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
 }