本篇是Swift内部培训整理的PPT材料，主要内容来源于苹果Swift编程语言官方教程，参考了网上的一些视频课程内容。在教程介绍完之后，本人附带实现了一个项目开发中的常用场景的Demo：基于导航栏和Tab栏的应用。
1.Swift概述
我们先来看一篇文章：《苹果新贵 Swift之前世今生》
Swift是用于设计iOS及Mac OS X应用的一门新语言。
1.1.Swift特点
- Swift保留了C与Objective-C的优点，并摒弃其为了兼容C语言所受的限制；
- Swift吸纳了安全编程模式，并新增了一些现代化功能，使其更易使用、更为灵活、更具乐趣。
- Swift的简洁风格与广受欢迎的成熟框架Cocoa/Cocoa Touch相结合，将为重新构思软件的开发过程带来新机遇；
- Swift内存管理采用ARC风格。
1.2.Swift代码的文件扩展名
*.swift
2.第一个Swift程序
2.1.使用Xcode Project编写
2.2.使用Playground编写
我们可以基于 Playground 做这些事情：
- 学习：通过 Playground 学习 Swift，制作 Swift 教程实现交互式学习，同时还可以培训其他初学者。
- 代码开发：执行算法程序，迅速看到算法结果，跟踪变量；执行绘图程序，即时看到图像结果，及时调整。执行通用代码，查看变量的改变情况。
- 实验性代码：无需创建项目，直接打开一个独立的Playground文件即可编写代码，尝试调用新的 API。
3.常量与变量
let关键词声明常量，var关键词声明变量。
let maximumNumberOfLoginAttempts = 10 // 常量只有在初始化的时候可以赋值 var currentLoginAttempt = 0
4.运算符和表达式
4.1.运算符
- 算术运算符：*、/、+、—、%、++、——
- 关系运算符：>、<、>=、<=、==、!=
- 布尔逻辑运算符：！、&&、||
- 三元运算符：？：
4.2.表达式
1.不指定数据类型
var a1 = 10 var a2 = 20 var a = a1 > a2 ? "a1":"a2"
2.指定数据类型
var a1:Int = 10 var a2:Int = 20 var a = a1 > a2 ? "a1":"a2"
3.可以有分号结尾
var a1:Int = 10; var a2:Int = 20 var a = a1 > a2 ? "a1":"a2"
4.3.注释
// /* */
5.数据类型
5.1.整型
Swift提供8、16、32、64位形式的有符号及无符号整数，这些整数类型遵循C语言的命名规约。与Swift中的所有类型一样，这些整数类型的名称以大写字母开头。
Swift还提供了一个整数类型Int；
- 在32位平台，Int与Int32宽度一致；
- 在64位平台，Int与Int64宽度一致；
Swift还提供了无符号整数类型UInt。
5.2.浮点型
- 单精度浮点(32位) Float
- 双精度浮点(64位) Double
5.3.数字型
表示数字如下：
let decimalInteger = 17 // 表示是10进制 let binaryInteger = 0b10001 // 二进制17 let octalInteger = 0o21 // 8进制17 let hexadecimalInteger = 0x11 // 16进制17
5.4.布尔类型
true和false
let orangesAreOrange = true let turnipsAreDelicious = false
6.数据类型转换
6.1.整型转换
不同类型的整数常量或变量所能存储的值域不同，需要显示地转换
let twoThousand:UInt16 = 2000 let one:UInt8 = 1 //let twoThousandAndOne = twoThousand + one // 错误 let twoThousandAndOne = twoThousand + UInt16(one) // 正确
6.2.整型与浮点数转换
整数与浮点数类型之间的转换，需要显示地转换：
let three = 3 let pointOneFourOneFiveNine = 0.14159 let pi = Double(three) + pointOneFourOneFiveNine
7.字符串类型
7.1.字符串初始化
1.初始化
let someString = "Some string literal value" let wiseWords = "\"Imagination is more important than knowledge\" - Einstein" let dollarSign = "\x24" // $,Unicode scalar U+0024
2.空值
var emptyString = "" // 空串初始化 var anotherEmptyString = String() // 通过初始化函数初始化
3.空值判断
if emptyString.isEmpty{
println("Nothing to see here")
}
if emptyString == ""{
println("Nothing to see here")
}
7.2.字符串修改
var 声明的可以修改，let不能修改。
var variableString = "Horse" variableString += " and carriage"
7.3.字符串插入
斜杠+括号+变量
let multiplier = 3 let message = "\(multiplier) times 2.5 is \(Double(multiplier) * 2.5)"
7.4.字符串长度
使用countElements函数。OC中使用length属性。
let unusualMenagerie = "Koala , Snail, Penguin"
println("unusualMenagerie has \(countElements(unusualMenagerie)) characters")
7.5.比较字符串相等
let quotation = "We‘re a lot alike,you and I."
