learning swift pdf

, declare the struct body and the type method of the enumeration, and precede the Func keyword of the method with the keyword static. Note: In Objective-c, you can only define type methods (Type-level methods) for objective-c classes. In Swift, you can define type methods for all classes, structs, and enumerations: Each type method is called explicitly by its supported type, with the same type method as the instance method, in point syntax.class SomeC

a copy of HD, not HD itself. Although HD and cinema have the same wide (width) and high (height) properties, they are two completely different instances in the background.　　Class is a reference typeUnlike a value type, a reference type is assigned to a variable, a constant, or is passed to a function, and the operation is not a copy of it. Therefore, referring to an existing instance itself instead of its copy　　Identity operatorBecause a class is a reference type, there may be multiple constant

"Hello World" and do the output. You can see that the expected output appears on the right. 。 (5) Playground also has a very good hint effect, in the output right there is a small eye, click on the eye, you can enlarge the display in another window. 。 (6) On the right side of the small eyes there is a plus, click the plus sign, you can be prompted to output the results below the code. It can be seen that playground is really fun. As shown in the figure: 。 Start

Classes, structs, and enumerations can define subscripts, and he can quickly and easily access the elements of a collection (set,array,dict), and you can make use of subscripts to get and set the collection elements. You can define multiple subscripts for a type, which can be overloaded by the different index value types, and the number of indexed values may be multiple.GrammarLook at an example firstSubscript (index:int), Int { get { // return an appropriate Subscript valuehere }

original articles, welcome reprint. Reprint Please specify: Dongsheng's blog Swift 2.0 in the Print function has 4 kinds of overloaded forms: Print (_:). Output a variable or constant to the console, and wrap the line. print (_:_:). Outputs a variable or constant into a stream of the specified type, and wraps the line. print (_:appendnewline:) Output variable or constant to the console, appendnewline true represents a newline,

If you want to make a custom configuration, you can inherit the base class UIView.The map app needs to touch multiple touch more.Opaque non-transparentHidden hidden, such as the download of the progress bar, if downloaded, you can set this property to make the progress bar disappearClears graphics context If a view needs to update the content, you can check this property by clearing the previous contentClip Subview truncate the child view boundary if the child view of a view is a button, but thi

[Swift learning] Swift programming tour-collection type Dictionaries (8), swiftdictionaries A dictionary is a storage that stores multiple types of data. Each value is associated with a unique key as the identifier of the value data in the dictionary. Unlike the data items in the array, the data items in the dictionary are not in specific order. Dictionary writin

Maplesyrup = Shoppinglist.removeatindex (0)// the item is at Index 0 have just been Removed// shoppinglist now contains 6 items, and no Maple syrup// the Maplesyrup cons Tant is now equal to the removed "Maple syrup" string "If you delete the last piece of data in the array, you should use Removelast () instead of Removeatindex () because it does not have to query the length of the array.　　Iv. Traversal of arraysYou can use the for-in ' loop to iterate through the array. for inch shoppinglist

??Swift 2.0 Learning notes-my first line Swift Codewhen I first saw the following code, I petrified, what is the code? The words spelled out? Import Foundation var str = "HelloWorld" print (str) dizzy, okay, keep your head down and look down, oh, yes.The first sentence: Import Foundationrepresents the introduction Foundation Framework. What is the Foundat

Swift 2.0 Learning notes-my first line of Swift codewhen I first saw the following code, I petrified, what is the code? The words spelled out? Import Foundation var str = "Hello World" print (str) Dizzy, okay, keep your head down and look down, oh, yes.First sentence:import Foundation Represents the introduction of the foundation frame. What is fou

