mqtt拓展支持获取设备端的在线状态吗？这里仅仅提供一个思路： 设备状态是设备的一项数据，这个也需要设备上报其状态数据给app端，类似网络的心跳包，定时上报状态数据，一定时间没取到数据就认为设备离线。

... typical example would be that sensor data should be sent regularly to an MQTT broker. With version 6.0 ( Marshmallow), Android introduced Doze mode to optimize battery life. This function gradually turns everything off (display, CPU, WiFi, etc.) when no app is being used. With the extension des...

需要解析的JSON 格式 接收的信息，通过JSON解析后 把WD 的参数24 解读出来 显示到文本上 代码如下： 注意：此代码块是右键导出的png，具有还原代码块的功能，无需手动一个个处理。 具体还原方法请参考：https:...

用户反馈，连接状态正常，在初始化中订阅一次，收不到数据事件触发。 每次点击订阅一次，就能收到。这个需要深入测试一下。

...个平台的测试，先学习这个：https://www.fun123.cn/reference/iot/MQTTGuide.html。 网址：https://iot.dfrobot.com.cn/ 自行注册并登录。 新建一个订阅主题。 代码差别主要在：地址、端口不同，且使用用户名、密码认证（这里仅仅是演...

网址：https://open.iot.10086.cn/ 注册，及实名验证。https://baijiahao.baidu.com/s?id ... 0&wfr=spider&for=pc 非常的详细，就是我想要的步骤。 https://blog.csdn.net/xiaolong11 ... e/details/144806792 这个更详细。

...ains characters encoded in a way that is not valid in UTF-8 (as @Klas Lindbäck stated in a comment) - that's what the sed error message is trying to say by invalid byte sequence. Most likely, your input file uses a single-byte 8-bit encoding such as ISO-8859-1, frequently used to encode "Western E...

...位大佬好 我刚开始学习 APP INVENTOR编程。 尝试写了一个与MQTT服务器通讯的小程序。 这个小程序在手机当前程序状态运行正常 手机切换到别的应用 也运行正常。 但是 当手机屏幕熄灭 ， 刚熄灭的时候 还能正常接收MQTT的信息 ...

... I recently started playing with MQTT http://mqtt.org for Android as a way of doing what you're asking for (i.e. not SMS but data driven, almost immediate message delivery, scalable, not polling, etc.) I have a blog post with background information on this ...

...pport near real time push notification? ) I recently started playing with MQTT http://mqtt.org for Android as a way of doing this sort of thing (i.e. push notification that is not SMS but data driven, almost immediate message delivery, not polling, etc.) I have a blog post with background informat...