blockingclient.cpp Example File

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  #include <QtWidgets>
  #include <QtNetwork>

  #include "blockingclient.h"

  BlockingClient::BlockingClient(QWidget *parent)
      : QWidget(parent)
  {
      hostLabel = new QLabel(tr("&Server name:"));
      portLabel = new QLabel(tr("S&erver port:"));

      // find out which IP to connect to
      QString ipAddress;
      QList<QHostAddress> ipAddressesList = QNetworkInterface::allAddresses();
      // use the first non-localhost IPv4 address
      for (int i = 0; i < ipAddressesList.size(); ++i) {
          if (ipAddressesList.at(i) != QHostAddress::LocalHost &&
              ipAddressesList.at(i).toIPv4Address()) {
              ipAddress = ipAddressesList.at(i).toString();
              break;
          }
      }
      // if we did not find one, use IPv4 localhost
      if (ipAddress.isEmpty())
          ipAddress = QHostAddress(QHostAddress::LocalHost).toString();

      hostLineEdit = new QLineEdit(ipAddress);
      portLineEdit = new QLineEdit;
      portLineEdit->setValidator(new QIntValidator(1, 65535, this));

      hostLabel->setBuddy(hostLineEdit);
      portLabel->setBuddy(portLineEdit);

      statusLabel = new QLabel(tr("This examples requires that you run the "
                                  "Fortune Server example as well."));
      statusLabel->setWordWrap(true);

      getFortuneButton = new QPushButton(tr("Get Fortune"));
      getFortuneButton->setDefault(true);
      getFortuneButton->setEnabled(false);

      quitButton = new QPushButton(tr("Quit"));

      buttonBox = new QDialogButtonBox;
      buttonBox->addButton(getFortuneButton, QDialogButtonBox::ActionRole);
      buttonBox->addButton(quitButton, QDialogButtonBox::RejectRole);

      connect(getFortuneButton, SIGNAL(clicked()), this, SLOT(requestNewFortune()));
      connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));

      connect(hostLineEdit, SIGNAL(textChanged(QString)),
              this, SLOT(enableGetFortuneButton()));
      connect(portLineEdit, SIGNAL(textChanged(QString)),
              this, SLOT(enableGetFortuneButton()));
      connect(&thread, SIGNAL(newFortune(QString)),
              this, SLOT(showFortune(QString)));
      connect(&thread, SIGNAL(error(int,QString)),
              this, SLOT(displayError(int,QString)));

      QGridLayout *mainLayout = new QGridLayout;
      mainLayout->addWidget(hostLabel, 0, 0);
      mainLayout->addWidget(hostLineEdit, 0, 1);
      mainLayout->addWidget(portLabel, 1, 0);
      mainLayout->addWidget(portLineEdit, 1, 1);
      mainLayout->addWidget(statusLabel, 2, 0, 1, 2);
      mainLayout->addWidget(buttonBox, 3, 0, 1, 2);
      setLayout(mainLayout);

      setWindowTitle(tr("Blocking Fortune Client"));
      portLineEdit->setFocus();
  }

  void BlockingClient::requestNewFortune()
  {
      getFortuneButton->setEnabled(false);
      thread.requestNewFortune(hostLineEdit->text(),
                               portLineEdit->text().toInt());
  }

  void BlockingClient::showFortune(const QString &nextFortune)
  {
      if (nextFortune == currentFortune) {
          requestNewFortune();
          return;
      }

      currentFortune = nextFortune;
      statusLabel->setText(currentFortune);
      getFortuneButton->setEnabled(true);
  }

  void BlockingClient::displayError(int socketError, const QString &message)
  {
      switch (socketError) {
      case QAbstractSocket::HostNotFoundError:
          QMessageBox::information(this, tr("Blocking Fortune Client"),
                                   tr("The host was not found. Please check the "
                                      "host and port settings."));
          break;
      case QAbstractSocket::ConnectionRefusedError:
          QMessageBox::information(this, tr("Blocking Fortune Client"),
                                   tr("The connection was refused by the peer. "
                                      "Make sure the fortune server is running, "
                                      "and check that the host name and port "
                                      "settings are correct."));
          break;
      default:
          QMessageBox::information(this, tr("Blocking Fortune Client"),
                                   tr("The following error occurred: %1.")
                                   .arg(message));
      }

      getFortuneButton->setEnabled(true);
  }

  void BlockingClient::enableGetFortuneButton()
  {
      bool enable(!hostLineEdit->text().isEmpty() && !portLineEdit->text().isEmpty());
      getFortuneButton->setEnabled(enable);
  }