let sameQuotation = "We‘re a lot alike,you and I."
if quotation == sameQuotation{
println("These two strings are considered equal")
}
8.元组(tuple)类型
元组将多个值组合为单个值。元组内的值可以是任意类型，各元素不必是相同的类型，元组在作为函数返回值时尤其有用。
1.定义方法1
let http404Error = (404,"Not Found")
println("The status code is \(http404Error.0)");
println("The status message is \(http404Error.1)");
2.定义方法2
let http200Error = (statusCode:404,discription:"Not Found")
println("The status code is \(http200Error.statusCode)");
println("The status message is \(http200Error.discription)");
9.可选(Optional)类型
9.1.使用可选类型
我们在如下情况下使用可选类型：
- 它有值但不确定；
- 没有任何值。
let possibleNumber = "123" let convertedNumber:Int?=possibleNumber.toInt()
“Int?”是可选类型
if convertedNumber{
println("\(possibleNumber) has an Integer value of \(convertedNumber!)")
}
else{
println("\(possibleNumber) could not be convented to an integer")
}
convertedNumber是从可选类型中取值
9.2.使用nil
我们可以为可选类型的变量设置nil值，表示没有任何值。
var serverResponseCode:Int?=404 serverResponseCode = nil
如果不是可选类型，那么是不能设置为nil的
10.数组
10.1.数组初始化
基本语法：
[value1,value2,value3] var shoppingList:String[] = [“Eggs","Milk"]
对比一下OC中的方式：
NSArray *array = @[@"aa",@"bb"];
10.2.数组追加元素
使用append函数追加或通过+操作符：
var shoppingList:String[] = ["Eggs","Milk"]
shoppingList.append("Flour")
shoppingList += ["Cheese","Butter"]
10.3.数组插入元素
使用insert方法：
var shoppingList:String[] = ["Eggs","Milk"]
shoppingList.insert("Butter", atIndex: 0)
shoppingList += ["Cheese","Chocolate Spread"]
比较一下OC中：
[array insertObject:@"dd" atIndex:1];
10.4.数组删除元素
使用removeAtIndex方法
var shoppingList:String[] = ["Eggs","Milk","Butter"] let deleteItem = shoppingList.removeAtIndex(2) println(deleteItem) println(shoppingList)
10.5.数组长度
使用count属性(和OC中一样)：
var shoppingList:String[] = ["Eggs","Milk","Butter"]
println("The shopping list contains \(shoppingList.count) items.")
10.6.数组遍历
1.遍历方法1
var shoppingList:String[] = ["Eggs","Milk","Butter"]
for item in shoppingList{
println(item)
}
2.遍历方法2
有循环变量：
for(index,value) in enumerate(shoppingList){
println("Item \(index + 1):\(value)")
}
11.字典
11.1.字典初始化
基本语法：
[key1:value1,key2:value2,key3:value3] var airports:Dictionary<String,String> = ["TYO":"Tokyo","DUB":"Dublin"]
11.2.字典追加元素
var airports:Dictionary<String,String> = ["TYO":"Tokyo","DUB":"Dublin"]
airports["LHR"] = "Lonton"
println("The dictionary of airports contains \(airports.count)")
11.3.字典删除元素
通过removeValueForKey(key)方法删除
var airports:Dictionary<String,String> = ["TYO":"Tokyo","DUB":"Dublin"]
if let removedValue = airports.removeValueForKey("DUB"){
println("The removed airport‘s name is \(removedValue)")
}
else{
println("The airports dictionary does not contains a value for DUB")
}
11.4.字典长度
使用count属性
println("The count of airport‘s is \(airports.count)")
11.5.字典遍历
1.遍历字典
var airports:Dictionary<String,String> = ["TYO":"Tokyo","DUB":"Dublin"]
for (airportCode,airportName) in airports{
println("\(airportCode):\(airportName)")
}
2.遍历键和值
for airportCode in airports.keys{
println("Airport code:\(airportCode)")
}
for airportName in airports.values{
println("Airport name\(airportName)")
}
3.获得键和值的数组
let airportCodes = Array(airports.keys) let airportNames = Array(airports.values)
12.控制语句
12.1.分支语句
1.条件语句if-else
if boolean-expression{
statement1;
}[else if boolean-expression{
statement2;
}]
[else{
statement3;
}]
2.多分支语句switch
switch some value to consider{
case value1,value2,value3:
respond to value1
default:
otherwise
}
每个case不需要显示地添加break,每个case至少有一条语句。可以比较任何类型。
12.2.循环语句
1.while语句
while condition{
statements
}
示例：
var i = 100
var r = 0
var s = 0
var t = 0
while i < 1000 {
