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# chat.cpp Example File

dbus/dbus-chat/chat.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,
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     #include "chat.h"
     #include <QtGui/QApplication>
     #include <QtGui/QMessageBox>

     #include "chat_adaptor.h"
     #include "chat_interface.h"

     ChatMainWindow::ChatMainWindow()
         : m_nickname(QLatin1String("nickname"))
     {
         setupUi(this);
         sendButton->setEnabled(false);

         connect(messageLineEdit, SIGNAL(textChanged(QString)),
                 this, SLOT(textChangedSlot(QString)));
         connect(sendButton, SIGNAL(clicked(bool)), this, SLOT(sendClickedSlot()));
         connect(actionChangeNickname, SIGNAL(triggered(bool)), this, SLOT(changeNickname()));
         connect(actionAboutQt, SIGNAL(triggered(bool)), this, SLOT(aboutQt()));
         connect(qApp, SIGNAL(lastWindowClosed()), this, SLOT(exiting()));

         // add our D-Bus interface and connect to D-Bus
         new ChatAdaptor(this);
         QDBusConnection::sessionBus().registerObject("/", this);

         com::trolltech::chat *iface;
         iface = new com::trolltech::chat(QString(), QString(), QDBusConnection::sessionBus(), this);
         //connect(iface, SIGNAL(message(QString,QString)), this, SLOT(messageSlot(QString,QString)));
         QDBusConnection::sessionBus().connect(QString(), QString(), "com.trolltech.chat", "message", this, SLOT(messageSlot(QString,QString)));
         connect(iface, SIGNAL(action(QString,QString)), this, SLOT(actionSlot(QString,QString)));

         NicknameDialog dialog;
         dialog.cancelButton->setVisible(false);
         dialog.exec();
         m_nickname = dialog.nickname->text().trimmed();
         emit action(m_nickname, QLatin1String("joins the chat"));
     }

     ChatMainWindow::~ChatMainWindow()
     {
     }

     void ChatMainWindow::rebuildHistory()
     {
         QString history = m_messages.join( QLatin1String("\n" ) );
         chatHistory->setPlainText(history);
     }

     void ChatMainWindow::messageSlot(const QString &nickname, const QString &text)
     {
         QString msg( QLatin1String("<%1> %2") );
         msg = msg.arg(nickname, text);
         m_messages.append(msg);

         if (m_messages.count() > 100)
             m_messages.removeFirst();
         rebuildHistory();
     }

     void ChatMainWindow::actionSlot(const QString &nickname, const QString &text)
     {
         QString msg( QLatin1String("* %1 %2") );
         msg = msg.arg(nickname, text);
         m_messages.append(msg);

         if (m_messages.count() > 100)
             m_messages.removeFirst();
         rebuildHistory();
     }

     void ChatMainWindow::textChangedSlot(const QString &newText)
     {
         sendButton->setEnabled(!newText.isEmpty());
     }

     void ChatMainWindow::sendClickedSlot()
     {
         //emit message(m_nickname, messageLineEdit->text());
         QDBusMessage msg = QDBusMessage::createSignal("/", "com.trolltech.chat", "message");
         msg << m_nickname << messageLineEdit->text();
         QDBusConnection::sessionBus().send(msg);
         messageLineEdit->setText(QString());
     }

     void ChatMainWindow::changeNickname()
     {
         NicknameDialog dialog(this);
         if (dialog.exec() == QDialog::Accepted) {
             QString old = m_nickname;
             m_nickname = dialog.nickname->text().trimmed();
             emit action(old, QString("is now known as %1").arg(m_nickname));
         }
     }

     void ChatMainWindow::aboutQt()
     {
         QMessageBox::aboutQt(this);
     }

     void ChatMainWindow::exiting()
     {
         emit action(m_nickname, QLatin1String("leaves the chat"));
     }

     NicknameDialog::NicknameDialog(QWidget *parent)
         : QDialog(parent)
     {
         setupUi(this);
     }

     int main(int argc, char **argv)
     {
         QApplication app(argc, argv);

         if (!QDBusConnection::sessionBus().isConnected()) {
             qWarning("Cannot connect to the D-Bus session bus.\n"
                      "Please check your system settings and try again.\n");
             return 1;
         }

         ChatMainWindow chat;
         chat.show();
         return app.exec();
     }