初始化在线成员 - Websocket在线状态

如果要监听一个成员的上下线事件或者能查询到一个channel上有哪些成员在线，必须要：

• 建立连接时，传入成员的id和data
• 客户端订阅一个channel时，增加presence参数，并且将enable设为true

前置条件

• js SDK 2.7+
• Android SDK 0.2.0+
• IOS SDK 0.2.0+

指定客户端id和data

要监听一个成员线状态，在建立连接时，需要传入成员的id和data，id和data数据将会出现在上下线事件对象中以及在线用户列表的查询结果，用于区分不同的成员。

id应为成员的唯一标识符，如果为空，GoEasy将会为每个客户端生成一个默认唯一标识。 data作为一个自定义对象，可以包含任意需要的属性，比如头像和昵称。

Javascript

    goeasy.connect({
        id: "成员唯一标识，如 user-001",
        data: {"avatar":"/www/xxx.png","nickname":"Neo"},//可扩展更多的成员信息，查询或监听成员上下线事件时，event对象将包含id和data
        onSuccess: function () {  //连接成功
            console.log("GoEasy connect successfully.") //连接成功
        },
        onFailed: function (error) { //连接失败
            console.log("Failed to connect GoEasy, code:"+error.code+ ",error:"+error.content);
        },
        onProgress:function(attempts) { //连接或自动重连中
            console.log("GoEasy is connecting", attempts);    
        }
    });

Android

    val connectOptions = ConnectOptions()
    connectOptions.id = "user-001" // 成员唯一标识
    connectOptions.data = mapOf("nickname" to "Neo", "avatarId" to "/www/xxx.png") //可扩展更多的成员信息，查询或监听成员上下线事件时，event对象将包含id和data
    
    val connectEventListener = object : ConnectEventListener() {
        override fun onSuccess(data: GResult<*>) {
            unshiftMessage("Connect to GoEasy success.")
        }
        override fun onFailed(error: GResult<*>) {
            unshiftMessage("Connect to GoEasy failed: code: ${error.code} data: ${error.data}")
        }
        override fun onProgress(attempts: Int) {
            unshiftMessage("尝试重连次数:$attempts")
        }
    }
    
    GoEasy.connect(connectOptions, connectEventListener)

iOS

    let connectOptions = ConnectOptions(
        id: "user-001", // 成员唯一标识
        data: ["nickname": "Neo", "avatarId": "/www/xxx.png"]  //可扩展更多的成员信息，查询或监听成员上下线事件时，event对象将包含id和data
    )
    
    let connectEventListener = ConnectEventListener(
        onSuccess: { result in
            print("连接成功 result: \(result)")
        },
        onFailed: { result in
            print("连接失败 result: \(result)")
        },
        onProgress: { attempts in
            print("尝试重连次数: \(attempts)")
        }
    )
    
    GoEasy.connect(options: connectOptions, connectEventListener: connectEventListener)

设置channel的presence属性

订阅一个channel时，增加presence参数，并且将enable设为true，该订阅行为将会被监听。

Javascript

    goeasy.pubsub.subscribe({
        channel: "my_channel",//替换为您自己的channel
        presence: {
            enable: true
        }, 
        onMessage: function (message) {
            //收到消息
            console.log("Channel:" + message.channel + " content:" + message.content);
        },
        onSuccess: function () {
            console.log("Channel订阅成功。");
        },
        onFailed: function (error) {
            console.log("Channel订阅失败, 错误编码：" + error.code + " 错误信息：" + error.content)
        }
    });

Android

    val subscribeOptions = SubscribeOptions(
        channel = "my_channel",
        presence = mapOf("enable" to true),
        onMessage = { message: PubSubMessage ->
            /** PubSubMessage:
                channel: String
                content: String
                time: Long
            */
            Log.i("Channel","Message content: ${message.content}")
        },
        onSuccess = {
            Log.i("Channel","订阅成功")
        },
        onFailed = { error ->
            Log.i("Channel","订阅失败: code: ${error.code} data: ${error.data}")
        }
    )
    GPubSub.subscribe(subscribeOptions)

iOS

    var subscribeOptions = SubscribeOptions(
        channel: "my_channel",
        presence: ["enable": true],
        onMessage: { message in
            /** PubSubMessage:
                channel: String
                content: String
                time: Int64
            */
            print("onMessage:\(message.content)")
        },
        onSuccess:{
            print("订阅成功")
        },
        onFailed:{ result in
            print("订阅失败: code:\(result.code) data:\(result.data)")
        }
    )
    GPubSub.subscribe(options: subscribeOptions)