r = i / 100 ;
s = (i - r * 100) / 10;
t = i - r * 100 - s * 10;
if(i == r * r * r + s * s * s + t * t * t){
println("i=\(i)");
}
i++
}
2.do-while语句
do{
statements
}while condition
示例：
var i = 100
var r = 0
var s = 0
var t = 0
do{
r = i / 100 ;
s = (i - r * 100) / 10;
t = i - r * 100 - s * 10;
if(i == r * r * r + s * s * s + t * t * t){
println("i=\(i)");
}
i++
}while i < 1000
3.for语句
for initialization;condition;increment{
statements
}
示例：
var i = 8
var r = 0
var s = 0
for var j = 0;j <= i;j++ {
r = j * j;
s = j * j * j;
println("\(j)的平方：\(r) \(j)的立方：\(s)");
}
4.for in语句
一般用于遍历集合
1.遍历范围
for index in 1...5{
println("\(index) times 5 is \(index * 5)");
}
2.忽略循环变量
let base = 3
let power = 10
var answer = 1
for _ in 1...power{
answer *= base;
}
println("\(base) to the power of \(power) is \(answer)")
3.遍历数组
let names = ["Anna","Alex","Jack"]
for name in names{
println("Hello,\(name)")
}
4.遍历字典
let numberofLegs = ["spider":8,"ant":6,"car":4];
for(animalName,legCount) in numberofLegs{
println("\(animalName) have \(legCount) legs")
}
5.遍历字符串
for character in "Hello"{
println(character)
}
12.3.跳转语句
- continue：终止当次循环，接着进入下一次循环
- break：终止循环；
- fallthrough：其他语言没有的，贯穿的意思，常用于switch语句中，示例如下：
let integerDescribe = 5
var description = "The number \(integerDescribe) is"
switch integerDescribe{
case 2,3,5:
description += " a prise number,and also"
fallthrough
default:
description += " an integer.";
}
4.return
13.函数
13.1.函数定义
使用func定义一个函数。调用函数使用它的名字加上小括号中的参数列表。使用->分隔参数的名字和返回值类型。
函数声明：
func greet(name:String,day:String) -> String{
return "Hello \(name),today is \(day)"
}
函数调用：
greet("Bob", "Tuesday")
13.2.无返回值函数
func sayGoodBye(personName:String){
println("Goodbye,\(personName)");
}
sayGoodBye("Tony");
13.3.多返回值函数
使用元组类型返回多个值
func count(string:String) -> (vowels:Int,consonants:Int,others:Int){
var vowel = 0,consonant = 0,other = 0;
for character in string{
switch String(character).lowercaseString{
case "a","e","i","o","u":
++vowel;
case "b","c","d","f","g","h","j","k","l","m","n","p","q","r","s","t","v","w","x","y","z":
++consonant;
default:
++other;
}
}
return (vowel,consonant,other);
}
let total = count("Some thing is change!");
println("\(total.vowels)元音,\(total.consonants)辅音")
13.4.嵌入函数
func chooseStepFunction(backwards:Bool) -> (Int) -> Int{
func stepForward(input:Int) -> Int{
return input + 1
}
func stepBackward(input:Int) -> Int{
return input - 1
}
return backwards ? stepBackward : stepForward
}
var currentValue = -4
// moveNearerToZero是一个函数指针
let moveNearerToZero = chooseStepFunction(currentValue > 0)
while currentValue != 0{
println("\(currentValue)......")
currentValue = moveNearerToZero(currentValue)
}
14.闭包(Closure)
语法：
{(parameters) -> return type in
statements
}
示例：数组排序
采用函数实现：
let names = ["Chris","Alex","Ewa","Barry","Daniella"]
func backwards(s1:String,s2:String) -> Bool{
return s1 > s2
}
// sort排序函数，backwards通过排序规则的函数
var reversed = sort(names,backwards)
println(reversed)
采用闭包实现：
var reversed = sort(names,{(s1:String,s2:String) -> Bool in
return s1 > s2
})
println(reversed)
15.类与结构体
类和结构体有很多共性：
- 定义属性存储数据；
- 定义方法执行功能处理；
- 定义下标，通过下标访问它们的值；
- 初始化它们的状态；
- 通过扩展（Extension）扩展其功能；
- 遵守协议(Protocol)，协议提供一种特定的标准功能。
类比结构体多出的功能：
- 能够继承另外一个类；
- 能够核对运行期对象的类型；
- 析构对象释放资源；
- 引用计数允许一个类实例有多个引用。
15.1.类和结构体的定义
定义类和结构体：
class SomeClass{
// class definition goes here
}
struct SomeStructure{
// structure definition goes here
}
示例：
struct Resolution{
var width = 0
var height = 0
}
class VideoMode{
var resolution = Resolution()
var interfaced = false
var frameRate = 0.0
var name:String?
