Swift下tableview/scrollview/colle

废话不说, 上图看效果

QQ20171122-142323@2x.png

实现思路:
为UIScrollVIew写一个分类, 在分类里提供显示和隐藏空白页占位图的功能, 并提供文本点击回调的方法
全部代码:

//  Created by 李大宽 on 2017/11/20.
//  Copyright © 2017年 李大宽. All rights reserved.
//
import UIKit

// 点击代理
protocol EmptyViewDelegate: NSObjectProtocol {
    /** 点击了文本 */
    func didClickedText()
}

private var empty_component_key: UInt8 = 25
private var delegate_key: UInt8 = 98

extension UIScrollView {
    // component view
    var component: EmptyComponent? {
        set {
            objc_setAssociatedObject(self, &empty_component_key, newValue, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
        get {
            return (objc_getAssociatedObject(self, &empty_component_key) as? EmptyComponent)
        }
    }
    
    // delegate
    weak var empty_delegate: EmptyViewDelegate? {
        set {
            objc_setAssociatedObject(self, &delegate_key, newValue, objc_AssociationPolicy.OBJC_ASSOCIATION_ASSIGN)
        }
        get {
            return objc_getAssociatedObject(self, &delegate_key) as? EmptyViewDelegate
        }
    }
    
    /** image 提示图片(可不填) info 提示信息(可不填)*/
    public func configEmptyPage(image: UIImage?=nil,
                                info: String?=nil) {
        if component == nil {
            component = EmptyComponent(frame: self.bounds)
            if component?.superview == nil {
                addSubview(component!)
                bringSubview(toFront: component!)
            }
        }
        component?.isHidden = true
        component?.info_button.addTarget(self, action: #selector(info_button_action(sender:)), for: .touchUpInside)
        component?.backgroundColor = backgroundColor
        component?.note_pic.image = image
        component?.info_button.setTitle(info, for: .normal)
        component?.resetConstraints()
    }
    // 显示
    public func showEmptyPage(){
        component?.isHidden = false
        self.isScrollEnabled = false
    }
    // 隐藏
    public func dismissEmptyPage() {
        component?.isHidden = true
        self.isScrollEnabled = true
    }
    
    ///
    /// delegate action
    @objc func info_button_action(sender: UIButton) {
        empty_delegate?.didClickedText()
    }
    
}

// 内容视图
class EmptyComponent: UIView {
    
    // 设置控件大小
    fileprivate func resetConstraints() {
        // constraints
        if note_pic.image == nil {
            note_pic.bounds = CGRect.zero
        } else if note_pic.image?.size != CGSize.zero {
            note_pic.bounds = CGRect.init(origin: CGPoint.zero, size: (note_pic.image?.size)!)
        }
        note_pic.center = CGPoint.init(x: frame.midX, y: frame.midY-100)
        
        info_button.bounds = CGRect.init(origin: CGPoint.zero, size: CGSize.init(width: frame.maxX, height: 20))
        info_button.center = CGPoint.init(x: frame.midX, y: note_pic.frame.maxY+20)
    }
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        addSubview(note_pic)
        addSubview(info_button)
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    // 提示图片
    lazy var note_pic: UIImageView = {
        let note = UIImageView()
        return note
    }()
    // 按钮
    lazy var info_button: UIButton = {
        let button = UIButton(type: .custom)
        button.setTitleColor(#colorLiteral(red: 0.2549019754, green: 0.2745098174, blue: 0.3019607961, alpha: 1), for: .normal)
        button.titleLabel?.font = UIFont.systemFont(ofSize: 14)
        return button
    }()
}

真实使用案例:

  // view did appear
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        if dataArr.isEmpty {
            startNetwork()
        }
        
        // empty view
        tableView.configEmptyPage(image: #imageLiteral(resourceName: "empty_placeholder_net_error.png"), info: "网络故障 点击重试")
        tableView.empty_delegate = self
        
        
        
        // 在网络请求失败的地方写上这句, 显示空白页
        tableView.showEmptyPage()
    }
    
    func didClickedText() {
        tableView.dismissEmptyPage()
    }

代码总量总共就几十行, 非常简单快捷

如需源码可留下邮箱.