qt 实现自定义小窗口可拖拽移动

初学C++，想实现小方块的点击和移动，直接给小方块的父元素 widget_7 绑定了事件监听，虽然实现了，却不理想。

#include <QMouseEvent>
#include "dragwin.h"

QPoint MediaServer::m_qMousePoint;
bool MediaServer::m_bIsMousePressed = false;
DragWin* MediaServer::curWidget;

MediaServer::MediaServer(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::MediaServer)
{
    ui->setupUi(this);
    ui->widget_7->installEventFilter(this); // 操作区
}

bool MediaServer::eventFilter(QObject *watched, QEvent *event) {
    QMouseEvent* pEvent = static_cast<QMouseEvent *>(event);    //将事件转换成鼠标事件,进行鼠标事件过滤
    switch (pEvent->type())
    {
    case QEvent::MouseButtonPress: //单击
        if(pEvent->button() == Qt::LeftButton)
        {
            m_bIsMousePressed = true;
            curWidget = qobject_cast<DragWin*>(watched);
            m_qMousePoint = pEvent->globalPos() - curWidget->pos();   //如果左键按下则记录当前鼠标在widget中位置
            qDebug() << "鼠标按下 pEvent->globalPos() ==== " << pEvent->globalPos();
            qDebug() << "鼠标按下 curWidget->pos() ==== " << curWidget->pos();
        }
        return true;
    case QEvent::MouseButtonRelease:
        if(pEvent->button() == Qt::LeftButton)
        {
            QList<DragWin*> labelList = ui->widget_7->findChildren<DragWin*>();
            for(int i = 0; i < labelList.size(); i++)
            {
                DragWin* label = labelList.at(i);
                label->setStyleSheet("background:#fff;border:1px solid #ccc;margin:0;");
            }
            curWidget = qobject_cast<DragWin*>(watched);
            curWidget->setStyleSheet("background:#fff;border:10px solid red;margin:0;");

            ui->winX->setText(QString::number(curWidget->pos().x()));
            ui->winY->setText(QString::number(curWidget->pos().y()));
            ui->winW->setText(QString::number(curWidget->rect().width()));
            ui->winH->setText(QString::number(curWidget->rect().height()));
            m_bIsMousePressed = false;
            qDebug() << "鼠标释放 pEvent->globalPos() ==== " << pEvent->globalPos();
        }
        return true;
    case QEvent::MouseMove:
        if(m_bIsMousePressed && (pEvent->buttons() == Qt::LeftButton))
        {
            qDebug() << "小窗口拖拽 event->type()==== " << event->type();
            curWidget = qobject_cast<DragWin*>(watched);
            int iL= pEvent->globalPos().x() - m_qMousePoint.x();
            int iT= pEvent->globalPos().y() - m_qMousePoint.y();
            iL <= 0 && (iL = 0);
            iT <= 0 && (iT = 0);
            curWidget->move(iL, iT);
            ui->winX->setText(QString::number(iL));
            ui->winY->setText(QString::number(iT));
            qDebug() << "鼠标拖拽 pEvent->globalPos() ==== " << pEvent->globalPos();
            qDebug() << "鼠标拖拽 m_qMousePoint ==== " << m_qMousePoint;
            return true;
        }
    default:
        break;
    }

    return QWidget::eventFilter(watched, event);
}

#ifndef MEDIASERVER_H
#define MEDIASERVER_H
#include <QWidget>
#include "dragwin.h"
using namespace neb;


QT_BEGIN_NAMESPACE
namespace Ui { class MediaServer; }
QT_END_NAMESPACE
class MediaServer : public QWidget
{
    Q_OBJECT
public:
    explicit MediaServer(QWidget *parent = nullptr);
    ~MediaServer();

protected:
    bool eventFilter(QObject *watched, QEvent *event) ;

public:
    static DragWin* curWidget;
    static QPoint       m_qMousePoint;		//记录当前位置
    static bool         m_bIsMousePressed;	//记录鼠标松放
private:
    Ui::MediaServer *ui;
    DragWin* newWidget = nullptr;
    QVector<DragWin*> winList;
};

