mainwindow.cpp Example File

secureudpserver/mainwindow.cpp

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  #include "mainwindow.h"
  #include "nicselector.h"
  #include "ui_mainwindow.h"

  MainWindow::MainWindow()
      : ui(new Ui::MainWindow)
  {
      ui->setupUi(this);

      connect(&server, &DtlsServer::errorMessage, this, &MainWindow::addErrorMessage);
      connect(&server, &DtlsServer::warningMessage, this, &MainWindow::addWarningMessage);
      connect(&server, &DtlsServer::infoMessage, this, &MainWindow::addInfoMessage);
      connect(&server, &DtlsServer::datagramReceived, this, &MainWindow::addClientMessage);

      updateUi();
  }

  MainWindow::~MainWindow()
  {
      delete ui;
  }

  void MainWindow::on_startButton_clicked()
  {
      if (!server.isListening()) {
          NicSelector ipDialog;
          if (ipDialog.exec() == QDialog::Accepted) {
              const QHostAddress address = ipDialog.selectedIp();
              const quint16 port = ipDialog.selectedPort();
              if (address.isNull()) {
                  addErrorMessage(tr("Failed to start listening, no valid address/port"));
              } else if (server.listen(address, port)) {
                  addInfoMessage(tr("Server is listening on address %1 and port %2")
                                   .arg(address.toString())
                                   .arg(port));
              }
          }
      } else {
          server.close();
          addInfoMessage(tr("Server is not accepting new connections"));
      }

      updateUi();
  }

  void MainWindow::on_quitButton_clicked()
  {
      QCoreApplication::exit(0);
  }

  void MainWindow::updateUi()
  {
      server.isListening() ? ui->startButton->setText(tr("Stop listening"))
                           : ui->startButton->setText(tr("Start listening"));
  }

  const QString colorizer(QStringLiteral("<font color=\"%1\">%2</font><br>"));

  void MainWindow::addErrorMessage(const QString &message)
  {
      ui->serverInfo->insertHtml(colorizer.arg(QStringLiteral("Crimson"), message));
  }

  void MainWindow::addWarningMessage(const QString &message)
  {
      ui->serverInfo->insertHtml(colorizer.arg(QStringLiteral("DarkOrange"), message));
  }

  void MainWindow::addInfoMessage(const QString &message)
  {
      ui->serverInfo->insertHtml(colorizer.arg(QStringLiteral("DarkBlue"), message));
  }

  void MainWindow::addClientMessage(const QString &peerInfo, const QByteArray &datagram,
                                    const QByteArray &plainText)
  {
      static const QString messageColor = QStringLiteral("DarkMagenta");
      static const QString formatter = QStringLiteral("<br>---------------"
                                                      "<br>A message from %1"
                                                      "<br>DTLS datagram:<br> %2"
                                                      "<br>As plain text:<br> %3");

      const QString html = formatter.arg(peerInfo, QString::fromUtf8(datagram.toHex(' ')),
                                         QString::fromUtf8(plainText));
      ui->messages->insertHtml(colorizer.arg(messageColor, html));
  }