blockingclient.cpp Example File

blockingfortuneclient/blockingclient.cpp
/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** 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 The Qt Company Ltd 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 <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);
}

© 2017 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.