UITableview 设置组圆角，以及最后或首行去线处理

效果

效果图.png

调用方法

        cell.setLocationState(items: items,
                              indexPathRow: indexPath.row)

操作

让cell 遵循协议，并重写协议方法

extension MQUnscrambleCell: ViewLocationStateProtocl {
    // 重写设置位置状态方法
    public func setLocationState(_ locationState: ViewLocationState) {
        // 最后一行去线
        lineV.isHidden = locationState.isLast
        // 设置组圆角
        bgView.setCorner(locationState, cornerRadius: 50)
    }
}

新建文件CellLocationState.swift，并写入复制以下代码到文件中

//
//  CellLocationState.swift
//  MQBaseComponents
//
//  Created by 消摇 on 2019/7/20.
//  Copyright © 2019 消摇. All rights reserved.
//

import Foundation
import  UIKit

/// 视图位置状态
public enum ViewLocationState {
    case non // 未定义
    case onlyOne // 只有一个
    case begin // 开头
    case center // 中间
    case end // 结尾
    
    public init() {
        self = .non
    }
}

extension ViewLocationState {
    public var isFirst: Bool {
        return self == .onlyOne || self == .begin
    }
    
    public var isLast: Bool {
        return self == .onlyOne || self == .end
    }
}

extension ViewLocationState {
    // 通过item及indexPathRow获取cell的位置状态
    static func state<T>(items: [T],
                         indexPathRow: Int) -> ViewLocationState {
        guard items.count > 0 else { return .non }
        if items.count == 1 {
            return .onlyOne
        }
        
        if indexPathRow == 0 {
            return .begin
        }
        
        if indexPathRow == items.count - 1 {
            return .end
        }
        return .center
    }
}

/// 位置状态协议
public protocol ViewLocationStateProtocl {
    func setLocationState(_ locationState: ViewLocationState)
}

extension ViewLocationStateProtocl {
    /// 调用该方法设置view的位置状态
    public func setLocationState<T>(items: [T],
                                    indexPathRow: Int) {
        let locationState = ViewLocationState
            .state(items: items,
                   indexPathRow: indexPathRow)
        setLocationState(locationState)
    }
    
    /// 设置默认实现
    public func setLocationState(_ locationState: ViewLocationState) {
        print("重写此方法 setLocationState == \(locationState)")
    }
}

/// 给view扩展设置部分角是原角的方法
extension UIView {
    
    /// 设置圆角
    ///
    /// - Parameters:
    ///   - locationState: 位置状态
    ///   - cornerRadius: 圆角半径
    public func setCorner(_ locationState: ViewLocationState,
                          cornerRadius: CGFloat = 5) {
        // 相对布局需要刷新UI
        layoutIfNeeded()
        setNeedsLayout()
        var maskedCorners: CACornerMask
        var rectCorner: UIRectCorner
        switch locationState {
        case .onlyOne:
            maskedCorners = CACornerMask(
                arrayLiteral: CACornerMask.layerMaxXMinYCorner,
                CACornerMask.layerMinXMinYCorner,
                CACornerMask.layerMaxXMaxYCorner,
                CACornerMask.layerMinXMaxYCorner)
            rectCorner = UIRectCorner.allCorners
        case .begin:
            maskedCorners = CACornerMask(
                arrayLiteral: CACornerMask.layerMaxXMinYCorner,
                CACornerMask.layerMinXMinYCorner)
            rectCorner = UIRectCorner(rawValue:  (UIRectCorner.topLeft.rawValue) | (UIRectCorner.topRight.rawValue))
        case .end:
            maskedCorners = CACornerMask(
                arrayLiteral: CACornerMask.layerMaxXMaxYCorner,
                CACornerMask.layerMinXMaxYCorner)
            rectCorner = UIRectCorner(rawValue: (UIRectCorner.bottomLeft.rawValue) | (UIRectCorner.bottomRight.rawValue))
        default:
            layer.cornerRadius = 0
            guard #available(iOS 11.0, *) else {
                let size = CGSize(width: 0, height: 0)
                let rectCorner = UIRectCorner(rawValue: 0)
                filletedCorner(size, rectCorner)
                return
            }
            return
        }
        
        if #available(iOS 11.0, *) {
            layer.cornerRadius = cornerRadius
            layer.masksToBounds = true
            layer.maskedCorners = maskedCorners
        } else {
            
            // 这里不设置圆角为0，会被覆盖
            layer.cornerRadius = 0
            // width 为横，height为竖？这个size有点迷
            let size = CGSize(width: cornerRadius, height: 0)
            filletedCorner(size, rectCorner)
        }
    }
    
    /// 设置多个圆角
    ///
    /// - Parameters:
    ///   - cornerRadii: 圆角幅度
    ///   - roundingCorners: UIRectCorner(rawValue: (UIRectCorner.topRight.rawValue) | (UIRectCorner.bottomRight.rawValue))
    public func filletedCorner(_ cornerRadii: CGSize,
                               _ roundingCorners: UIRectCorner)  {
        
        let fieldPath = UIBezierPath.init(roundedRect: bounds, byRoundingCorners: roundingCorners, cornerRadii:cornerRadii )
        let fieldLayer = CAShapeLayer()
        fieldLayer.frame = bounds
        fieldLayer.path = fieldPath.cgPath
        layer.mask = fieldLayer
    }
}