Introduction In the world of the Internet of Things (IoT), the communication method is the “soul dialogue” between devices. The choice of which “language” you use often directly determines whether they work in harmony or talk past each other. IoT communication can actually be viewed from two levels:Physical Layer and Application Layer. The previous section … Read more
MQTT (Message Queuing Telemetry Transport) is a client-server messaging protocol based on the publish/subscribe model. After establishing an MQTT connection, whether the client publishes messages to the server or the server pushes messages related to subscribed topics to the client, messages are sent using the Publish packet. __Parameters__ QoS: Quality of Service (QoS): QoS 0 … Read more
When writing C++ projects with Qt, many people’s first reaction is to directly use Qt Creator to create a <span>.pro</span> project, compile, and run, which goes smoothly. However, once the project needs to interface with an existing CMake build system or needs to be built in a cross-platform CI environment, the <span>.pro</span> file becomes inflexible, … Read more
1. System Architecture Design 1. Architecture Flowchart 2. Class Diagram Design 2. Core Code Implementation 1. Chart Component Interface (IComponent) // ichartcomponent.h #ifndef ICHARTCOMPONENT_H #define ICHARTCOMPONENT_H #include<QWidget> #include<QVariantMap> #include<QPaintEvent> class IComponent : public QWidget { Q_OBJECT public: explicit IComponent(QWidget* parent = nullptr) : QWidget(parent) {} virtual ~IComponent() = default; // Basic property settings virtual void … Read more
With the development of smart vehicles, the functional scenarios and data volume of vehicle-cloud communication are gradually increasing. The MQTT protocol, characterized by its lightweight and reliability, has become a choice for many OEM vehicle-cloud communication protocols. This article mainly introduces the design of vehicle-cloud communication based on the MQTT protocol. What is MQTT? MQTT … Read more
In today’s rapidly advancing technological era, the Internet of Things (IoT) has become the core link connecting the physical world with the digital world. The MQTT communication protocol, as the “invisible bridge” in the IoT field, is playing an irreplaceable role in automation, cutting-edge AI technologies, industrial intelligent manufacturing, and smart warehousing due to its … Read more
When developing C++ desktop applications, the choice of GUI framework almost determines the development experience and subsequent maintenance costs of the project. For the past decade, Qt and wxWidgets have been mainstream, but in recent years, lightweight and modern solutions have begun to enter the developers’ field of vision, such as Dear ImGui and Elements. … Read more
MQTT is an application layer protocol. After the client and server establish a network connection (usually TCP/IP), the client sends a CONNECT message to the server to request the establishment of an MQTT connection, and the server replies with a CONNACK message to accept or reject the connection. The connection process is as follows: __CONNECT … Read more
Qt is increasingly used in the development of embedded systems, especially when high performance, aesthetic appeal, and strong interactivity in user interfaces (UI) are required. It is an ideal choice as it not only provides a powerful development framework but also offers developers a complete toolchain and ecosystem to help quickly build various smart devices.Reasons … Read more
In the MQTT protocol, Ping is a mechanism used to maintain the activity of the connection between the client and the server. It is implemented through two control messages: PINGREQ (heartbeat request) and PINGRESP (heartbeat response), ensuring that both parties are aware that the connection is still valid, especially in cases of prolonged inactivity. 1. … Read more