Question

通常使用MSMessage对象设置，我将使用MSMessageTemplateLayout作为发送MSMessage对象的基本设置。在iMessage API中，有一段有趣的代码，允许交互式MSMessage称为MSMessageLiveLayout，使用户无需完全打开MSMessage对象即可与MSMessage对象进行交互。

对于一个演示，我试图创建一个简单的计数器。对于MSMessage对象，我知道正确保存值更改的唯一方法是通过URL方案。

问题是我不确定如何正确更新当前的MSMessage URL以匹配新更改的值。另外，我将如何更新MSMessage对象的接收者端UI /数据以匹配发送者的变化？

每次按计数器按钮时，我试图通过使用新的URL值更新当前的activeConversation URL来访问当前的MSMessage URL。打印语句显示URL更新。但是，当我上下滚动MSMessage对象时，将调用willBecomeActive函数-放弃所有更改并继续使用旧的URL值。



class Demo: MSMessagesAppViewController {

var session: MSSession?
var count = 1
@IBOutlet var label: UILabel!

   func createURL() -> URL {
        var urlComponents = URLComponents()
        urlComponents.scheme = "https";
        urlComponents.host = "www.democounter.com";

        let item = URLQueryItem(name: "counter", value: "\(count)")
        urlComponents.queryItems?.append(item)

        return urlComponents.url!
    }


    func createMessage(_ url: URL) {

        if session == nil {
            session = MSSession()
        }

        let message = MSMessage(session: session!)

        let layout = MSMessageTemplateLayout()
        layout.caption = "Sending counter"
        let liveLayout = MSMessageLiveLayout(alternateLayout: layout)

        message.layout = liveLayout
        message.url = url


        let conversation = self.activeConversation

        conversation?.insert(message, completionHandler: {(error) in
            if let error = error {
                print(error)
            }
        })

        self.dismiss()
    }

// this is the blue box in the example attached that create and sends 
   the MSMessage object

    @IBAction func sendMessage(_ sender: UIButton) {
          let url = createURL()
          createMessage(url)
    }

// counter button, this is where I try to update the current MSMessage URL

    @IBAction func PressMe(_ sender: UIButton) {

        count += 1
        print(count)
        label.text = String(count)

        let conversation = self.activeConversation
        print(conversation?.selectedMessage?.url)

      // It prints the changes, but does not save the updated url to 
      the current MSMessage Object

        conversation?.selectedMessage?.url = createURL()
        print(conversation?.selectedMessage?.url)

    }

    func decodeURL(_ url: URL) {

        let components = URLComponents(url: url,
                                       resolvingAgainstBaseURL: false)

        for (index, queryItem) in (components?.queryItems?.enumerated())! {

            if queryItem.name == "counter"  {
                count = Int(queryItem.value!)!
            }
        }
    }

    override func willBecomeActive(with conversation: MSConversation) {
        if let messageURL = conversation.selectedMessage?.url {
            decodeURL(messageURL)
            caption = "It's your turn to counter"
            session = conversation.selectedMessage?.session
        }
        label.text = String(count)   
    }
}

[消息对象示例]（https://imgur.com/MVQipca）

使用MSMessageLiveLayout时如何更新MSMessage URL？

0 个答案: