protocols

问题 I've researched and researched and still don't understand why shouldStartLoadWithRequest is never called. My page loads fine and some of the UIWebview delegate protocol methods are called. Please find relevant snippets from my code below: Synthesize my webview in my .m (defined in a header file): @implementation PortViewController @synthesize WebView = myWebView; I load my webview successfully: myURLString = [NSString stringWithFormat:@"https://%@", defaultWebsite]; myURL = [NSURL

问题 I was recently reading Protocols, Generic Type Constraints and Arrays in Swift. My question concerns the following two examples from the blog: The code: protocol MyProtocol1 { var myValue: Self { get } } let array: [MyProtocol1] = [] // Error. Produces the error: Protocol 'MyProtocol1' can only be used as a generic constraint because it has Self or associated type requirements. That's expected and there have been several SO questions concerning the topic. However, by changing myValue to a

问题 Some code I inherited has an annoying warning. It declares a protocol and then uses that to specify the delegate @protocol MyTextFieldDelegate; @interface MyTextField: UITextField @property (nonatomic, assign) id<MyTextFieldDelegate> delegate; @end @protocol MyTextFieldDelegate <UITextFieldDelegate> @optional - (void)myTextFieldSomethingHappened:(MyTextField *)textField; @end Classes which use myTextField implement the MyTextFieldDelegate and are called it with this code: if ([delegate

问题 I count 9 HTTP request methods: GET HEAD POST PUT DELETE CONNECT OPTIONS TRACE PATCH The above from: https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods Is that it? will this ever change? 回答1: Registry The HTTP 1.1 spec defines an Hypertext Transfer Protocol (HTTP) Method Registry. As of 2017-01, shows 39 entries: ACL BASELINE-CONTROL BIND CHECKIN CHECKOUT CONNECT COPY DELETE GET HEAD LABEL LINK LOCK MERGE MKACTIVITY MKCALENDAR MKCOL MKREDIRECTREF MKWORKSPACE MOVE OPTIONS ORDERPATCH

问题 So I was thinking about a custom pattern in my project, but I can't get it to work. The main idea is to change the typealias on every subclass to get access to the subclass specific interface. protocol InstanceInterface: class { typealias Interface var interface: Interface { get } } // Baseclass protocol FirstClassInterface: class { /* nothing here for the example */ } class FirstClass: InstanceInterface, FirstClassInterface { typealias Interface = FirstClassInterface var interface: Interface

问题 First, I have a protocol that defines only a few, readonly properties, ex: protocol Example { var var1:String { get } var varArray:[String] { get } } I then want to create a struct that conforms to that protocol. The problem I'm running into, is that I have two conflicting requirements: The properties need to be lazily generated. The properties are related and need to be generated together. I can't seem to find a way to do this. The closest I've come is something like this: struct AStruct :

问题 Lately, I was looking at some Python idioms. I found many descriptions of protocols used in Python, such as the ordering ( __cmp__ , ...) or generators. Besides, there are also methods like __hash__ which are defined for every object (I suppose). After some search on the internet, I haven't found a comprehensive list of these protocols and methods. Can anyone give me some pointers URLs? 回答1: Your best reference is always going to be the Python Online Documentation, specifically the section on

问题 I am trying to figure an agreement protocol on an unreliable channel. Basically two parties (A and B) have to agree to do something, so it's the two generals' problem. Since there is no bullet-proof solution, I am trying to do this. A continuously sends a message with sequence 1 When B receives seq 1 it continuously replies with sequence 2 At this point A receives seq 2 so it starts sending seq 3 ... My question. When can the two parties conclude that they can take the action ? Obviously I

问题 There is an interesting problem at hand. I have a role-playing MMOG running through a client application (not a browser) which sends the actions of my player to a server which keeps all the players in sync by sending packets back. Now, the game uses a top layer protocol over TCP/IP to send the data. However, wireshark does not know what protocol is being used and shows everything beyond the TCP header as a dump. Further, this dump does not have any plain text strings. Although the game has a

问题 I had code that was working in XCode 6 beta but stopped working recently after updating to xcode 6.1. This is my protocol: protocol CanDeserialiseFromJson { class func FromJson(json : JSONValue) -> Self } This is implementation: extension Invoice : CanDeserialiseFromJson { class func FromJson(json : JSONValue) -> Self { return Invoice() } } This fails giving error: 'Invoice' is not convertable to 'Self' As I said, this used to work and I can't work out why it doesn't anymore 回答1: Self in a