chatdialog.cpp Example File

 /****************************************************************************
 **
 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
 ** All rights reserved.
 ** Contact: Nokia Corporation ([email protected])
 **
 ** 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 "chatdialog.h"

 ChatDialog::ChatDialog(QWidget *parent)
     : QDialog(parent)
 {
     setupUi(this);

     lineEdit->setFocusPolicy(Qt::StrongFocus);
     textEdit->setFocusPolicy(Qt::NoFocus);
     textEdit->setReadOnly(true);
     listWidget->setFocusPolicy(Qt::NoFocus);

     connect(lineEdit, SIGNAL(returnPressed()), this, SLOT(returnPressed()));
     connect(lineEdit, SIGNAL(returnPressed()), this, SLOT(returnPressed()));
     connect(&client, SIGNAL(newMessage(QString,QString)),
             this, SLOT(appendMessage(QString,QString)));
     connect(&client, SIGNAL(newParticipant(QString)),
             this, SLOT(newParticipant(QString)));
     connect(&client, SIGNAL(participantLeft(QString)),
             this, SLOT(participantLeft(QString)));

     myNickName = client.nickName();
     newParticipant(myNickName);
     tableFormat.setBorder(0);
     QTimer::singleShot(10 * 1000, this, SLOT(showInformation()));
 }

 void ChatDialog::appendMessage(const QString &from, const QString &message)
 {
     if (from.isEmpty() || message.isEmpty())
         return;

     QTextCursor cursor(textEdit->textCursor());
     cursor.movePosition(QTextCursor::End);
     QTextTable *table = cursor.insertTable(1, 2, tableFormat);
     table->cellAt(0, 0).firstCursorPosition().insertText('<' + from + "> ");
     table->cellAt(0, 1).firstCursorPosition().insertText(message);
     QScrollBar *bar = textEdit->verticalScrollBar();
     bar->setValue(bar->maximum());
 }

 void ChatDialog::returnPressed()
 {
     QString text = lineEdit->text();
     if (text.isEmpty())
         return;

     if (text.startsWith(QChar('/'))) {
         QColor color = textEdit->textColor();
         textEdit->setTextColor(Qt::red);
         textEdit->append(tr("! Unknown command: %1")
                          .arg(text.left(text.indexOf(' '))));
         textEdit->setTextColor(color);
     } else {
         client.sendMessage(text);
         appendMessage(myNickName, text);
     }

     lineEdit->clear();
 }

 void ChatDialog::newParticipant(const QString &nick)
 {
     if (nick.isEmpty())
         return;

     QColor color = textEdit->textColor();
     textEdit->setTextColor(Qt::gray);
     textEdit->append(tr("* %1 has joined").arg(nick));
     textEdit->setTextColor(color);
     listWidget->addItem(nick);
 }

 void ChatDialog::participantLeft(const QString &nick)
 {
     if (nick.isEmpty())
         return;

     QList<QListWidgetItem *> items = listWidget->findItems(nick,
                                                            Qt::MatchExactly);
     if (items.isEmpty())
         return;

     delete items.at(0);
     QColor color = textEdit->textColor();
     textEdit->setTextColor(Qt::gray);
     textEdit->append(tr("* %1 has left").arg(nick));
     textEdit->setTextColor(color);
 }

 void ChatDialog::showInformation()
 {
     if (listWidget->count() == 1) {
         QMessageBox::information(this, tr("Chat"),
                                  tr("Launch several instances of this "
                                     "program on your local network and "
                                     "start chatting!"));
     }
 }