protocols

问题 I have two options when implementing protocol conformance in Swift, with the same end result: Implement the protocol within the class - that is, state the conformance at the top of class definition, and put implementation inside the class body, or Implement the protocol in an extension - that is, code up protocol conformance entirely outside the class. Here is an example: public class MyClass : CustomDebugStringConvertible { ... // Something public var debugDescription : String { return

问题 Are there any protocols, systems, etc. experimental or otherwise designed for allowing normal (as normal as can be) network operations (E-mail, DNS, HTML, etc.) over very high latency links? I'm thinking of minutes to an hour, or maybe two. Think light speed lag at a solar system scale. As a side note: research or speculation on the social effects hour to day scale communication delays would be interesting. Current trends tend towards delays of seconds to minutes (plus however long it takes

问题 So I created this method: - (void)addToViewController:(SecViewController *)controller didFinishEnteringItem:(NSString *)item;` <br> And Xcode keeps giving me Expected a type error at SecViewController * . What does that mean? SecViewController is not a type? 回答1: You have to declare SecViewController : @class SecViewController; ... at the top of your header. Note: Don't just #import all used headers. This just worsens your header dependencies. 来源： https://stackoverflow.com/questions/10427410

问题 I can see that stateful protocols lead to less botched together 'emulated state' like cookies. but testing becomes a lot harder to ensure that your implementation is correct and reconnects, and session continuations can be very hard to handle. Is it considered better practice to always use stateless protocols, or is it really domain specific? I think that authentication becomes easier when dealing with stateful protocols, but are there any other reasons you should use a stateful protocol? 回答1

问题 Closed . This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed last year . I need to write a simple file transfer protocol in C++ to upload or download a file from a client to a server. Right now both my client and server applications are do-it-all scripts. I want to modularize everything in classes/methods so I can more easily modify things later. To

问题 So I was playing around with protocol extensions and i ran into an "interesting" problem. I wanted to write a Meters and Kilometers units type for testing some things out. Its VERY easy to do this as a class where there is a base class and both sub classes override the base, while just overriding a simple value //Conversion factor between types enum DISTANCE_UNIT_TYPE : Double { case METER = 1.0; case KILOMETER = 0.001; } protocol DistanceUnit { var unitType : DISTANCE_UNIT_TYPE {get} var

问题 I would like to have a protocol that looks something like this: protocol ReturnType { var returnType: ImmutableMappable.Type { get } } The part of the enum implementing the protocol: extension ShimEndPoint: ReturnType { var returnType: ImmutableMappable.Type { switch self { case .deAuthorize(_, _): return EmptyResponse.self case .authorize(_, _): return AuthorizeResponse.self case .step(_, _, _, _): return StepResponse.self } } } EmptyResponse, AuthorizeResponse and StepResponse all implement

问题 How to use delegate methods of singleton/shared class? There is one singleton class having some protocol defined but I'm not getting how to access the delegate functions in other classes. Code snippet for a reference (swift): protocol AClassDelegate { func method1() } class A { static let shared = A() override init() { //initialisation of member variables } var delegate: AClassDelegate func foo() { } } class B: AClassDelegate { func bar() { // Note: not getting call to 'foo' method of class

问题 Here is my code what I would like to refactor: let myCell = MyCustomTableViewCell() self.createCell(myCell, reuseIdentifierString: "myCellIdentifier") the MyCustomTableViewCell conforms to the SetCell protocol so it works fine. and the SetCell protocol is not an @obj_c protocol. This is a swift protocol private func createCell<T where T:SetCell>(classType: T, reuseIdentifierString: String) -> UITableViewCell { var cell = _tableView.dequeueReusableCellWithIdentifier(reuseIdentifierString) as T

问题 I am about to write a message protocol going over a TCP stream. The receiver needs to know where the message boundaries are. I can either send 1) fixed length messages, 2) size fields so the receiver knows how big the message is, or 3) a unique message terminator (I guess this can't be used anywhere else in the message). I won't use #1 for efficiency reasons. I like #2 but is it possible for the stream to get out of sync? I don't like idea #3 because it means receiver can't know the size of