PROSAGA码农传奇-C/C++-如何使用QComboBox选择如何保存QImage的格式

<div class =“post-text”itemprop =“text”>
  <P>
    如果ComboBox自动采用Qt可用于保存图像的格式，则可以改进应用程序
     <code>
      QImageWriter::supportedImageFormats()
    </code>
    。
  </p>
  <P>
    在下面的示例中，我展示了获取QComboBox的currentText的泛型方法：
  </p>
   <pre>
    <code>
      #include <QtWidgets>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QGraphicsScene *scene = new QGraphicsScene;
    QGraphicsView *view = new QGraphicsView{scene};
    scene->addRect(QRectF(0, 0, 100, 100), QPen(Qt::red), QBrush(Qt::blue));
    scene->addEllipse(QRectF(40, 30, 100, 100), QPen(Qt::green), QBrush(Qt::gray));
    QComboBox *combo_formats = new QComboBox;
    for(const QByteArray & format : QImageWriter::supportedImageFormats()){
        combo_formats->addItem(format);
    }
    QPushButton *save_button = new QPushButton{"Save"};
    QObject::connect(save_button, &QPushButton::clicked,[view, combo_formats](){
       QPixmap pixmap = view->grab();
       QString filename = QString("%1.%2").arg("image").arg(combo_formats->currentText());
       pixmap.save(filename);
    });
    QMainWindow w;
    QWidget *central_widget = new QWidget;
    w.setCentralWidget(central_widget);
    QFormLayout *lay = new QFormLayout{central_widget};
    lay->addRow(view);
    lay->addRow("Select Format:", combo_formats);
    lay->addRow(save_button);
    w.show();
    return a.exec();
}

</code>
  </pre>
  <P>
    在你的情况下：
  </p>
   <pre>
    <code>
      // constructor

for(const QByteArray & format : QImageWriter::supportedImageFormats()){
    ui->comboBoxFormat_A->addItem(format);
}
// ...

void MainWindow::bothPrintScreenBtn(const QString& pathImg, bool checkFolder)
{
    QString suffix = ui-comboBoxFormat_A->currentText();
    QString outA;
    do{
        outA = QString("%1/printScreenA/%2.%3").arg(pathImg).arg(counterA).arg(suffix);
        counterA++;
    }
    while((checkFolder && fileExists(outA)));
    QPixmap pixmapA = ui->graphicsViewLX->grab().toImage();
    pixmapA.save(outA);

QString outB;
    do{

outB = QString("%1/printScreenB/%2.%3").arg(pathImg).arg(counterB).arg(suffix);;
        counterB++;
    }
    while((checkFolder && fileExists(outB)));
    QPixmap pixmapB = ui->graphicsViewRX->grab()
    pixmapB.save(outB);
}

</code>
  </pre>
</DIV>