C++ QDesktopWidget::winId方法代码示例

void ScreenSelector::grabColor()
{
    m_selectionRect = m_selectionRect.normalized();
    QDesktopWidget* desktop = QApplication::desktop();
    int screenNum = desktop->screenNumber(m_selectionRect.topLeft());
    QScreen* screen = QGuiApplication::screens()[screenNum];
    QPixmap screenGrab = screen->grabWindow(desktop->winId(),
        m_selectionRect.x(), m_selectionRect.y(), m_selectionRect.width(), m_selectionRect.height());
    QImage image = screenGrab.toImage();
    int numPixel = image.width() * image.height();
    int sumR = 0;
    int sumG = 0;
    int sumB = 0;

    for (int x = 0; x < image.width(); ++x) {
        for (int y = 0; y < image.height(); ++y) {
            QColor color = image.pixel(x, y);
            sumR += color.red();
            sumG += color.green();
            sumB += color.blue();
        }
    }

    QColor avgColor(sumR / numPixel, sumG / numPixel, sumB / numPixel);
    emit colorPicked(avgColor);
}

void Screenshot::dumpFullScreen()
{
        QDesktopWidget *desktop = QApplication::desktop();
        originalPixmap = QPixmap();
        originalPixmap = QPixmap::grabWindow(desktop->winId(), 0, 0,
                                             desktop->width(), desktop->height());
        currentPixmap = originalPixmap;
}

    QPixmap ScreenShooter::captureRect(const QRect &rect)
    {
#if (QT_VERSION >= QT_VERSION_CHECK(5, 0, 0))
        return QGuiApplication::primaryScreen()->grabWindow(0, rect.x(), rect.y(), rect.width(), rect.height());
#else
        QDesktopWidget *desktop = QApplication::desktop();

        return QPixmap::grabWindow(desktop->winId(), rect.x(), rect.y(), rect.width(), rect.height());
#endif
    }

QPixmap UBDesktopAnnotationController::getScreenPixmap()
{
    QDesktopWidget *desktop = QApplication::desktop();

    // we capture the screen in which the mouse is.
    const QRect primaryScreenRect = desktop->screenGeometry(QCursor::pos());
    QCoreApplication::flush();

    return QPixmap::grabWindow(desktop->winId(), primaryScreenRect.x()
                               , primaryScreenRect.y(), primaryScreenRect.width(), primaryScreenRect.height());
}

QPixmap CScreenShotView::createDesktopPixmap()
{
#ifdef Q_OS_MAC
    QPixmap pixmap = getScreenPixmap(m_desktopScreen);
#else
    QDesktopWidget *pDesktoWidget = QApplication::desktop();
    QPixmap pixmap = m_desktopScreen->grabWindow(pDesktoWidget->winId(),pDesktoWidget->geometry().x()
                                        ,pDesktoWidget->geometry().y(),pDesktoWidget->geometry().width(),pDesktoWidget->geometry().height());

#endif
    return pixmap;
}

  //----------------------------------------------------------------------------
  void GLWidget::captureScreen()
  {
    //LOG_ENTER_FUNC();

    QDesktopWidget *desktop = QApplication::desktop();
    _screenshot = QPixmap::grabWindow(
      desktop->winId(),
      0, 0,
      desktop->width(),
      desktop->height()
    );
  }

    QList<QPair<QPixmap, QRect> > ScreenShooter::captureWindows(const QList<WindowHandle> &windows)
    {
        QDesktopWidget *desktop = QApplication::desktop();
        QList< QPair<QPixmap, QRect> > result;

        for(const WindowHandle &window: windows)
        {
            if(!window.isValid())
                continue;

            const QRect &windowGeometry = window.rect();

#if (QT_VERSION >= QT_VERSION_CHECK(5, 0, 0))
            result.append(qMakePair(QGuiApplication::primaryScreen()->grabWindow(desktop->winId(), windowGeometry.x(), windowGeometry.y(), windowGeometry.width(), windowGeometry.height()), windowGeometry));
#else
            result.append(qMakePair(QPixmap::grabWindow(desktop->winId(), windowGeometry.x(), windowGeometry.y(), windowGeometry.width(), windowGeometry.height()), windowGeometry));
#endif
        }

        return result;
    }

int main(int argc, char** argv)
{
    QApplication app(argc, argv);
    QDesktopWidget *desktop = QApplication::desktop();
    float scale = dpiScaleFactor(desktop);
    qDebug() << "Scale factor" << scale;
    QPixmap screenshot = QPixmap::grabWindow(desktop->winId(),
        0, 0, desktop->width()*scale, desktop->height()*scale);
    QFile file("screenshot.png");
    file.open(QIODevice::WriteOnly);
    screenshot.save(&file, "JPEG", 100);//(-1..0-100) 0 smallest lowest quality
    return app.exec();
}

    QPixmap ScreenShooter::captureWindow(WindowHandle window)
    {
        if(!window.isValid())
            return QPixmap();

        const QRect &windowGeometry = window.rect();