-swift-container-auditor.service Openstack-swift-container-replicator.service openstack-swift-container-updater.servicesystemctl start OpenStack-swift-container.service Openstack-swift-container-auditor.service Openstack-swift-con

using the Romeoandjuliet array:var act1scenecount = 0 for scene in romeoandjuliet { if Scene.hasprefix ("Act 1") { + +act1scenecount }} println ("There is \ (Act1scenecount) scenes in Act 1" Similarly, the Hassuffix method can be used to calculate the number of scenes that occur in and around Capulet mansions and Lawrence cells.var mansioncount = 0 var cellcount = 0 for scene in romeoandjuliet { if Scene.hassuffix ("Capulet ' s Mansion") { + +Mansioncount }

(item)}For (index, value) in Studentlist.enumerate () {Print ("Item \ (index + 1): \ (value)")}The results of the operation are as follows:TomJohn doeHarryItem 1: Zhang SanItem 2: John DoeItem 3: HarryWelcome to follow Dongsheng Sina Weibo @tony_ Dongsheng.Learn about the latest technical articles, books, tutorials and information on the public platform of the smart Jie classroomMore Products iOS, Cocos, mobile design courses please pay attention to the official website of Chi Jie Classroom: ht

Programmers are often thought of as stiff, nerdy, and confused. But sometimes, we can use our own skills to express our romantic. Because the swift language is Unicode-encoded, Unicode has the latest support for emoji (emoji) emoticons. So, I think, can we use swift+unicode for romance?Nonsense not to say, directly on the code:Let love = "xxx, I \u{1f491}\u{1f492}\u{1f493}\u{1f495}\u{1f496}\u{1f497}\u{1f498

normal option to determine whether it contains values: if assumedString { println(assumedString)}// prints "An implicitly unwrapped optional string.You can also use the implicit resolution option in the optional binding to check and parse its value: if let definiteString = assumedString { println(definiteString)}// prints "An implicitly unwrapped optional string. Note: If a variable may become nil, do not use implicit parsing. If you need to determine whether it is nil in the life cycle o

. Learn about the latest technical articles, books, tutorials and information on the public platform of the smart Jie classroom650) this.width=650; "title=" 00.png "src=" http://s2.51cto.com/wyfs02/M01/7C/F2/ Wkiom1bdaioim7h9aaas2mbeznc970.png "alt=" Wkiom1bdaioim7h9aaas2mbeznc970.png "/>More ProductsIOS,Cocos, mobile Design course please pay attention to the official website of Chi Jie Classroom:http://www.zhijieketang.comSmart-Jie Classroom Forum Website:http://51work6.com/forum.phpThis articl

Procedural apes are often thought to be stiff. House, puzzled amorous feelings of a bunch of people. But sometimes. We can also use our own skills to express our romantic.Because the swift language is Unicode-encoded, Unicode has the latest support for emoji (emoji) emoticons. So, I think. Can we use Swift+unicode to get a romantic?Nonsense not to say, directly on the code:Let love = "xxx, I \u{1f491}\u{1f4

useful when compared to a value that returns only one type.Optional (Optional)Use the optional optional to handle some missing value cases.There is a value, and it equals X has an equal to XOR ORThere isn ' t a value at all No valuesAttention:There is no alternative to this concept in the C and Objective-c languages. The closest objective-c feature is that a method either returns an object or returns Nil,nil to indicate "a valid object is missing." However, this only works on objects--for struc

maxinputlevelforallchannels, which is used to represent the maximum value of the level value of all Audiochannel instances, with an initial value of 0.Audiochannel also defines an instance store property named CurrentLevel, which represents the current level value of the channel, with a value of 0 to 10. The CurrentLevel property contains the Didset property monitor to check the value of the property after each new setting, with the following two checks: If the new value of CurrentLevel is grea

Original articles, welcome reprint. Reprint Please specify: Dongsheng's BlogSwift 2.0 in the Print function has 4 kinds of overloaded forms: Print (_:). Output a variable or constant to the console, and wrap the line. print (_:_:). Outputs a variable or constant into a stream of the specified type, and wraps the line. print (_:appendnewline:). Output variable or constant to the console, theappendnewline parameter is a Boolean value,true indicates a newline, andfalse means no line break