack:PopPickerViewCallBackClosure?
    
    fileprivate var blockContent : NSString?
    
    var titleLabel : UILabel?
    var divideLine : UIView?
    var confirmButton : UIButton?
    var cancelButton : UIButton?
    var overlayView : UIControl?
    var keyWindow : UIWindow?
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        self.backgroundColor = UIColor.white;
        
        if (keyWindow == nil) {
            self.keyWindow = UIApplication.shared.keyWindow
        }

        overlayView = UIControl.init(frame: UIScreen.main.bounds)
        overlayView?.backgroundColor = UIColor.init(red: 0, green: 0, blue: 0, alpha: 0.5)
        overlayView?.addTarget(self, action: #selector(hide), for: .touchUpInside)
        overlayView?.alpha = 0

        let toolView:UIView = UIView.init(frame: CGRect.init(x: 0, y: 0, width: Int(self.bounds.size.width), height: Int(40)))
        toolView.backgroundColor = .white
        addSubview(toolView)
        
        cancelButton = UIButton.init(frame: CGRect.init(x: 18, y: 0, width: 40, height: toolView.bounds.size.height))
        cancelButton?.setTitle("取消", for: .normal)
        cancelButton?.setTitleColor(newColor(225, 185, 0), for: .normal)
        cancelButton?.titleLabel?.font = UIFont.systemFont(ofSize: 14)
        cancelButton?.contentHorizontalAlignment = .left
        cancelButton?.addTarget(self, action: #selector(cancelAction), for: .touchUpInside)
        toolView.addSubview(cancelButton!)
        
        confirmButton = UIButton.init(frame: CGRect.init(x: (toolView.bounds.size.width - 30 - 18), y: 0, width: 30, height: toolView.bounds.size.height))
        confirmButton?.setTitle("确定", for: .normal)
        confirmButton?.setTitleColor(newColor(225, 185, 0), for: .normal)
        confirmButton?.titleLabel?.font = UIFont.systemFont(ofSize: 14)
        confirmButton?.contentHorizontalAlignment = .left
        confirmButton?.addTarget(self, action: #selector(confirmAction), for: .touchUpInside)
        toolView.addSubview(confirmButton!)
        
        titleLabel = UILabel.init(frame: CGRect(x: CGFloat(Int(self.bounds.size.width)/2 - 75), y: 0, width: 150, height: toolView.bounds.size.height))
        titleLabel?.text = "汽车排量"
        titleLabel?.textColor = newColor(1, 1, 1)
        titleLabel?.font = UIFont.systemFont(ofSize: 14)
        titleLabel?.textAlignment = .center
        toolView.addSubview(titleLabel!)
        
        divideLine = UIView.init(frame: CGRect(x: 0, y: (confirmButton?.superview?.frame.maxY)!, width: toolView.bounds.size.width, height: 1))
        divideLine?.backgroundColor = colorWithHexString("0xe5e5e5")
        toolView.addSubview(divideLine!)
    }
   
    convenience init(frame: CGRect,dataSource:NSArray,title:String) {
        self.init(frame: frame)
        titleLabel?.text = title
        if (dataSource.count != 0) {
            
            let picker = PickerViewBuilder.init(frame: CGRect.init(x: 38, y: ((confirmButton?.superview?.frame.maxY)! + 1), width: UIScreen.main.bounds.size.width - CGFloat(76), height: CGFloat(215)),dataSource:dataSource,contentCallBack:{ [weak self] (resultStr) in
                self?.blockContent = resultStr
            })
            picker.rowAndComponentCallBack = {[weak self](resultStr) in
                self?.blockContent = resultStr
            }
            
            self.addSubview(picker)
        }else{
            assert(dataSource.count != 0, "dataSource is not allowed to be nil")
        }
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    func show(){
        keyWindow?.addSubview(overlayView!)
        keyWindow?.addSubview(self)
        UIView.animate(withDuration: 0.25, animations: {
            self.overlayView?.alpha = 1.0
            var frame = self.frame
            frame.origin.y = UIScreen.main.bounds.size.height - self.bounds.size.height
            self.frame = frame
        }) { (isFinished) in
        }
    }

