IOS 给表格添加章节和索引 UITableView

 1 import UIKit
 2
 3 class ViewController：UIViewController,UITableViewDataSource {
 4
 5 var countries：Dictionary<String, [String]> = [“A”：
 [“Afghanistan”, “Albania”, “Algeria”, “Angola”, “Australia”,
 “Austria”, “Azerbaijan”], “B”：
 [“Bangladesh”,“Belgium”,“Bhutan”,“Bolivia”,“Brazil”,“Bahrain”,
 “Bulgaria”],“C”：
 [“Canada”,“Congo”,“Chile”,“China”,“Colombia”,“Cuba”],“D”：
 [“Denmark”,“Djibouti”,“Dominica”], “E”：
 [“Egypt”,“Estonia”,“Ethiopia”], “F”：
 [“Fiji”,“Finland”,“France”], “G”：
 [“Gambia”,“Germany”,“Greece”], “H”：
 [“Haiti”,“Honduras”,“Hungary”], “I”：
 [“India”,“Indonesia”,“Iran”,“Ireland”,“Iraq”,“Italy”], “J”：
 [“Jordan”, “Japan”], “K”：[“Kazakhstan”,“Korea”,“Kuwait”],
 “L”：[“Laos”,“Libya”,“Lebanon”], “M”：
 [“Madagascar”,“Morocco”,
 “Malaysia”,“Mexico”,“Mali”,“Mozambique”], “N”：
 [“Nepal”,“Netherlands”,“Nigeria”,“New Zealand”], “O”：
 [“Oman”], “P”：
 [“Pakistan”,“Panama”,“Philippines”,“Portugal”], “Q”：
 [“Qatar”], “R”：[“Romania”,“South Africa”, “Russia”], “S”：
 [“Serbia &
 Montenegro”,“Senegal”,“Singapore”,“Somalia”,“Switzerland”],
 “T”：[“Thailand”, “Turkmenistan”,“Tunisia”,“Turkey”],
 “U”：[“United Arab Emirates”,“United States of America”,
 “Uzbekistan”], “V”：[“Vanuatu”,“Venezuela”,“Vietnam”],
 “Y”：[“Yemen”], “Z”：[“Zambia”,“Zimbabwe”]]
 6
 7 var keys：[String] = []
 8
 9 override func viewDidLoad() {
 10 super.viewDidLoad()
 11 // Do any additional setup after loading the view,
 typically from a nib.
 12
 13 keys = Array(countries.keys).sorted()
 14
 15 let screenRect = UIScreen.main.bounds
 16 let tableRect = CGRect(x：0, y：20, width：
 screenRect.size.width, height：screenRect.size.height - 20)
 17 let tableView = UITableView(frame：tableRect)
 18
 19 tableView.dataSource = self
 20
 21 self.view.addSubview(tableView)
 22 }
 23
 24 func numberOfSections(in tableView：UITableView) ->
 Int {
 25 return keys.count
 26 }
 27
 28 func tableView(_ tableView：UITableView,numberOfRowsInSection section：Int) -> Int{
 29 let subCountries = countries[keys[section]]
 30 return (subCountries？.count)！
 31 }
 32
 33 func tableView(_ tableView：UITableView,
 titleForHeaderInSection section：Int) -> String？{
 34 return keys[section]
 35 }
 36
 37 func sectionIndexTitles(for tableView：UITableView) -
 [String]？{
 38 return keys
 39 }
 40
 41 func tableView(_ tableView：UITableView,
 cellForRowAt indexPath：IndexPath) -> UITableViewCell {
 42
 43 let identifier = “reusedCell”
 44 var cell =
 tableView.dequeueReusableCell(withIdentifier：identifier)
 45
 46 if(cell == nil){
 47 cell = UITableViewCell(style：
 UITableViewCellStyle.default, reuseIdentifier：identifier)
 48 }
 49
 50 let subCountries = countries[keys[(indexPath as
 NSIndexPath).section]]
 51 cell？.textLabel？.text = subCountries！[(indexPath as
 NSIndexPath).row]
 52
 53 return cell！
 54 }
 55 }
 

//索引表格需要用的代理方法