}
15.2.类和结构体的实例化
struct Resolution{
var width = 0
var height = 0
}
class VideoMode{
var resolution = Resolution()
var interfaced = false
var frameRate = 0.0
var name:String?
}
let someResolution = Resolution()
// let someResolution = Resolution(width:10,height:20)
let someVideoMode = VideoMode()
16.属性
16.1.属性的存储
属性的主要作用是存储数据，可以分为常量属性和变量属性；
struct FixedLengthRange{
var firstValue:Int
let length:Int
}
var rangeOfThreeItems = FixedLengthRange(firstValue:0,length:3)
rangeOfThreeItems.firstValue = 6
// 注意：length是常量属性，值是不可以修改的
16.2.延时存储属性
延时存储属性是初始化时候不分配值，直到第一次使用它。属性@lazy声明。
为什么要用延时存储属性？当一个属性是一个庞大类时，并且这个属性很少用到，那么就可以考虑使用延时存储属性，这样可以避免大量数据加载到内存中。
class DataImporter{
var fileName = "data.txt"
}
class DataManager{
@lazy var importer = DataImporter()
var data = ""
}
let manager = DataManager();
manager.data += "Some Data"
manager.data += "Some more data"
println(manager.importer.fileName)
去掉@lazy关键字在playground里面试试，看看有什么不一样？
16.3.计算属性
有的时候一些属性是通过其他的属性计算得出的，通过get和set访问器对其访问。
// 定义Point
struct Point{
var x = 0.0,y = 0.0
}
// 定义Size
struct Size{
var width = 0.0,height = 0.0
}
// 定义Rect
struct Rect{
var origin = Point()
var size = Size()
var center:Point{
get{
let centerX = origin.x + (size.width / 2)
let centerY = origin.y + (size.height / 2)
return Point(x:centerX,y:centerY)
}
set(newCenter){
origin.x = newCenter.x - (size.width / 2)
origin.y = newCenter.y - (size.height / 2)
}
}
}
var square = Rect(origin:Point(x:0.0,y:0.0),size:Size(width:10.0,height:20.0))
let initialSquareCenter = square.center
square.center = Point(x:15.0,y:15.0)
println("square origin is now at (\(square.origin.x),\(square.origin.y))")
16.4.属性观察者
为了监听属性的变化，swift通过了属性观察者。
- willset观察者是在存储之前调用；
- didSet新值存储后调用。
class StepCounter{
var totalSteps:Int = 0{
willSet(newTotalSteps){
println("About to set totalSteps to \(newTotalSteps)")
}
didSet{
if totalSteps >= oldValue{
println("Added \(totalSteps - oldValue) steps")
}
}
}
}
let stepCounter = StepCounter()
stepCounter.totalSteps = 200
stepCounter.totalSteps = 360
16.5.静态属性
静态属性在结构体中使用static定义，类中使用class定义。
struct SomeStructure{
static var storedTypeProperty = "Some Value"
}
class SomeClass{
class var computedTypeProperty:Int{
return 3
}
}
17.方法
Swift中的方法是与特定类型(类和结构体)相关的函数
17.1.方法
class Counter{
var count = 0
func increment(){
count++
}
func incremmentBy(amount:Int){
count += amount
}
func reset(){
count = 0
}
}
let counter = Counter()
counter.increment()
counter.incremmentBy(5)
counter.reset()
17.2.使用self
self代表当前对象。
struct Point{
var x = 0.0,y = 0.0
func isToTheRightOfX(x:Double) -> Bool{
return self.x > x
}
}
let somePoint = Point(x:4.0,y:5.0)
if somePoint.isToTheRightOfX(1.0){
println("This point is to the right of the line where x == 1.0")
}
18.下标
18.1.定义下标
还记得字典吗？
var numberOfLegs = ["bird":2,"cat":4,"ant":6] let birdLeg = numberOfLegs["bird"]
["bird"]就是下标
下标可以在类和结构体中定义
18.2.只读下标
struct TimesTable{
let multiplier:Int
subscript(index:Int) -> Int{
return multiplier * index
}
}
let threeTimesTable = TimesTable(multiplier:3)
println("six times three is \(threeTimesTable[6])")
19.继承
Swift中的类能够继承其他类的属性、方法等。
19.1.定义基类
class Vehicle{
var numberOfWheels:Int
var maxPassengers:Int
func description() -> String{
return "\(numberOfWheels) wheels;up to \(maxPassengers)"
}
init(){
numberOfWheels = 0
maxPassengers = 1
}
}
let someVehicle = Vehicle()
19.2.定义子类
class Bicycle:Vehicle{
init() {
super.init()
numberOfWheels = 2
}
}
let bicycle = Bicycle()
println("Bicycle:\(bicycle.description())")
19.3.重写(Overriding)
子类能够重写父类的方法、属性、下标。
19.3.1方法重写
class Vehicle{
var numberOfWheels:Int
var maxPassengers:Int
func description() -> String{
return "\(numberOfWheels) wheels;up to \(maxPassengers)"
}
init(){
numberOfWheels = 0
maxPassengers = 1
}
}
class Car:Vehicle{
var speed:Double = 0.0
