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cmake_minimum_required(VERSION 3.16)

project(tt_client VERSION 0.1 LANGUAGES CXX)

set(CMAKE_AUTOUIC ON)
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTORCC ON)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

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    QString str("807F");
    bool ok;
    short value = static_cast<short>(str.toUShort(&ok, 16));
    qDebug() << value;

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QOpenGLWidget
比如我们想要显示一张 QImage
我们可以用 QLabel 直接 setPixmap
也可以用 QGraphicsView 里设置一个 QGraphicsPixmapItem
但假如我们这张图需要不停刷新（30fps）并能随着控件大小缩放时
特别是 4K 分辨率下，性能 就出现了瓶颈
究其原因，还是 CPU 渲染慢，所以我们改用 GPU 来渲染
自然，我们首先想到的是 QOpenGLWidget
下面是个保持图像 400x640 比例的类，m_x、m_y 代表横纵黑边的长度
glwidget.h

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//worker.h
#pragma once

#include <QObject>

class Worker : public QObject
{
    Q_OBJECT
public:
    explicit Worker(QObject *parent = nullptr);

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#!/bin/bash
set -e
echo "Installing OpenCV 4.5.2 on your Raspberry Pi 64-bit OS"
echo "It will take minimal 1.5 hour !"
cd ~
# install the dependencies
sudo apt-get install -y build-essential cmake git unzip pkg-config
sudo apt-get install -y libjpeg-dev libtiff-dev libpng-dev
sudo apt-get install -y libavcodec-dev libavformat-dev libswscale-dev
sudo apt-get install -y libgtk2.0-dev libcanberra-gtk* libgtk-3-dev

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单例模式
很多人洋洋洒洒写了一大堆

比如这里 http://xtuer.github.io/qtbook-singleton/

比如这里 http://m.blog.csdn.net/Fei_Liu/article/details/69218935

但是Qt本身就提供了专门的宏 Q_GLOBAL_STATIC

通过这个宏不但定义简单，还可以获得线程安全性。

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QHeaderView::section{
background-color: qlineargradient(x1:0, y1:0, x2:0, y2:1,stop:0 #616161, stop: 0.5 #505050, stop: 0.6 #434343, stop:1 #656565);
color: white;
padding-left: 4px;
border: 1px solid #6c6c6c;
}
QTableView{
gridline-color: white;
}

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QSlider::groove:horizontal{
height:8px;
background-color:#646466;
border-radius:4px;
}
QSlider::groove:horizontal:disabled{
background-color:#3c3d3e;
}
QSlider::handle:horizontal{
background-color:#878787;

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*{
	outline: 0px;
}

QListWidget{
	color: white;
}

QListWidget::item:selected{
	background:#484c58;

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#include <iostream>
#include <cstdint>
int main() {
    uint8_t data[4] = {0xAA, 0xBB, 0xCC, 0xDD};
    float result = 0.0f;
    for (int i = 0; i < 4; ++i) {
        result += static_cast<float>(data[i]) * (1 << (8 * i));
    }
    std::cout << "Result: " << result << std::endl;
    return 0;