Android集成MQTT做一个客户端
16lz
2021-01-23
前言
基于IDEA做的Android的MQTT客户端开发,没有运用太多android技术,纯净版开发。不做过多MQTT的介绍及服务器的配置,直接上代码。
编译开始
第一步,新建一个Android项目,在项目目录下的build.gradle中的repositories添加如下设置:
maven { url "https://repo.eclipse.org/content/repositories/paho-releases/" }
第二步,app目录下的build.gradle中的dependencies引入:
implementation 'org.eclipse.paho:org.eclipse.paho.client.mqttv3:1.1.1'
第三步,在AndroidManifest中的manifest标签加入如下权限:
第四步,代码实现:
为了方便测试我写了一个MQTT实体类,目的是默认填写一个服务器连接。需要写新的连接可以new对象。
/** * MQTT连接实体类,作用是自定义配置连接信息,以实现默认链接 * 构造方法一定要写! * @author Peng */public class MQTTentity { //以下请自己配置否则MainActivity中button_login的监听会有问题 private String host; private String userName; private String passWord; private String timeTopic; public String getHost() { return host; } public void setHost(String host) { this.host = host; } public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public String getPassWord() { return passWord; } public void setPassWord(String passWord) { this.passWord = passWord; } public String getTimeTopic() { return timeTopic; } public void setTimeTopic(String timeTopic) { this.timeTopic = timeTopic; } public MQTTentity() { } public MQTTentity(String host, String userName, String passWord, String timeTopic) { this.host = host; this.userName = userName; this.passWord = passWord; this.timeTopic = timeTopic; } @Override public String toString() { return "MQTTentity{" + "host='" + host + '\'' + ", userName='" + userName + '\'' + ", passWord='" + passWord + '\'' + ", timeTopic='" + timeTopic + '\'' + '}'; }}
然后在MainActivity中先声明MQTT实体和相关配置类:
//我们自己新建的MQTT实体类 private MQTTentity mqttentity; private MqttClient client; private MqttConnectOptions options; //以下两个声明目的是为了实现MQTT消息在testview刷新 private ScheduledExecutorService scheduler; private Handler handler;
同时别忘了声明自己定义的button、textview、edittext等控件。
为了保证每个客户端在安装的时候不会冲突,在获取MQTT连接的时候不会出错,需要先写一个获取IMEI的方法,保证各个client唯一。
/** * 获取手机imei * @param context * @param slotId * @return */ public static String getIMEI(Context context, int slotId) { try { TelephonyManager manager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); Method method = manager.getClass().getMethod("getImei", int.class); String imei = (String) method.invoke(manager, slotId); return imei; } catch (Exception e) { return ""; } }
接下来对MQTT进行初始化,我编了一个init()方法:
/** * MQTT初始化连接 */ private void init(MQTTentity mqttentity) { try { String imei = getIMEI(MainActivity.this, 0); //host为主机名,test为clientid即连接MQTT的客户端ID,一般以客户端唯一标识符表示,MemoryPersistence设置clientid的保存形式,默认为以内存保存 client = new MqttClient(mqttentity.getHost(), imei, new MemoryPersistence()); //MQTT的连接设置 options = new MqttConnectOptions(); //设置是否清空session,这里如果设置为false表示服务器会保留客户端的连接记录,这里设置为true表示每次连接到服务器都以新的身份连接 options.setCleanSession(true); //设置连接的用户名 options.setUserName(mqttentity.getUserName()); //设置连接的密码 options.setPassword(mqttentity.getPassWord().toCharArray()); // 设置超时时间 单位为秒 options.setConnectionTimeout(10); // 设置会话心跳时间 单位为秒 服务器会每隔1.5*20秒的时间向客户端发送个消息判断客户端是否在线,但这个方法并没有重连的机制 options.setKeepAliveInterval(20); //设置回调 client.setCallback(new MqttCallback() { @Override public void connectionLost(Throwable cause) { //连接丢失后,一般在这里面进行重连 System.out.println("connectionLost----------"); } @Override public void deliveryComplete(IMqttDeliveryToken token) { //publish后会执行到这里 System.out.println("deliveryComplete---------" + token.isComplete()); } @Override public void messageArrived(String topicName, MqttMessage message) { //subscribe后得到的消息会执行到这里面 System.out.println("messageArrived----------"); Message msg = new Message(); msg.what = 1; //收到消息标志位 msg.obj = topicName + "_" + message.toString(); handler.sendMessage(msg); // hander 回传 } }); } catch (Exception e) { e.printStackTrace(); } }