init() {
super.init()
numberOfWheels = 4
maxPassengers = 5
}
override func description() -> String{
return super.description() + ";" + "traveling at \(speed)"
}
}
let car = Car()
println("Car:\(car.description())")
19.3.2属性重写
class Vehicle{
var numberOfWheels:Int
var maxPassengers:Int
func description() -> String{
return "\(numberOfWheels) wheels;up to \(maxPassengers)"
}
init(){
numberOfWheels = 0
maxPassengers = 1
}
}
class Car:Vehicle{
var speed:Double = 0.0
init() {
super.init()
numberOfWheels = 4
maxPassengers = 5
}
override func description() -> String{
return super.description() + ";" + "traveling at \(speed)"
}
}
class SpeedLimitedCar:Car{
override var speed:Double{
get{
return super.speed
}
set{
super.speed = min(newValue,40.0)
}
}
}
let limitedCar = SpeedLimitedCar()
limitedCar.speed = 60.0
println("SpeedLimitedCar:\(limitedCar.description())")
20.构造器(Initializer)
为了初始化结构体和类等类型的实例属性。
20.1.默认构造器
struct Fahrenheit{
var temperature:Double
init(){
temperature = 32.0
}
}
var f = Fahrenheit() // 调用默认构造器init()，没有参数和返回值
println("The default temperature is \(f.temperature)")
20.2.自定义构造器
定义类两个构造器：init(fromFahrenheit:) 和 init(fromKelvin:)
struct Celsius{
var temperatureInCelsius:Double
init(fromFahrenheit fahrenheit:Double){
temperatureInCelsius = (fahrenheit - 32.0) / 1.8
}
init(fromKelvin kelvin:Double){
temperatureInCelsius = kelvin - 273.15
}
// init(fahrenheit:Double){
// temperatureInCelsius = (fahrenheit - 32.0) / 1.8
// }
//
// init(kelvin:Double){
// temperatureInCelsius = kelvin - 273.15
// }
}
let boilingPointOfWater = Celsius(fromFahrenheit:212.0)
let freezingPointOfWater = Celsius(fromKelvin:273.15)
//let boilingPointOfWater = Celsius(fahrenheit:212.0)
//let freezingPointOfWater = Celsius(kelvin:273.15)
21.析构器(Deinitializer)
析构器与构造器相反，在对象释放时候调用。
使用关键字deinit，语法如下：
deinit{
}
实例：
class Player{
var coinsInPurse:Int
init(coins:Int){
println("call init")
coinsInPurse = coins
}
func winCoins(coins:Int){
coinsInPurse += 10
}
deinit{
coinsInPurse = 0
}
}
var playerOne:Player? = Player(coins:100)
println("PlayerOne has coins \(playerOne!.coinsInPurse)")
playerOne = nil;
22.扩展(Extension)
在现有类和结构体的基础上，扩展新的功能。
语法：
extension SomeType{
}
extension SomeType:SomeProtocol,AnotherProtocol{
}
OC中的扩展：
@interface UIImage (UIImageScale)
22.1.计算属性
extension Double{
var km:Double{return self * 1000.0}
var m:Double{return self}
var cm:Double{return self / 100.0}
var mm:Double{return self / 1000.0}
}
let oneInch = 25.4.mm
println("OneInch is \(oneInch) meters")
22.2.使用构造器
struct Size{
var width = 0.0,height = 0.0
}
struct Point{
var x = 0.0,y = 0.0
}
struct Rect{
var origin = Point()
var size = Size()
}
extension Rect{
init(center:Point,size:Size){
let originX = center.x - (size.width / 2)
let originY = center.y - (size.height / 2)
self.init(origin:Point(x:originX,y:originY),size:size)
}
}
let centerRect = Rect(center:Point(x:4.0,y:4.0),size:Size(width:3.0,height:3.0))
22.3.方法扩展
extension Int{
func message() -> String{
var message = "";
switch self{
case 0:
message = "成功"
case -1:
message = "用户登录失败"
default:
message = "未知错误"
}
return message;
}
}
3.message();
0.message();
(-1).message();
23.协议(Protocol)
协议是为方法、属性等定义一套规范，没有具体的实现。协议能够被类、结构体等具体实现。
protocol SomeProtocol{
}
struct SomeStructure:SomeProtocol{
}
class SomeClass:SomeProtocol{
}
23.1.属性
// 1.set和get访问器
protocol SomeProtocol{
var mustBeSettable:Int{get set}
var doesNotNeedToBeSettable:Int{get}
}
// 2.静态属性
protocol AnotherProtocol{
class var someTypeProperty:Int{get set}
}
// 3.只读
protocol FullyNamed{
var fullName:String{get}
}
示例：
protocol FullyNamed{
var fullName:String{get}
}
struct Person : FullyNamed{
var fullName:String
}
let john = Person(fullName:"John Appleseed")
class Starship : FullyNamed{
var prefix:String?
