textfinder.cpp Example File
uitools/textfinder/textfinder.cpp

 /****************************************************************************
 **
 ** Copyright (C) 2005-2008 Nokia Corporation and/or its subsidiary(-ies). All rights reserved.
 **
 ** This file is part of the documentation of the Qt Toolkit.
 **
 ** Licensees holding a valid Qt License Agreement may use this file in
 ** accordance with the rights, responsibilities and obligations
 ** contained therein.  Please consult your licensing agreement or
 ** contact qt-sales@nokia.com if any conditions of this licensing
 ** agreement are not clear to you.
 **
 ** Further information about Qt licensing is available at:
 ** http://trolltech.com/products/appdev/licensing.
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ****************************************************************************/

 #include <QtUiTools>
 #include <QtGui>
 #include "textfinder.h"

 TextFinder::TextFinder(QWidget *parent)
     : QWidget(parent)
 {
     QWidget *formWidget = loadUiFile();

     ui_findButton = qFindChild<QPushButton*>(this, "findButton");
     ui_textEdit = qFindChild<QTextEdit*>(this, "textEdit");
     ui_lineEdit = qFindChild<QLineEdit*>(this, "lineEdit");

     QMetaObject::connectSlotsByName(this);

     loadTextFile();

     QVBoxLayout *layout = new QVBoxLayout;
     layout->addWidget(formWidget);
     setLayout(layout);
     setWindowTitle(tr("Text Finder"));

     isFirstTime = true;
 }

 QWidget* TextFinder::loadUiFile()
 {
     QUiLoader loader;

     QFile file(":/forms/textfinder.ui");
     file.open(QFile::ReadOnly);

     QWidget *formWidget = loader.load(&file, this);
     file.close();

     return formWidget;
 }

 void TextFinder::loadTextFile()
 {
     QFile inputFile(":/forms/input.txt");
     inputFile.open(QIODevice::ReadOnly);
     QTextStream in(&inputFile);
     QString line = in.readAll();
     inputFile.close();

     ui_textEdit->append(line);
     ui_textEdit->setUndoRedoEnabled(false);
     ui_textEdit->setUndoRedoEnabled(true);
 }

 void TextFinder::on_findButton_clicked()
 {
     QString searchString = ui_lineEdit->text();
     QTextDocument *document = ui_textEdit->document();

     bool found = false;

     if (isFirstTime == false)
         document->undo();

     if (searchString == "") {
         QMessageBox::information(this, tr("Empty Search Field"),
                 "The search field is empty. Please enter a word and click Find.");
     } else {

         QTextCursor highlightCursor(document);
         QTextCursor cursor(document);

         cursor.beginEditBlock();

         QTextCharFormat plainFormat(highlightCursor.charFormat());
         QTextCharFormat colorFormat = plainFormat;
         colorFormat.setForeground(Qt::red);

         while (!highlightCursor.isNull() && !highlightCursor.atEnd()) {
             highlightCursor = document->find(searchString, highlightCursor, QTextDocument::FindWholeWords);

             if (!highlightCursor.isNull()) {
                 found = true;
                 highlightCursor.movePosition(QTextCursor::WordRight,
                                        QTextCursor::KeepAnchor);
                 highlightCursor.mergeCharFormat(colorFormat);
             }
         }

         cursor.endEditBlock();
         isFirstTime = false;

         if (found == false) {
             QMessageBox::information(this, tr("Word Not Found"),
                 "Sorry, the word cannot be found.");
         }
     }
 }