ELReader

06 Apr 2017

Reading time ~2 minutes

ELReader

GitHub demoGif

Requirements

iOS 8.0+
Alamofire / SnapKit / Fuzi / SVProgressHUD
Carthage
Xcode 8.0+
Swift 3.0+

Introduction

从小说网站爬取数据,并展示.使用 UIPageViewController 展示数据.使用 Fuzi解析 XML. 使用了传闭包的方法处理页面跳转,具体请看AppTransfrom.swift.

我觉得这样处理看起来还是比较整洁的.把所有跳转的逻辑都放到了一个类里面,方便管理

BookModel

首先要有一个存储书籍的类作为 model

import Foundation
import Fuzi

//习惯写了协议方便以后嘛
protocol BaseBookProtocol {
    var uri: String {get}
    var name: String {get}
    var category: String {get}
    var author: String? {get}
}
class Book: BaseBookProtocol {
    let uri: String
    let name: String
    //小说分类
    let category: String
    let author: String?
    //当前章节编号
    var currentChapterNumber: Int = 0
    //章节url和章节名称
    var catalogues: [(uri: String, title: String)]?

    init(uri: String, name: String, category: String, author: String? = nil) {
        self.uri = uri
        self.name = name
        self.category = category
        self.author = author
    }
    //获取章节的 url
    func catalogueURL() -> String {
        return "http://www.ybdu.com/xiaoshuo" + self.uri
    }
    // 根据章节数获取文章内容的 url
    func chapterURL(index: Int = -1) -> String {
        if index == -1 {
            return self.chapterURL(index: currentChapterNumber)
        }
        guard let catalogues = self.catalogues, index < catalogues.count else { return "" }
        let catalogue = catalogues[index]
        return "http://m.ybdu.com/xiaoshuo" + self.uri + catalogue.uri
    }
    // 每一章的标题
    func chapterHeader(index: Int = -1) -> String {
        if index == -1 {
            return self.chapterHeader(index: currentChapterNumber)
        }
        guard let catalogues = self.catalogues, index >= catalogues.count else { return "" }
        let catalogue = catalogues[index]
        return catalogue.title
    }
    //根据 alamofire 的数据解析成 book 类
    static func creatBooks(from html: HTMLDocument) -> [Book] {
        return html.css(".list p").bookListFilterMap { (element) -> Book in
            let category = element[0]!.stringValue
            let name = element[1]!.stringValue
            let uri = element[1]!.attr("href")!.replacingOccurrences(of: "/xiazai", with: "")
            let author = element.firstChild(xpath: "text()")?.stringValue.replacingOccurrences(of: "/", with: "")
            return Book(uri: uri, name: name, category: category, author: author)
        }
    }
}

bookListFilterMap这个方法是对 Fuzi NodeSet 的拓展.为了看起来整洁,主要是 filter 和 map 的实现

extension NodeSet
{
    func bookListFilterMap(_ transform: (XMLElement) -> Book ) -> [Book] {
        var result: [Book] = []
        for element in self where element[0] != nil && element[1] != nil {
            result.append(transform(element))
        }
        return result
    }

}

bookList

解决了 model 开始做数据请求了获取排行榜的小说,并用 tableView 展示使用我上次做的 ELSegmentView 来做排行榜的切换.

网络请求使用 alamofire

override func viewDidLoad() {
    super.viewDidLoad()
    self.navigationController?.isNavigationBarHidden = true
    segmentView.titles = ["日排行","周排行","月排行","总排行"]
    segmentView.delegate = self
    tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
    SVProgressHUD.show()
    SVProgressHUD.setDefaultMaskType(.clear)
    Alamofire.request(Router.loadDayList).responseHTMLDocument { [weak self] (response) in
        SVProgressHUD.dismiss(withDelay: 0.4)
        switch response.result {
        case .success(let value):
//                print(value)
            self?.dataSource = Book.creatBooks(from: value)
            self?.tableView.reloadData()
        case .failure(let error):
            print(error)
        }
    }
}

拓展 Alamofire 的 DataRequest 来处理 HTML 的解析

extension DataRequest {

    public static func HTMLResponseSerializer() -> DataResponseSerializer<HTMLDocument> {
        return DataResponseSerializer { request, response, data, error in
            //catch web error
            guard error == nil else {
                return .failure(BackendError.network(error: error!))
            }
            //使用 alamofire 解决 data 的提取
            let result = Request.serializeResponseData(response: response, data: data, error: nil)
            guard case let .success(validData) = result else {
                return .failure(BackendError.dataSerialization(error: result.error! as! AFError))
            }
            //使用 Fuzi 解析 html
            do {
                let html = try HTMLDocument(data: validData)
                return .success(html)
            } catch {
                return .failure(BackendError.xmlSerialization(error: error))
            }
        }

    }
    //解析 HTML
    @discardableResult
    func responseHTMLDocument(queue: DispatchQueue? = nil, completionHandler: @escaping (DataResponse<HTMLDocument>) -> Void) -> Self {
        return response(queue: queue, responseSerializer: DataRequest.HTMLResponseSerializer(), completionHandler: completionHandler)
    }
}