var name:String
init(name:String,prefix:String? = nil){
self.name = name
self.prefix = prefix
}
var fullName:String{
return (prefix ? prefix! + " " : "") + name
}
}
var ncc1701 = Starship(name:"Enterprise",prefix:"USS")
println("\(ncc1701.fullName)")
23.2.方法
// 1.定义方法
protocol RandomNumberGenerator{
func random() -> Double
}
// 2.定义静态方法
protocol SomeProtocol{
class func someTypeMethod()
}
示例：
class LinearCongruentialGenerator:RandomNumberGenerator{
var lastRandom = 42.0
let m = 139968.0
let a = 3877.0
let c = 29573.0
func random() -> Double{
lastRandom = ((lastRandom * a + c) % m)
return lastRandom / m
}
}
let generator = LinearCongruentialGenerator()
println("Here‘s a random number:\(generator.random())")
23.3.把协议作为类型使用
protocol RandomNumberGenerator{
func random() -> Double
}
class LinearCongruentialGenerator:RandomNumberGenerator{
var lastRandom = 42.0
let m = 139968.0
let a = 3877.0
let c = 29573.0
func random() -> Double{
lastRandom = ((lastRandom * a + c) % m)
return lastRandom / m
}
}
class Dice{
let sides:Int
let generator:RandomNumberGenerator
init(sides:Int,generator:RandomNumberGenerator){
self.sides = sides
self.generator = generator
}
func roll() -> Int{
return Int(generator.random() * Double(sides)) + 1
}
}
var d6 = Dice(sides:6,generator:LinearCongruentialGenerator())
for _ in 1...5{
println("Random dice roll is \(d6.roll())")
}
24.Swift的应用
在这一部分，我实现了一个小Demo：导航栏和Tab栏结合使用。具体代码说明如下：
24.1.项目结构说明
主要文件说明：
- AppDelegate：系统委托类；
- TabBarViewController：Tab栏管理类；
- CustomNavigationController：自定义的导航栏类，在这个类里面，做了4英寸屏和3.5英寸屏的处理；
- ViewController文件夹：具体的页面控制器；
- NSStringExt：对String类型的扩展，主要是IOS7的判断、根据字符串长度返回在控件中显示的高度(常用于UITableViewCell中自适应调整Cell的高度使用)；
- .......
24.2.运行效果截图
iPhone 5S截图：
iPhone 4S截图：
24.3.主要代码
AppDelegate里面：
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool
{
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
var tabbarViewCtrl = TabBarViewController(nibName:nil,bundle:nil);
// var navigationViewController = UINavigationController(rootViewController:tabbarViewCtrl);
var navigationViewController = CustomNavigationController(rootViewController: tabbarViewCtrl);
self.window!.rootViewController = navigationViewController;
self.window!.makeKeyAndVisible()
return true
}
TabBarViewController：
init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: NSBundle?)
