无法符合 swift 中的 objective-c 协议

Question

我正在尝试实现很棒的库 JSQMessagesViewController，但我不断收到错误消息“'ModelMessage' 不符合协议 'JSQMessageData'”，即使我的 class从 NSObject 继承，我实现了所需的属性

协议如下：

@protocol JSQMessageData <NSObject>

@required
 - (NSString *)senderId;
 - (NSString *)senderDisplayName;
 - (NSDate *)date;
 - (BOOL)isMediaMessage;
 - (NSUInteger)messageHash;

 @optional
 - (NSString *)text;
 - (id<JSQMessageMediaData>)media;

@end

这是我的 class

import Foundation

class ModelMessage: Model, JSQMessageData {

/* Required */
var senderId: NSString
var senderDisplayName: NSString
var date: NSDate
var isMediaMessage: Bool
var messageHash: UInt
/**/

var text_: String

var id:String!
var conversationId: String!
var imageUrl: String?
var recipientId: String!
var recipientRead: Bool!

var avatar: NSData?


init(data: NSDictionary){

    super.init()

    /* Required */
    self.senderId = getStringFromJSON(data, key:"senderId")
    self.senderDisplayName = "Me"
    let dateString = getStringFromJSON(data, key: "timeStamp")
    let dateDouble = (dateString as NSString).doubleValue / 1000.0
    self.date = NSDate(timeIntervalSince1970: dateDouble)
    self.isMediaMessage = false
    /**/

    self.text_ = getStringFromJSON(data, key:"text")

    self.id = getStringFromJSON(data, key:"id")
    self.conversationId = getStringFromJSON(data, key:"conversationId")
    self.recipientId = getStringFromJSON(data, key:"recipientId")
    self.recipientRead = data["recipientRead"] as! Bool

}

}

继承自

import Foundation

class Model: NSObject
{

func getStringFromJSON(data: NSDictionary, key: String) -> String {

    if let info = data[key] as? String{
        return info
    }
    return ""

}

}

Answer 1

试试这个

import Foundation

class ModelMessage: NSObject , JSQMessageData {

/* Required */
var senderId: NSString
var senderDisplayName: NSString
var date: NSDate
var isMediaMessage: Bool
var messageHash: UInt
/**/

var text_: String

var id:String!
var conversationId: String!
var imageUrl: String?
var recipientId: String!
var recipientRead: Bool!

var avatar: NSData?


init(data: NSDictionary){

    super.init()

    /* Required */
    self.senderId = getStringFromJSON(data, key:"senderId")
    self.senderDisplayName = "Me"
    let dateString = getStringFromJSON(data, key: "timeStamp")
    let dateDouble = (dateString as NSString).doubleValue / 1000.0
    self.date = NSDate(timeIntervalSince1970: dateDouble)
    self.isMediaMessage = false
    /**/

    self.text_ = getStringFromJSON(data, key:"text")

    self.id = getStringFromJSON(data, key:"id")
    self.conversationId = getStringFromJSON(data, key:"conversationId")
    self.recipientId = getStringFromJSON(data, key:"recipientId")
    self.recipientRead = data["recipientRead"] as! Bool

}

func getStringFromJSON(data: NSDictionary, key: String) -> String {

    if let info = data[key] as? String{
        return info
    }
    return ""

}


}

Answer 2

在实现没有可空性注释的 ObjC 协议时，尝试使用隐式解包选项。您也可以而且应该始终使用 String 而不是 NSString.

var senderId: String!
var senderDisplayName: String!
var date: NSDate!
var isMediaMessage: Bool
var messageHash: UInt

用 @objc 注释整个 class and/or 属性也有帮助。

如果仍然不起作用，请检查构建日志，因为它会告诉您缺少或未正确实现的协议功能。

无法符合 swift 中的 objective-c 协议

Cannot conform to objective-c protocol in swift

protocols

objective-c

ios

swift