QT QCustmPlot把折线图生成PDF

void MainWindow::on_actionSave_Document_triggered()

{

  QString fileName = QFileDialog::getSaveFileName(this, "Save document...", qApp->applicationDirPath(), "*.pdf");

  if (!fileName.isEmpty())

  {

    QPrinter printer;

    printer.setFullPage(true);

    printer.setPaperSize(QPrinter::A4);

    printer.setOrientation(QPrinter::Portrait);

    printer.setOutputFormat(QPrinter::PdfFormat);

    printer.setOutputFileName(fileName);

    ui->textEdit->document()->print(&printer);

  }

}