{
super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
self.title = "任务";
}
override func viewDidLoad()
{
super.viewDidLoad()
configureTabBar();
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/*******************************************************************************
* 方法名称：configureTabBar
* 功能描述：配置TabBar控件
* 输入参数：
* 输出参数：
******************************************************************************/
func configureTabBar()
{
self.view.backgroundColor = UIColor.whiteColor();
self.tabBar.hidden = true; // 隐藏自带的Tab
var width = self.view.frame.size.width;
var height = self.view.frame.size.height;
self.myTabbar = UIView(frame:CGRectMake(0, height - 48 - 64, width, 112));
let currentVersion = UIDevice.currentDevice().systemVersion;
if (currentVersion.isIos7())
{
self.myTabbar!.frame = CGRectMake(0, height - 48, width, 112);
}
self.myTabbar!.backgroundColor = UIColor(patternImage:UIImage(named:"tab_bg_ico.png"));
self.view.addSubview(self.myTabbar);
self.view.bringSubviewToFront(self.myTabbar);
// 任务
var btnTask = UIButton.buttonWithType(UIButtonType.Custom) as UIButton; // 后面必须要加上as UIButton
btnTask.frame = CGRectMake(0, 0, 80, 48);
btnTask.tag = 100;
btnTask.selected = true;
btnTask.setImage(UIImage(named:"tabtask_sel_ico.png"),forState:UIControlState.Normal);
btnTask.addTarget(self,action: "tabBarButtonClicked:",forControlEvents:UIControlEvents.TouchUpInside);
self.myTabbar!.addSubview(btnTask);
// 单据
var btnBill = UIButton.buttonWithType(UIButtonType.Custom) as UIButton;
btnBill.frame = CGRectMake(80, 0, 80, 48);
btnBill.tag = 101;
btnBill.setImage(UIImage(named:"tabbill_nor_ico.png"),forState:UIControlState.Normal);
btnBill.addTarget(self,action: "tabBarButtonClicked:",forControlEvents:UIControlEvents.TouchUpInside);
self.myTabbar!.addSubview(btnBill);
// 查询
var btnQuery = UIButton.buttonWithType(UIButtonType.Custom) as UIButton;
btnQuery.frame = CGRectMake(160, 0, 80, 48);
btnQuery.tag = 102;
btnQuery.setImage(UIImage(named:"tabquery_nor_ico.png"),forState:UIControlState.Normal);
btnQuery.addTarget(self,action: "tabBarButtonClicked:",forControlEvents:UIControlEvents.TouchUpInside);
self.myTabbar!.addSubview(btnQuery);
// 设置
var btnSetting = UIButton.buttonWithType(UIButtonType.Custom) as UIButton;
btnSetting.frame = CGRectMake(240, 0, 80, 48);
btnSetting.tag = 103;
btnSetting.setImage(UIImage(named:"tabset_nor_ico.png"),forState:UIControlState.Normal);
btnSetting.addTarget(self,action:"tabBarButtonClicked:",forControlEvents:UIControlEvents.TouchUpInside);
self.myTabbar!.addSubview(btnSetting);
var taskViewCtrl = MyTaskViewController(nibName:"MyTaskViewController",bundle:nil);
var billViewCtrl = MyBillViewController();
var queryViewCtrl = QueryViewController(nibName:"QueryViewController",bundle:nil);
var settingViewCtrl = SettingViewController(nibName:"SettingViewController",bundle:nil);
self.viewControllers = [taskViewCtrl,billViewCtrl,queryViewCtrl,settingViewCtrl];
}
/*******************************************************************************
* 方法名称：configureTabBar
* 功能描述：配置TabBar控件
* 输入参数：
sender:事件源
* 输出参数：
******************************************************************************/
func tabBarButtonClicked(sender:UIButton)
{
var index = sender.tag;
var btnTask = self.view.viewWithTag(100) as UIButton
var btnBill = self.view.viewWithTag(101) as UIButton
var btnQuery = self.view.viewWithTag(102) as UIButton
var btnSetting = self.view.viewWithTag(103) as UIButton
switch index{
case 100: // 任务
self.title = "任务";
btnTask.selected = true;
btnBill.selected = false;
btnQuery.selected = false;
btnSetting.selected = false;
btnTask.setImage(UIImage(named:"tabtask_sel_ico.png"),forState:UIControlState.Normal);
btnBill.setImage(UIImage(named:"tabbill_nor_ico.png"),forState:UIControlState.Normal);
btnQuery.setImage(UIImage(named:"tabquery_nor_ico.png"),forState:UIControlState.Normal);
btnSetting.setImage(UIImage(named:"tabset_nor_ico.png"),forState:UIControlState.Normal);
case 101: // 单据
self.title = "单据";
btnTask.selected = false;
btnBill.selected = true;
btnQuery.selected = false;
btnSetting.selected = false;
btnTask.setImage(UIImage(named:"tabtask_nor_ico.png"),forState:UIControlState.Normal);
btnBill.setImage(UIImage(named:"tabbill_sel_ico.png"),forState:UIControlState.Normal);
btnQuery.setImage(UIImage(named:"tabquery_nor_ico.png"),forState:UIControlState.Normal);
btnSetting.setImage(UIImage(named:"tabset_nor_ico.png"),forState:UIControlState.Normal);
case 102: // 查询
self.title = "查询";
btnTask.selected = false;
btnBill.selected = false;
btnQuery.selected = true;
btnSetting.selected = false;
btnTask.setImage(UIImage(named:"tabtask_nor_ico.png"),forState:UIControlState.Normal);
btnBill.setImage(UIImage(named:"tabbill_nor_ico.png"),forState:UIControlState.Normal);
btnQuery.setImage(UIImage(named:"tabquery_sel_ico.png"),forState:UIControlState.Normal);
btnSetting.setImage(UIImage(named:"tabset_nor_ico.png"),forState:UIControlState.Normal);
case 103: // 设置
self.title = "设置";
btnTask.selected = false;
btnBill.selected = false;
btnQuery.selected = false;
btnSetting.selected = true;
btnTask.setImage(UIImage(named:"tabtask_nor_ico.png"),forState:UIControlState.Normal);
btnBill.setImage(UIImage(named:"tabbill_nor_ico.png"),forState:UIControlState.Normal);
btnQuery.setImage(UIImage(named:"tabquery_nor_ico.png"),forState:UIControlState.Normal);
btnSetting.setImage(UIImage(named:"tabset_sel_ico.png"),forState:UIControlState.Normal);
default:
println("No Selected Items");
}
self.selectedIndex = index - 100;
}
CustomNavigationController：
class CustomNavigationController: UINavigationController
{
init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: NSBundle?)
