目录

需要注意的：

这是记录能用代码的，想知道原理的话，可以自行搜索

二话不说，上代码，拷了就能用

package com.doshare.boardroom.control.comm.mqtt

import android.content.Context
import android.util.Log
import androidx.lifecycle.ViewModelProvider
import com.doshare.boardroom.control.comm.retrofit.BoardRoomControlServiceImpl
import com.doshare.boardroom.control.common.device.AppHelper
import com.doshare.boardroom.control.common.device.DeviceIdUtils
import com.doshare.boardroom.control.view.viewmodel.HomeViewModel
import com.google.gson.Gson
import com.google.gson.internal.LinkedTreeMap
import org.eclipse.paho.android.service.MqttAndroidClient
import org.eclipse.paho.client.mqttv3.*


object MqttClient {
    private lateinit var mqttClient: MqttAndroidClient
    // TAG
    private val TAG = "AndroidMqttClient"

    /**
     * 创建连接
     */
    fun connect(context: Context) {
        val serverURI = "tcp://172.17.**.202:1883" //mqtt的服务器地址
        val username = "ds-mqtt"  //用户名
        val password = "do***321"  //密码

        mqttClient = MqttAndroidClient(context, serverURI, "IScreen-"+ DeviceIdUtils.getDeviceId(context))
        mqttClient.setCallback(object : MqttCallback {
            override fun messageArrived(topic: String?, message: MqttMessage?) {
            //这里是对收到mqtt消息进行处理的地方，

                Log.d(TAG, "Receive message: ${message.toString()} from topic: $topic")
                val messageMap = Gson().fromJson(message.toString(),Map::class.java)as                 LinkedTreeMap<String, Any>

            }

            override fun connectionLost(cause: Throwable?) {
                Log.d(TAG, "Connection lost ${cause.toString()}")
            }

            override fun deliveryComplete(token: IMqttDeliveryToken?) {

            }
        })

        // MQTT的连接设置
        val options = MqttConnectOptions()
        options.userName = username
        options.password = password.toCharArray()

        try {
            mqttClient.connect(options, null, object : IMqttActionListener {
                override fun onSuccess(asyncActionToken: IMqttToken?) {
                    Log.d(TAG, "Connection success")
                    subscribe("sunblind/user/+/notify") //订阅主题
                    
                }
                override fun onFailure(asyncActionToken: IMqttToken?, exception: Throwable?) {
                    Log.d(TAG, "Connection failure")
                }
            })
        } catch (e: MqttException) {
            e.printStackTrace()
        }

    }

    /**
     * 订阅主题
     */
    fun subscribe(topic: String, qos: Int = 1) {
        try {
            mqttClient.subscribe(topic, qos, null, object : IMqttActionListener {
                override fun onSuccess(asyncActionToken: IMqttToken?) {
                    Log.d(TAG, "Subscribed to $topic")
                }

                override fun onFailure(asyncActionToken: IMqttToken?, exception: Throwable?) {
                    Log.d(TAG, "Failed to subscribe $topic")
                }
            })
        } catch (e: MqttException) {
            e.printStackTrace()
        }
    }

    /**
     * 取消订阅
     */
    fun unsubscribe(topic: String) {
        try {
            mqttClient.unsubscribe(topic, null, object : IMqttActionListener {
                override fun onSuccess(asyncActionToken: IMqttToken?) {
                    Log.d(TAG, "Unsubscribed to $topic")
                }

                override fun onFailure(asyncActionToken: IMqttToken?, exception: Throwable?) {
                    Log.d(TAG, "Failed to unsubscribe $topic")
                }
            })
        } catch (e: MqttException) {
            e.printStackTrace()
        }
    }

    /**
     * 发布消息
     */
    fun publish(topic: String, msg: String, qos: Int = 1, retained: Boolean = false)  {
        try {
            val message = MqttMessage()
            message.payload = msg.toByteArray()
            message.qos = qos
            message.isRetained = retained
            mqttClient.publish(topic, message, null, object : IMqttActionListener {
                override fun onSuccess(asyncActionToken: IMqttToken?) {
                    Log.d(TAG, "$msg published to $topic")
                }

                override fun onFailure(asyncActionToken: IMqttToken?, exception: Throwable?) {
                    Log.d(TAG, "Failed to publish $msg to $topic")
                }
            })
        } catch (e: Exception) {
            e.printStackTrace()
        }
    }

    /**
     * 取消连接
     */
    fun disconnect() {
        try {
            mqttClient.disconnect(null, object : IMqttActionListener {
                override fun onSuccess(asyncActionToken: IMqttToken?) {
                    Log.d(TAG, "Disconnected")
                }

                override fun onFailure(asyncActionToken: IMqttToken?, exception: Throwable?) {
                    Log.d(TAG, "Failed to disconnect")
                }
            })
        } catch (e: MqttException) {
            e.printStackTrace()
        }
    }
}

需要注意的：

1.connect方法中serverURI //mqtt的服务器地址，username  //用户名，password  //密码这三个数据换成自己的
2.  mqttClient.connect中订阅的主题换成自己的

3.上面import了好多的无用包，直接删掉

4.改包名