Двойное открытие QDialog

void MainWindow::on_currentFolder_doubleClicked(const QModelIndex &index)
{
    QListView* listView = qobject_cast< QListView* >(sender());
 
    QFileInfo fileInfo = model->fileInfo(index);
 
    if (fileInfo.fileName() == "..")
    {
        QDir dir = fileInfo.dir();
        dir.cdUp();
        listView->setRootIndex(model->index(dir.absolutePath()));
    }
    else if (fileInfo.fileName() == ".")
    {
        listView->setRootIndex(model->index(""));
    }
    else if (fileInfo.isDir())
    {
        listView->setRootIndex(index);
    }
    else if (fileInfo.completeSuffix() == "png" || fileInfo.completeSuffix() == "jpg")
    {
        hide();
        photoReaderWindow = new photoReader(fileInfo.absoluteFilePath());
        photoReaderWindow->exec();
        delete photoReaderWindow;
        show();
    }
 
}

void MainWindow::on_pushButton_clicked()
{
    hide();
    photoReaderWindow = new photoReader("/Users/kv/Pictures/oboi_5.jpg");
    photoReaderWindow->exec();
    delete photoReaderWindow;
    show();
}