初始化完成后就是建立连接并设置重连,以确保连接断开后自动重连:
/** * MQTT建立连接及重连 */ private void startReconnect() { scheduler = Executors.newSingleThreadScheduledExecutor(); scheduler.scheduleAtFixedRate(new Runnable() { @Override public void run() { if (!client.isConnected()) { connect(); } } }, 0, 10 * 1000, TimeUnit.MILLISECONDS); }
以上基本完成所有工作,先看下效果图:
下面贴上MainActivity,XML布局就不贴了,自己设置布局并给每个控件添加ID就好:
import android.content.Context;import android.os.Handler;import android.os.Message;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.telephony.TelephonyManager;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;import android.widget.Toast;import org.eclipse.paho.client.mqttv3.*;import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;import java.lang.reflect.Method;import java.util.concurrent.Executors;import java.util.concurrent.ScheduledExecutorService;import java.util.concurrent.TimeUnit;public class MainActivity extends AppCompatActivity { //服务器参数配置 private MQTTentity mqttentity; private MqttClient client; private MqttConnectOptions options; private ScheduledExecutorService scheduler; private Handler handler; private TextView textView; private EditText textView_intip; private EditText textView_intid; private EditText textView_intpwd; private EditText textView_inttopic; private EditText textView_send; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textView = findViewById(R.id.text_show); textView_intip = findViewById(R.id.textView_intip); textView_intid = findViewById(R.id.textView_intid); textView_intpwd = findViewById(R.id.textView_intpwd); textView_inttopic = findViewById(R.id.textView_inttopic); textView_send = findViewById(R.id.textView_send); Button button_defaultlogin = findViewById(R.id.button_defaultlogin); Button button_login = findViewById(R.id.button_login); Button button_publish = findViewById(R.id.button_publish); button_defaultlogin.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { mqttentity = new MQTTentity(); init(mqttentity); startReconnect(); } }); button_login.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String host = textView_intip.getText().toString(); String id = textView_intid.getText().toString(); String pwd = textView_intpwd.getText().toString(); String topic = textView_inttopic.getText().toString(); if (host.length() != 0 && id.length() != 0 && pwd .length() != 0 && topic .length() != 0){ mqttentity = new MQTTentity(host,id,pwd,topic); init(mqttentity); startReconnect(); }else { Toast.makeText(MainActivity.this, "请输入完整连接信息!", Toast.LENGTH_SHORT).show(); } } }); button_publish.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String send = textView_send.getText().toString(); if (mqttentity != null && send.length() != 0){ publish(mqttentity.getTimeTopic(),send); }else { Toast.makeText(MainActivity.this, "请检查连接或信息!", Toast.LENGTH_SHORT).show(); } } }); handler = new Handler(new Handler.Callback() { @Override public boolean handleMessage(Message msg) { if (msg.what == 1){ Toast.makeText(MainActivity.this, (String) msg.obj, Toast.LENGTH_SHORT).show(); textView.setText((String) msg.obj); }else if (msg.what == 2){ try { client.subscribe(mqttentity.getTimeTopic(), 1);//订阅主题“timeTopic” Toast.makeText(MainActivity.this, "连接成功", Toast.LENGTH_SHORT).show(); } catch (Exception e) { e.printStackTrace(); } }else if (msg.what == 3){ Toast.makeText(MainActivity.this, "连接失败,系统正在重连", Toast.LENGTH_SHORT).show(); } return false; } }); } /** * MQTT初始化连接 */ private void init(MQTTentity mqttentity) { try { String imei = getIMEI(MainActivity.this, 0); //host为主机名,test为clientid即连接MQTT的客户端ID,一般以客户端唯一标识符表示,MemoryPersistence设置clientid的保存形式,默认为以内存保存 client = new MqttClient(mqttentity.getHost(), imei, new MemoryPersistence()); //MQTT的连接设置 options = new MqttConnectOptions(); //设置是否清空session,这里如果设置为false表示服务器会保留客户端的连接记录,这里设置为true表示每次连接到服务器都以新的身份连接 options.setCleanSession(true); //设置连接的用户名 options.setUserName(mqttentity.getUserName()); //设置连接的密码 options.setPassword(mqttentity.getPassWord().toCharArray()); // 设置超时时间 单位为秒 options.setConnectionTimeout(10); // 设置会话心跳时间 单位为秒 服务器会每隔1.5*20秒的时间向客户端发送个消息判断客户端是否在线,但这个方法并没有重连的机制 options.setKeepAliveInterval(20); //设置回调 client.setCallback(new MqttCallback() { @Override public void connectionLost(Throwable cause) { //连接丢失后,一般在这里面进行重连 System.out.println("connectionLost----------"); } @Override public void deliveryComplete(IMqttDeliveryToken token) { //publish后会执行到这里 System.out.println("deliveryComplete---------" + token.isComplete()); } @Override public void messageArrived(String topicName, MqttMessage message) { //subscribe后得到的消息会执行到这里面 System.out.println("messageArrived----------"); Message msg = new Message(); msg.what = 1; //收到消息标志位 msg.obj = topicName + "_" + message.toString(); handler.sendMessage(msg); // hander 回传 } }); } catch (Exception e) { e.printStackTrace(); } } /** * 获取手机imei * @param context * @param slotId * @return */ public static String getIMEI(Context context, int slotId) { try { TelephonyManager manager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); Method method = manager.getClass().getMethod("getImei", int.class); String imei = (String) method.invoke(manager, slotId); return imei; } catch (Exception e) { return ""; } } /** * MQTT建立连接及重连 */ private void startReconnect() { scheduler = Executors.newSingleThreadScheduledExecutor(); scheduler.scheduleAtFixedRate(new Runnable() { @Override public void run() { if (!client.isConnected()) { connect(); } } }, 0, 10 * 1000, TimeUnit.MILLISECONDS); } /** * MQTT连接状态鉴别 */ private void connect() { new Thread(new Runnable() { @Override public void run() { try { client.connect(options); Message msg = new Message(); msg.what = 2; handler.sendMessage(msg); } catch (Exception e) { e.printStackTrace(); Message msg = new Message(); msg.what = 3; handler.sendMessage(msg); } } }).start(); } /** * 向Topic发送消息 * @param topic * @param sendMessage */ public void publish(String topic,String sendMessage){ Integer qos = 0; Boolean retained = false; try { if (client != null){ client.publish(topic, sendMessage.getBytes(), qos.intValue(), retained.booleanValue()); } } catch (MqttException e) { e.printStackTrace(); } } @Override protected void onDestroy() { super.onDestroy(); try { scheduler.shutdown(); client.disconnect(); } catch (MqttException e) { e.printStackTrace(); } }}
以上参考于博主asjqkkkk的Android开发之MQTT的使用。他使用的是绑定服务的方式,我不太会,做了修改直接在MainActivity中做的部署。
更多相关文章
- 网络对讲机C#服务器 Android客户端(三) android客户端代码分析
- android弹出选择对话框-仿某团购网android客户端栏目选择
- android应用市场、社区客户端、漫画App、TensorFlow Demo、歌词
- android 客户端与服务端的通信 发送get和post请求并获取数据
- Android设备上i-jetty环境的搭建-手机上的web服务器
- Android通过Http连接MySQL 实现登陆/注册(数据库+服务器+客户端)
- Android 消息机制:handler looper message
- android客户端和struts框架之间的通信