#include <QtGui>#include "regexpmodel.h"#include "regexpparser.h"#include "regexpwindow.h"RegExpWindow::RegExpWindow(){    label = new QLabel(tr("Regular expression:"));    lineEdit = new QLineEdit;    regExpModel = new RegExpModel(this);    treeView = new QTreeView;    treeView->setModel(regExpModel);    connect(lineEdit, SIGNAL(textChanged(const QString &)),            this, SLOT(regExpChanged(const QString &)));    QGridLayout *layout = new QGridLayout;    layout->addWidget(label, 0, 0);    layout->addWidget(lineEdit, 0, 1);    layout->addWidget(treeView, 1, 0, 1, 2);    setLayout(layout);    setWindowTitle(tr("Regexp Parser"));}void RegExpWindow::regExpChanged(const QString &regExp){    RegExpParser parser;    Node *rootNode = parser.parse(regExp);    regExpModel->setRootNode(rootNode);}