#endif // MEDIASERVER_H

DragWin是方块类，后来把事件写到类里实现。可以看下大概思路

#include "dragwin.h"
#include "mediaserver.h"
#include <QDebug>
#include <QMouseEvent>

DragWin::DragWin(QWidget *parent) : PainterGragh(parent)
{
    this->setCursor(QCursor(Qt::DragLinkCursor));
}

int  DragWin::parseJSON(CJsonObject je) {
    je.Get("winId",winId);
    je.Get("winx", winX);
    je.Get("winy", winY);
    je.Get("winw", winW);
    je.Get("winh", winH);
    je.Get("winz", winZ);
    return 0;
}

void DragWin::mousePressEvent(QMouseEvent *event)//QMouseEvent *event
{
//    QMouseEvent* pEvent = static_cast<QMouseEvent *>(event);
     if(event->button()==Qt::LeftButton)
     {
         m_bIsMouseMove = false;
         MediaServer::m_bIsMousePressed = true;
//         m->curWidget = qobject_cast<QWidget*>(watched);
         MediaServer::curWidget = this;
         MediaServer::m_qMousePoint = event->globalPos() - MediaServer::curWidget->pos();   //如果左键按下则记录当前鼠标在widget中位置
     }
     else if(event->button()==Qt::RightButton)
     {
         qDebug()<<"RightButton clicked!！！！！！！！！！！！！！";
     }
}

void DragWin::mouseReleaseEvent(QMouseEvent *event)
{

    if(event->button()==Qt::LeftButton)
    {
        QString strX = QString::number(MediaServer::curWidget->pos().x());
        QString strY = QString::number(MediaServer::curWidget->pos().y());
        QString strW = QString::number(MediaServer::curWidget->rect().width());
        QString strH = QString::number(MediaServer::curWidget->rect().height());

        emit sendParamSignals(strX, strY, strW, strH);

//        winxEdit->setText(strX);
//        winyEdit->setText(strY);
//        winwEdit->setText(strW);
//        winhEdit->setText(strH);
        MediaServer::m_bIsMousePressed = false;
        qDebug() << "PainterGragh 鼠标释放 点击窗口 ==== " << event->globalPos() << " m_bIsMouseMove== " << m_bIsMouseMove << endl;

        if(m_bIsMouseMove) {
            QTcpClient  *tcp= QTcpClient::getInstance();
            int wid = MediaServer::curWidget->getId();
            qDebug() << "窗口移动位置 wid  ==== " << wid << endl;
            QString str1 = "{\"srxApi\":\"setWinRect\",\"param\":{\"wid\":"+ QString::number(wid) +",\"winx\":"+ strX +",\"winy\":"+ strY +",\"winw\":"+ strW +",\"winh\":"+ strH +"}}";
            tcp->sendJson(str1);
            qDebug() << "窗口移动位置 发送指令  ==== " << event->globalPos() << m_bIsMouseMove << endl;
        }
        m_bIsMouseMove = false;
    }
}


void DragWin::mouseMoveEvent(QMouseEvent *event)
{
    if(MediaServer::m_bIsMousePressed && (event->buttons() == Qt::LeftButton))
    {
        m_bIsMouseMove = true;
        //        qDebug() << "PainterGragh 小窗口拖拽 event->type()==== " << event->type() << this << endl;
        //        qDebug() << "PainterGragh 鼠标拖拽 pEvent->globalPos() ==== " << event->globalPos();
        //        qDebug() << "PainterGragh 鼠标拖拽 m_qMousePoint ==== " << MediaServer::m_qMousePoint;
        //        MediaServer::curWidget = qobject_cast<QWidget*>(watched);
        MediaServer::curWidget = this;
        int iL= event->globalPos().x() - MediaServer::m_qMousePoint.x();
        int iT= event->globalPos().y() - MediaServer::m_qMousePoint.y();
        iL <= 0 && (iL = 0);
        iT <= 0 && (iT = 0);
        MediaServer::curWidget->move(iL, iT);