{
super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
// Custom initialization
}
init(rootViewController: UIViewController!)
{
return super.init(rootViewController: rootViewController);
}
override func viewDidLoad()
{
super.viewDidLoad()
let currentVersion = UIDevice.currentDevice().systemVersion;
if (currentVersion.isIos7())
{
self.navigationBar.setBackgroundImage(UIImage(named:"navbg_ico.png").stretchableImageWithLeftCapWidth(20,topCapHeight: 30),forBarMetrics:UIBarMetrics.Default);
}
else
{
self.navigationBar.setBackgroundImage(UIImage(named:"navbg_ico.png"),forBarMetrics:UIBarMetrics.DefaultPrompt);
}
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func pushViewController(viewController: UIViewController!, animated: Bool)
{
super.pushViewController(viewController,animated:animated);
}
override func popViewControllerAnimated(animated: Bool) -> UIViewController!
{
return super.popViewControllerAnimated(animated);
}
}
MyTaskViewController
override func viewDidLoad()
{
super.viewDidLoad()
self.tableView.registerClass(UITableViewCell.self,forCellReuseIdentifier: "Cell");
}
override func viewWillAppear(animated: Bool)
{
var width = self.view.frame.size.width
var height = self.view.frame.size.height
self.tableView.frame = CGRectMake(0, 0, width, height - 48);
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// =========================================================================
// Table view data source
func numberOfSectionsInTableView(tableView: UITableView!) -> Int
{
return 1;
}
func tableView(tableView: UITableView!, numberOfRowsInSection section: Int) -> Int
{
return 50;
}
func tableView(tableView: UITableView!, heightForRowAtIndexPath indexPath: NSIndexPath!) -> CGFloat
{
return 56;
}
func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell!
{
let cell = tableView .dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell;
var lblBillCode = UILabel(frame:CGRectMake(10,4,140,22));
lblBillCode.text = "JTBX1404020601";
lblBillCode.font = UIFont(name: "Arial",size: 16);
cell.addSubview(lblBillCode);
var lblContent = UILabel(frame:CGRectMake(160,4,150,22));
lblContent.text = "市内交通费用报销单";
lblContent.textAlignment = NSTextAlignment.Right;
lblContent.font = UIFont(name: "Arial",size: 16);
cell.addSubview(lblContent);
var lblTime = UILabel(frame:CGRectMake(160,30,150,22));
lblTime.text = "2014-05-23 22:10:10";
lblTime.font = UIFont(name: "Arial",size: 14);
lblTime.textColor = UIColor.grayColor();
lblTime.textAlignment = NSTextAlignment.Right;
cell.addSubview(lblTime);
return cell;
}
// =========================================================================
// Table view data delegate
func tableView(tableView: UITableView!, didSelectRowAtIndexPath indexPath: NSIndexPath!){
println("row = %d",indexPath.row)
}
NSStringExt：
extension String {
/*******************************************************************************
* 方法名称：isIos7
* 功能描述：配置TabBar控件
* 输入参数：
* 输出参数：true:IOS7及以上系统;false:IOS7以下系统。
******************************************************************************/
func isIos7() -> Bool?
{
return self >= "7.0"
}
func stringHeightWith(fontSize:CGFloat,width:CGFloat)->CGFloat
{
var font = UIFont.systemFontOfSize(fontSize)
var size = CGSizeMake(width,CGFLOAT_MAX)
var paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.lineBreakMode = .ByWordWrapping;
var attributes = [NSFontAttributeName:font,
NSParagraphStyleAttributeName:paragraphStyle.copy()]
var text = self as NSString
var rect = text.boundingRectWithSize(size, options:.UsesLineFragmentOrigin, attributes: attributes, context:nil)
return rect.size.height
}
}
Swift培训
时间： 2024-10-11 12:57:32