Cancel the default function of the qt form and the realization of the mouse dragging the form

1. Cancel the default functions of the qt form (zooming, minimizing, closing the window, dragging the form with the mouse, etc.)

setWindowFlags(Qt::FramelessWindowHint);

Second, realize clicking the mouse to drag the form

1. Add the following code to the *.h file

//头文件加入以下代码
#include <QMouseEvent>

//主体中加入以下代码
private:
    void mousePressEvent(QMouseEvent *event);
    void mouseMoveEvent(QMouseEvent *event);
    QPoint diff_pos;     //鼠标点击时相对窗体左上角的位移
    QPoint mouse_pos;    //鼠标点击时的位置
    QPoint window_pos;   //窗体左上角的位置

2. Add the following code to the *.cpp file

void 类名::mousePressEvent(QMouseEvent *event){
    
    
    mouse_pos=event->globalPos(); //获取鼠标点击时的绝对位置
    window_pos = this->pos();     //获取窗体的位置
    diff_pos=mouse_pos-window_pos;//计算相对位移
}

void 类名::mouseMoveEvent(QMouseEvent *event){
    
    
    QPoint pos = event->globalPos(); //获取鼠标移动后的绝对位置
    this->move(pos-diff_pos);        //设置窗体移动到的位置
}