#if (QT_VERSION >= QT_VERSION_CHECK(5, 0, 0))
        return QGuiApplication::primaryScreen()->grabWindow(0, windowGeometry.x(), windowGeometry.y(), windowGeometry.width(), windowGeometry.height());
#else
        QDesktopWidget *desktop = QApplication::desktop();

        return QPixmap::grabWindow(desktop->winId(), windowGeometry.x(), windowGeometry.y(), windowGeometry.width(), windowGeometry.height());
#endif
    }

    QPixmap ScreenShooter::captureScreen(int screenIndex)
    {
        QDesktopWidget *desktop = QApplication::desktop();

        if(screenIndex < 0 || screenIndex >= desktop->screenCount())
            return QPixmap();

        const QRect &screenGeometry = desktop->screenGeometry(screenIndex);

#if (QT_VERSION >= QT_VERSION_CHECK(5, 0, 0))
        return QGuiApplication::primaryScreen()->grabWindow(0, screenGeometry.x(), screenGeometry.y(), screenGeometry.width(), screenGeometry.height());
#else
        return QPixmap::grabWindow(desktop->winId(), screenGeometry.x(), screenGeometry.y(), screenGeometry.width(), screenGeometry.height());
#endif
    }

void MainWindow::on_screenShot()
{
    QPixmap pixmap;
    QDesktopWidget *desktop = QApplication::desktop();
    pixmap = QPixmap::grabWindow(desktop->winId(), pos().x(), pos().y(), frameGeometry().width(), frameGeometry().height());
    QString format = "png";
    QString initialPath = QDir::currentPath()+
                          tr("/untitled.") + format;

    QString fileName = QFileDialog::getSaveFileName(this,
                       tr("Save As"),initialPath,
                       tr("%1 Files (*.%2);;All Files (*)")
                       .arg(format.toUpper()).arg(format));
    if (!fileName.isEmpty())
        pixmap.save(fileName, format.toLatin1());
}

void AppView::makeScreenshot() {
    // Making screenshot
    QDesktopWidget* desktop = QApplication::desktop();
    QRect geo = desktop->screenGeometry(desktop->screenNumber(QCursor::pos()));

    screenshot_ = QGuiApplication::primaryScreen()->grabWindow(desktop->winId(),
                                                               geo.left(),
                                                               geo.top(),
                                                               geo.width(),
                                                               geo.height());

    int width = screenshot_.width(),
        height = screenshot_.height();

    setGeometry(0, 0, width, height);
    scene_.clear();
    scene_.setSceneRect(0, 0, width, height);
    reinitVisibleArea();

    // Background screenshot
    scene_.addPixmap(screenshot_);
    showFullScreen();
}

KSnapshot::KSnapshot(QWidget *parent,  KSnapshotObject::CaptureMode mode )
  : QDialog(parent), KSnapshotObject(), modified(true), savedPosition(QPoint(-1, -1))
{
    // TEMPORARY Make sure "untitled" enters the string freeze for 4.6, 
    // as explained in http://lists.kde.org/?l=kde-graphics-devel&m=128942871430175&w=2
    const QString untitled = QString(tr("untitled"));
    
    setWindowTitle(""); 
    grabber = new QWidget( 0,  Qt::X11BypassWindowManagerHint );
    
    // TODO X11 (Xinerama and Twinview, actually) and Windows use different coordinates for the two monitors case
    //
    // On Windows, there are two displays. The origin (0, 0) ('o') is the top left of display 1. If display 2 is to the left, then coordinates in display 2 are negative:
    //  .-------.
    //  |       |o-----. 
    //  |   2   |      |
    //  |       |   1  |
    //  ._______.._____.
    //
    // On Xinerama and Twinview, there is only one display and two screens. The origin (0, 0) ('o') is the top left of the display:
    //  o-------.
    //  |       |.-----. 
    //  |   2   |      |
    //  |       |   1  |
    //  ._______.._____.
    //
    // Instead of moving to (-10000, -10000), we should compute how many displays are and make sure we move to somewhere out of the total coordinates. 
    //   - Windows: use GetSystemMetrics ( http://msdn.microsoft.com/en-us/library/ms724385(v=vs.85).aspx )

    // If moving to a negative position, we need to count the size of the dialog; moving to a positive position avoids having to compute the size of the dialog

    grabber->move( -10000, -10000 ); // FIXME Read above

    grabber->installEventFilter( this );

    QVBoxLayout *vbox = new QVBoxLayout( this );
    setLayout(vbox);
    mainWidget = new KSnapshotWidget();
    vbox->addWidget(mainWidget);

    connect(mainWidget->ok_btn, SIGNAL(clicked()), SLOT(onOkBtnClicked()));
    connect(mainWidget->cancel_btn, SIGNAL(clicked()), SLOT(onCancelBtnClicked()));
    connect(mainWidget->save_btn, SIGNAL(clicked()), SLOT(onSaveBtnClicked()));
    connect(mainWidget->help_btn, SIGNAL(clicked()), SLOT(onHelpBtnClicked()));
    connect(mainWidget->lblImage, SIGNAL(startDrag()), SLOT(slotDragSnapshot()));
    connect(mainWidget->btnNew, SIGNAL(clicked()), SLOT(slotGrab()));
    connect(mainWidget->comboMode, SIGNAL(activated(int)), SLOT(slotModeChanged(int)));

    if (qApp->desktop()->numScreens() < 2) {
        mainWidget->comboMode->removeItem(CurrentScreen);
    }

    mainWidget->spinDelay->setSuffix(tr(" second", " seconds"));

    grabber->show();
    grabber->grabMouse();

