qt复制图片功能

右键弹出菜单栏，添加（给widget换色），删除（清除颜色），复制（复制widget图像到剪切板）

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QWidgetAction>
#include<QDebug>
#include <QMenu>
#include <QContextMenuEvent>
#include<QEvent>
#include <QRandomGenerator>
QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
    void copyWidgetTestImageToClipboard(QWidget* widgetTest);
    QString generateRandomHexColor();
public slots:
    void onAddActionTriggered();
    void onDeleteActionTriggered();
    void onCopyActionTriggered();
protected:
    void contextMenuEvent(QContextMenuEvent* event)override;
private:
    Ui::MainWindow *ui;
    QMenu* contextMenu; // 右键菜单
    QWidgetAction* addAction; // 新增菜单项
    QWidgetAction* deleteAction; // 删除菜单项
    QWidgetAction* copyAction;
};
#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <QClipboard>

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    // 创建右键菜单
    contextMenu = new QMenu(this);

    // 创建菜单项
    addAction = new QWidgetAction(contextMenu);
    addAction->setText(u8"新增");
    connect(addAction, &QAction::triggered, this, &MainWindow::onAddActionTriggered);
    contextMenu->addAction(addAction);

    deleteAction = new QWidgetAction(contextMenu);
    deleteAction->setText(u8"删除");
    connect(deleteAction, &QAction::triggered, this, &MainWindow::onDeleteActionTriggered);
    contextMenu->addAction(deleteAction);

    copyAction = new QWidgetAction(contextMenu);
    copyAction->setText(u8"复制");
    connect(copyAction, &QAction::triggered, this, &MainWindow::onCopyActionTriggered);
    contextMenu->addAction(copyAction);
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::copyWidgetTestImageToClipboard(QWidget *widgetTest)
{
    // 创建一个QPixmap对象，以便保存widgetTest中的图像
//    QPixmap pixmap(widgetTest->size());
//    widgetTest->render(&pixmap);
    QPixmap screenshot = widgetTest->grab();

    // 将图像复制到剪贴板中
    QClipboard* clipboard = QGuiApplication::clipboard();
    clipboard->setPixmap(screenshot);

}

QString MainWindow::generateRandomHexColor()
{
    // 生成3个[0, 255]之间的随机数作为RGB颜色值的分量
    int red = QRandomGenerator::global()->bounded(256);
    int green = QRandomGenerator::global()->bounded(256);
    int blue = QRandomGenerator::global()->bounded(256);

    // 将RGB颜色值转换为16进制字符串
    QString hexColor = QString("#%1%2%3")
        .arg(red, 2, 16, QChar('0'))
        .arg(green, 2, 16, QChar('0'))
        .arg(blue, 2, 16, QChar('0'));

    return hexColor;
}

void MainWindow::onAddActionTriggered()
{
    qDebug()<<"add";
    QString qss="background-color:"+generateRandomHexColor();
    ui->widgetTest->setStyleSheet(qss);
}

void MainWindow::onDeleteActionTriggered()
{
    qDebug()<<"delete";

    ui->widgetTest->setStyleSheet("background-color:transparent");
}

void MainWindow::onCopyActionTriggered()
{
    copyWidgetTestImageToClipboard(ui->widgetTest);
    qDebug()<<"copy";
}

void MainWindow::contextMenuEvent(QContextMenuEvent *event)
{
    if (ui->widgetTest->rect().contains(ui->widgetTest->mapFromGlobal(event->globalPos())))
    {
        contextMenu->exec(event->globalPos()); // 显示右键菜单
        event->accept();
    }
    else
    {
        QMainWindow::contextMenuEvent(event);
    }
}