Qt 4.8: blockingclient.cpp Example File (network/blockingfortuneclient/blockingclient.cpp)

Qt Reference Documentation

# blockingclient.cpp Example File

network/blockingfortuneclient/blockingclient.cpp

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     #include <QtGui>
     #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));

     #if defined(Q_OS_SYMBIAN) || defined(Q_WS_MAEMO_5) || defined(Q_WS_SIMULATOR)
         Qt::InputMethodHint hints = Qt::ImhDigitsOnly;
         portLineEdit->setInputMethodHints(hints);
     #endif

         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);

     #ifdef Q_OS_SYMBIAN
         QMenu *menu = new QMenu(this);
         fortuneAction = menu->addAction(tr("Get Fortune"));
         fortuneAction->setVisible(false);

         QAction *optionsAction = new QAction(tr("Options"), this);
         optionsAction->setMenu(menu);
         optionsAction->setSoftKeyRole(QAction::PositiveSoftKey);
         addAction(optionsAction);

         exitAction = new QAction(tr("Exit"), this);
         exitAction->setSoftKeyRole(QAction::NegativeSoftKey);
         addAction(exitAction);

         connect(fortuneAction, SIGNAL(triggered()), this, SLOT(requestNewFortune()));
         connect(exitAction, SIGNAL(triggered()), this, SLOT(close()));
     #else
         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()));
     #endif

         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);
     #ifndef Q_OS_SYMBIAN
         mainLayout->addWidget(buttonBox, 3, 0, 1, 2);
     #endif
         setLayout(mainLayout);

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

     void BlockingClient::requestNewFortune()
     {
     #ifdef Q_OS_SYMBIAN
         fortuneAction->setVisible(false);
     #else
         getFortuneButton->setEnabled(false);
     #endif
         thread.requestNewFortune(hostLineEdit->text(),
                                  portLineEdit->text().toInt());
     }

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

         currentFortune = nextFortune;
         statusLabel->setText(currentFortune);
     #ifdef Q_OS_SYMBIAN
         fortuneAction->setVisible(true);
     #else
         getFortuneButton->setEnabled(true);
     #endif
     }

     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));
         }

     #ifdef Q_OS_SYMBIAN
         fortuneAction->setVisible(true);
     #else
         getFortuneButton->setEnabled(true);
     #endif
     }

     void BlockingClient::enableGetFortuneButton()
     {
         bool enable(!hostLineEdit->text().isEmpty() && !portLineEdit->text().isEmpty());
     #ifdef Q_OS_SYMBIAN
         fortuneAction->setVisible(enable);
     #else
         getFortuneButton->setEnabled(enable);
     #endif
     }