        QString strW = QString::number(MediaServer::curWidget->rect().width());
        QString strH = QString::number(MediaServer::curWidget->rect().height());
        emit sendParamSignals(QString::number(iL), QString::number(iT), strW, strH);

//        winxEdit->setText(QString::number(iL));
//        winyEdit->setText(QString::number(iT));

    }
}

#ifndef DRAGWIN_H
#define DRAGWIN_H

#include <QWidget>
#include "paintergragh.h"
#include <QLineEdit>

#include <QMouseEvent>
#include <QPoint>
#include <QCursor>
#include <QRect>
#include "CJsonObject.hpp"
using namespace neb;

#define PADDING 2
class DragWin : public PainterGragh
{
    Q_OBJECT
public:
    explicit DragWin(QWidget *parent = nullptr);

public:
    int winId;
    int winZ;
    int winX;
    int winY;
    int winW;
    int winH;

    int getId(){return winId;}
    void setId(int val){
        winId = val;
    }
    int getWinZ(){return winZ;}
    void setWinZ(int val){
        winZ = val;
    }
    int parseJSON(CJsonObject je);
signals:

public slots:

private:
    bool m_bIsMouseMove = false;
    bool isLeftPressDown;
    QPoint dragPosition;
protected:
    void mousePressEvent(QMouseEvent *event);
    void mouseReleaseEvent(QMouseEvent *event);
    void mouseMoveEvent(QMouseEvent *event);
signals:
    void sendParamSignals(QString x, QString y, QString w, QString h);
public:
   //QLineEdit *winxEdit;
   //QLineEdit *winyEdit;
   //QLineEdit *winwEdit;
   //QLineEdit *winhEdit;
};

#endif // DRAGWIN_H

//新建几行几列
void MediaServer::on_new_btn_clicked()
{
    int line = ui->usrRow->text().toInt();
    int col = ui->usrLine->text().toInt();
    int winwVal = ui->winW->text().toInt();
    int winhVal = ui->winH->text().toInt();
    int winW = 100, winH = 100;

    if(winwVal && winhVal) {
        winW = winwVal;
        winH = winhVal;
    }
    for (int i=0;i<line;i++) {
        for (int j=0;j<col;j++) {
            DragWin *widget = new DragWin(ui->widget_7);

//            widget->winxEdit = ui->winX;//这个是指向PainterGragh
//            widget->winyEdit = ui->winY;
//            widget->winwEdit = ui->winW;
//            widget->winhEdit = ui->winH;

            widget->setGeometry(i*winW,j*winH,winW,winH);
            widget->setStyleSheet("background:#fff;border:1px solid #ccc;margin:0;");
            widget->show();
            curWidget = widget;
            qDebug() << "新建 curWidget==== " << curWidget << endl;

            connect(widget, &DragWin::sendParamSignals, this, &MediaServer::winParamSlot);

            QString strX = QString::number(curWidget->pos().x());
            QString strY = QString::number(curWidget->pos().y());
            QString strW = QString::number(winW);
            QString strH = QString::number(winH);
            ui->winX->setText(strX);
            ui->winY->setText(strY);
            ui->winW->setText(strW);
            ui->winH->setText(strH);
        }
    }
}

//新建窗口时 绑定槽函数，点击方块和拖拽时更新 x/y/w/h
void MediaServer::winParamSlot(QString strX, QString strY, QString strW, QString strH)
{
    ui->winX->setText(strX);
    ui->winY->setText(strY);
    ui->winW->setText(strW);
    ui->winH->setText(strH);
}