#ifdef HAVE_X11_EXTENSIONS_XFIXES_H
    {
        int tmp1, tmp2;
        //Check whether the XFixes extension is available
        Display *dpy = QX11Info::display();
        if (!XFixesQueryExtension( dpy, &tmp1, &tmp2 )) {
            mainWidget->cbIncludePointer->hide();
            mainWidget->lblIncludePointer->hide();
        }
    }
#elif !defined(Q_WS_WIN)
    mainWidget->cbIncludePointer->hide();
    mainWidget->lblIncludePointer->hide();
#endif
    setMode(KSnapshotObject::Region);

    qDebug() << "Mode = " << mode;
    if ( mode == KSnapshotObject::FullScreen ) {
        snapshot = QPixmap::grabWindow( QApplication::desktop()->winId() );
#ifdef HAVE_X11_EXTENSIONS_XFIXES_H
        if ( haveXFixes && includePointer() )
            grabPointerImage(0, 0);
#endif
    }
    else if ( mode == KSnapshotObject::CurrentScreen ) {
        qDebug() << "Desktop Geom = " << QApplication::desktop()->geometry();
        QDesktopWidget *desktop = QApplication::desktop();
        int screenId = desktop->screenNumber( QCursor::pos() );
        qDebug() << "Screenid = " << screenId;
        QRect geom = desktop->screenGeometry( screenId );
        qDebug() << "Geometry = " << screenId;
        snapshot = QPixmap::grabWindow( desktop->winId(),
                geom.x(), geom.y(), geom.width(), geom.height() );
    }
    else {
        setMode( mode );
        switch(mode)
        {
            case KSnapshotObject::WindowUnderCursor:
                {
                    setIncludeDecorations( true );
                    performGrab();
                    break;
//.........这里部分代码省略.........

void KSnapshot::performGrab()
{
    int x = 0;
    int y = 0;

    grabber->releaseMouse();
    grabber->hide();
    grabTimer.stop();

    title.clear();
    windowClass.clear();

    if ( mode() == ChildWindow ) {
        WindowGrabber wndGrab;
        connect( &wndGrab, SIGNAL(windowGrabbed(QPixmap)),
                           SLOT(slotWindowGrabbed(QPixmap)) );
        wndGrab.exec();
        QPoint offset = wndGrab.lastWindowPosition();
        x = offset.x();
        y = offset.y();
        qDebug() << "last window position is" << offset;
    }
    else if ( mode() == WindowUnderCursor ) {
        snapshot = WindowGrabber::grabCurrent( includeDecorations() );

        QPoint offset = WindowGrabber::lastWindowPosition();
        x = offset.x();
        y = offset.y();

        // If we're showing decorations anyway then we'll add the title and window
        // class to the output image meta data.
        if ( includeDecorations() ) {
            title = WindowGrabber::lastWindowTitle();
        }
    }
    else if ( mode() == CurrentScreen ) {
        qDebug() << "Desktop Geom2 = " << QApplication::desktop()->geometry();
        QDesktopWidget *desktop = QApplication::desktop();
        int screenId = desktop->screenNumber( QCursor::pos() );
        qDebug() << "Screenid2 = " << screenId;
        QRect geom = desktop->screenGeometry( screenId );
        qDebug() << "Geometry2 = " << geom;
        x = geom.x();
        y = geom.y();
        snapshot = QPixmap::grabWindow( desktop->winId(),
                x, y, geom.width(), geom.height() );
    }
    else {
        snapshot = QPixmap::grabWindow( QApplication::desktop()->winId() );
    }
#ifdef HAVE_X11_EXTENSIONS_XFIXES_H
    if (haveXFixes && includePointer()) {
        grabPointerImage(x, y);
    }
#endif // HAVE_X11_EXTENSIONS_XFIXES_H

    if ( snapshot.isNull() )
    {
        mainWidget->ok_btn->setEnabled(false);
        mainWidget->save_btn->setEnabled(false);
    }
    else
    {
        mainWidget->ok_btn->setEnabled(true);
        mainWidget->save_btn->setEnabled(true);
    }

    updatePreview();
    QApplication::restoreOverrideCursor();
    modified = true;
    updateCaption();
    if (savedPosition != QPoint(-1, -1)) {
        move(savedPosition);
    }
    show();
}

QColor Overlay::grabScreenColor(const QPoint &p)
{
    QDesktopWidget *desktop = QApplication::desktop();
    QPixmap pixmap = QGuiApplication::screens().at(desktop->screenNumber())->grabWindow(desktop->winId(), p.x(), p.y(), 1, 1);
    QImage i = pixmap.toImage();
    return i.pixel(0, 0);
}