    @objc func hide() {
        self.dismissCallBack()
        UIView.animate(withDuration: 0.25, animations: {
            self.overlayView?.alpha = 0
            var frame = self.frame
            frame.origin.y = UIScreen.main.bounds.size.height
            self.frame = frame
        }) { (isFinished) in
            self.overlayView?.removeFromSuperview()
            self.removeFromSuperview()
        }
    }

    @objc func cancelAction() {
        hide()
    }
    
    @objc func confirmAction() {
        if blockContent == "" {
            showAlert(withTitle: "提示", message: "未选择任何一项！")
        }else{
            self.rowAndComponentCallBack!(blockContent)
        }
        hide()
    }
    
    @objc private func showAlert(withTitle title: String?, message: String?) {
        let alertVc = UIAlertController.init(title: title, message: message, preferredStyle: UIAlertController.Style.alert)
        alertVc.addAction(UIAlertAction.init(title: "我知道了", style: UIAlertAction.Style.cancel, handler: nil))
        UIApplication.shared.keyWindow?.rootViewController?.present(alertVc, animated: true, completion: nil)
    }
}

class PickerViewBuilder : UIPickerView, UIPickerViewDelegate,UIPickerViewDataSource {
    fileprivate var rowAndComponentCallBack:PopPickerViewCallBackClosure?//选择内容回调
    lazy var currentSelectRow : NSInteger = 0
    lazy var dataArr = NSMutableArray()

    override init(frame: CGRect) {
        super.init(frame: frame)
    }
    
    convenience init(frame:CGRect,dataSource:NSArray,contentCallBack:PopPickerViewCallBackClosure?) {
        self.init(frame: frame)
        self.backgroundColor = UIColor.white
        self.dataArr = NSMutableArray.init(array: dataSource)
        self.selectedRow(inComponent: 0)
        self.delegate = self
        self.dataSource = self
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 1
    }
    
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return dataArr.count
    }
    
    func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {
        //设置分割线
        for view in pickerView.subviews {
            if view.frame.size.height <= 1 {
                view.isHidden = false
                view.frame = CGRect(x: 0, y: view.frame.origin.y, width: UIScreen.main.bounds.size.width, height: 1)
                view.backgroundColor = colorWithHexString("0xe5e5e5")
            }
        }
        
        var pickerLabel = view as? UILabel
        if pickerLabel == nil {
            pickerLabel = UILabel()
            pickerLabel?.textAlignment = .center
            if currentSelectRow == row {
                pickerLabel?.font = UIFont.systemFont(ofSize: 16)
                pickerLabel?.textColor = newColor(225, 185, 0)
            }else{
                pickerLabel?.font = UIFont.systemFont(ofSize: 12)
                pickerLabel?.textColor = newColor(153, 153, 153)
            }
            
        }
        pickerLabel?.text = dataArr[row] as? String
        
        return pickerLabel!
    }
    
    
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return dataArr[row] as? String
    }
    
    func pickerView(_ pickerView: UIPickerView, rowHeightForComponent component: Int) -> CGFloat {
        return 33
    }
    
    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        currentSelectRow = row
        rowAndComponentCallBack!(dataArr[currentSelectRow] as? NSString)
        self.reloadAllComponents()
    }
}

let pickerView = PopPickerView.init(frame: CGRect(x: 0, y: UIScreen.main.bounds.size.height, width: UIScreen.main.bounds.size.width, height: 256), dataSource: selectParams[indexPath.row - 1] as NSArray,title:titleArr[indexPath.row])
pickerView.rowAndComponentCallBack = {(resultStr) in
    print(resultStr as Any)
        self.currentSelectCell?.rightSelectLabel.text = resultStr! as String
    }
pickerView.show()