Swift系列之——UISearchBar的简单使用

本篇博客的语法适用于Swift3.0以上。

UISearchBar是一个苹果自带的搜索条，由一个文本框和几个按钮组成，当用户在文本框内输入部分内容之后，程序即可按照指定的规则执行搜索。

下面是UISearchBar的长相：

////  ViewController.swift//  UISearchBarTest////  Created by Mac on 2017/8/4.//  Copyright © 2017年 Jing. All rights reserved.//import UIKitclass ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource, UISearchBarDelegate {    var tableArray: NSArray = ["UI",                               "UIView",                               "View",                               "ViewController",                               "Controller",                               "UIViewController",                               "Search",                               "UISearchBar",                               "Swift"]    var searchArray: NSArray = []    var isSearch = false//默认在非搜索状态下    override func viewDidLoad() {        super.viewDidLoad()        // Do any additional setup after loading the view, typically from a nib.        self.tableView.tableHeaderView = self.searchBar;        self.view.addSubview(tableView);    }    override func didReceiveMemoryWarning() {        super.didReceiveMemoryWarning()        // Dispose of any resources that can be recreated.    }    //使用懒加载方式来创建UITableView    lazy var tableView: UITableView = {        let tempTableView = UITableView (frame: self.view.bounds, style: UITableViewStyle.plain)        tempTableView.delegate = self        tempTableView.dataSource = self        tempTableView.tableFooterView = UIView.init()        return tempTableView    }()    //使用懒加载方式来创建UISearchBar    lazy var searchBar: UISearchBar = {        let tempSearchBar = UISearchBar(frame:CGRect(x: 0, y: 64, width: self.view.bounds.size.width, height: 40))//        tempSearchBar.prompt = "查找图书";        tempSearchBar.placeholder = "请输入搜索关键字";        tempSearchBar.showsCancelButton = true;        tempSearchBar.delegate = self        return tempSearchBar    }()    //根据输入的关键字来过滤搜索结果    func filterBySubstring(filterStr: NSString!) {        isSearch = true        let predicate = NSPredicate(format: "SELF CONTAINS[c] %@", filterStr)        searchArray = tableArray.filtered(using: predicate) as NSArray        tableView.reloadData()    }    //MARK: UITableViewDelegate    func numberOfSections(in tableView: UITableView) -> Int {        return 1    }    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {        if isSearch {            return searchArray.count        }        else{            return tableArray.count        }    }    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {        let identifier = "cellId"        var cell = tableView.dequeueReusableCell(withIdentifier: identifier)        if cell == nil {            cell = UITableViewCell.init(style: UITableViewCellStyle.default, reuseIdentifier: identifier)        }        let row = indexPath.row        if isSearch {            cell?.textLabel?.text = searchArray[row] as? String        }        else{            cell?.textLabel?.text = tableArray[row] as? String        }        return cell!    }    //MARK: UISearchBarDelegate    func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {        isSearch = false        searchBar.resignFirstResponder()        tableView.reloadData()    }    func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {        filterBySubstring(filterStr: searchBar.text! as NSString)    }    func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {        filterBySubstring(filterStr: searchText as NSString)    }}