想问一下grabWindow()函数中WinId是什么意思,scaled怎么使用

QQfengxiangnan

#ifndef SCREENPRINT_H#define SCREENPRINT_H
#include <QWidget>#include <QTimer>#include <QMessageBox>#include <QPixmap>#include <QDesktopWidget>
namespace Ui {class ScreenPrint;}
class ScreenPrint : public QWidget{    Q_OBJECT    public:    explicit ScreenPrint(QWidget *parent = 0);    ~ScreenPrint();    private slots:    void on_newprintpushButton_clicked();    void  ShotScreenSlot();
private:    Ui::ScreenPrint *ui;    QTimer  * timer;    QPixmap   pixmap;
};
#endif // SCREENPRINT_H



void ScreenPrint::ShotScreenSlot(){    this->pixmap=QPixmap::grabWindow(QApplication::desktop()->winId());    ui->printlabel->setPixmap(pixmap.scaled(ui->printlabel->size()));
    this->show();    this->timer->stop();
}