blockingclient.cpp Example File

 /****************************************************************************
 **
 ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
 ** All rights reserved.
 ** Contact: Nokia Corporation (qt-info@nokia.com)
 **
 ** This file is part of the examples of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:BSD$
 ** You may use this file under the terms of the BSD license as follows:
 **
 ** "Redistribution and use in source and binary forms, with or without
 ** modification, are permitted provided that the following conditions are
 ** met:
 **   * Redistributions of source code must retain the above copyright
 **     notice, this list of conditions and the following disclaimer.
 **   * Redistributions in binary form must reproduce the above copyright
 **     notice, this list of conditions and the following disclaimer in
 **     the documentation and/or other materials provided with the
 **     distribution.
 **   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
 **     the names of its contributors may be used to endorse or promote
 **     products derived from this software without specific prior written
 **     permission.
 **
 ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #include <QtGui>
 #include <QtNetwork>

 #include "blockingclient.h"

 BlockingClient::BlockingClient(QWidget *parent)
     : QDialog(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."));

     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(hostLineEdit, SIGNAL(textChanged(QString)),
             this, SLOT(enableGetFortuneButton()));
     connect(portLineEdit, SIGNAL(textChanged(QString)),
             this, SLOT(enableGetFortuneButton()));
     connect(getFortuneButton, SIGNAL(clicked()),
             this, SLOT(requestNewFortune()));
     connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));
     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()
 {
     getFortuneButton->setEnabled(!hostLineEdit->text().isEmpty()
                                  && !portLineEdit->text().isEmpty());
 }