QT实现文本编辑器

一 用 Qt4实现 的 文本 编辑器 
1. 新建 ，打开 ，保存 文件 
2.基本 的 文本 编辑功能 （复制 ， 粘贴 ， 剪切 等 )
3.不同 风格 
4.改变 文字 的 大小， 颜色 ，字体 等

界面 如下 ：

二 工程 文件 
1. /* src.pro*/
TEMPLATE = app
CONFIG += warn_on \
    thread \
          qt \
qtestlib
TARGET = texteditor
DESTDIR = ../bin
SOURCES += CMainWindow.cpp \
MainWindow.cpp \
CFindDialog.cpp
HEADERS += CFindDialog.h \
CMainWindow.h \
ui_finddialog.h \
ui_MainWindow.h
FORMS += FindDialog.ui \
MainWindow.ui
RESOURCES += MainWindow.qrc

QT += qt3support
2. /*CMainWindow.cpp*/

#include "CMainWindow.h"
#include "CFindDialog.h"
#include
#include

CMainWindow::CMainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    setupUi(this);
    iniStatusBar();
    iniConnect();
        fontColorAct = new QAction(QPixmap(32, 32), tr("改变字体颜色"), this);
        styleToolBar = new QToolBar(this);
        styleToolBar->setObjectName(QString::fromUtf8("styleToolBar"));
        styleToolBar->setOrientation(Qt::Horizontal);
        this->addToolBar(Qt::TopToolBarArea, styleToolBar);
        menu_2->addAction(fontColorAct);
        styleToolBar->addAction(fontColorAct);
    show();
        connect(fontColorAct, SIGNAL(triggered()), this, SLOT(changeColor()));
}

void CMainWindow::iniConnect()
{
    connect(textEdit, SIGNAL(cursorPositionChanged()), 
        this, SLOT(doCursorChanged()));
    connect(textEdit->document(), SIGNAL(contentsChanged()), 
        this, SLOT(doModified()));
    connect(actionAbout, SIGNAL(triggered()), this, SLOT(doAbout()));
    connect(actionHelp, SIGNAL(triggered()), this, SLOT(doHelp()));
    connect(actionQuit, SIGNAL(triggered()), this, SLOT(doQuit()));
    connect(actionOpen, SIGNAL(triggered()), this, SLOT(doOpen()));
    connect(actionAll, SIGNAL(triggered()), this, SLOT(doAll()));
    connect(actionASave, SIGNAL(triggered()), this, SLOT(doASave()));
    connect(actionClose, SIGNAL(triggered()), this, SLOT(doClose()));
    connect(actionCopy, SIGNAL(triggered()), this, SLOT(doCopy()));
    connect(actionUndo, SIGNAL(triggered()), this, SLOT(doUndo()));
    connect(actionRedo, SIGNAL(triggered()), this, SLOT(doRedo()));
    connect(actionSave, SIGNAL(triggered()), this, SLOT(doSave()));
    connect(actionFind, SIGNAL(triggered()), this, SLOT(doFind()));
    connect(actionNew, SIGNAL(triggered()), this, SLOT(doNew()));
    connect(actionPaste, SIGNAL(triggered()), this, SLOT(doPaste()));
    connect(actionCut, SIGNAL(triggered()), this, SLOT(doCut()));
    connect(actionWindows, SIGNAL(triggered()), this, SLOT(doWindows()));
    connect(actionWindowsXp, SIGNAL(triggered()), this, SLOT(doWindowsXp()));
    connect(actionCDE, SIGNAL(triggered()), this, SLOT(doCDE()));
    connect(actionMotif, SIGNAL(triggered()), this, SLOT(doMotif()));
    connect(actionPlastique, SIGNAL(triggered()), this, SLOT(doPlastique()));
    connect(actionFont, SIGNAL(triggered()), this, SLOT(doFont()));
}

void CMainWindow::changeColor()
{
QColor color =QColorDialog::getColor(fontColor, this);
if(color.isValid()) {
    fontColor = color;
    updateColor();
}

textEdit->setTextColor(fontColor);
}

void CMainWindow::doModified()
{
    setWindowModified(textEdit->document()->isModified());
    label2->setText("正在修改");
}

void CMainWindow::doAbout()
{
    QMessageBox::about(this,
                        "关于",
                        "TextEditor 1.0\nBy   Roc\nJune-15th-2009");
}

void CMainWindow::doHelp()
{
    QString info;
    QFile file("help.txt");
    if (!file.open(QFile::ReadOnly | QFile::Text))
    {
        QMessageBox::warning(this, 
                        "打开帮助文档",
                        QString("无法读取帮助文件:\n%1")
                                .arg(file.errorString()));
        return ;
    }
    else
    {
        QTextStream in(&file);
        QMessageBox box(this);
        box.setWindowTitle("帮助");
        box.setIcon(QMessageBox::Information);
        box.setText("TextEditor简介：");
        box.setStandardButtons(QMessageBox::Ok);
        box.setDetailedText(in.readAll());
        box.exec();
        return ;
    }
}

void CMainWindow::iniStatusBar()
{
    label1 = new QLabel;
    label1->setMinimumSize(200, 25);
    label1->setFrameShadow(QFrame::Sunken);
    label1->setFrameShape(QFrame::WinPanel);
    label2 = new QLabel;
    label2->setMinimumSize(200, 25);
    label2->setFrameShadow(QFrame::Sunken);
    label2->setFrameShape(QFrame::WinPanel);
    statusbar->addWidget(label1);
    statusbar->addWidget(label2);
}

void CMainWindow::doASave()
{
    QString filename = 
        QFileDialog::getSaveFileName(this, 
        "另存为", currentFile, "text files *.txt");
    if (!filename.isEmpty())
    {
        saveFile(filename);
    }
}

void CMainWindow::doCut()
{
    textEdit->cut();
}

void CMainWindow::doCopy()
{
    textEdit->copy();
}

void CMainWindow::doClose()
{
    maybeSave();
    textEdit->setVisible(false);
}

void CMainWindow::doNew()
{
    maybeSave();
    isUntited = true;
    currentFile = "Untited";
    setWindowTitle(currentFile + "[*]");
    textEdit->clear();
    textEdit->setVisible(true);
    setWindowModified(false);
}

void CMainWindow::doOpen()
{
    QString fileName = QFileDialog::getOpenFileName(this, 
        "打开文本", QDir::currentPath(), "text files *.txt");
    if (!fileName.isEmpty())
    {
        maybeSave();
        if (loadFile(fileName))
        {
            label2->setText("已读取");
        }
    }
    textEdit->setVisible(true);
}

void CMainWindow::doUndo()
{
    textEdit->undo();
}


void CMainWindow::doRedo()
{
    textEdit->redo();
}

void CMainWindow::doPaste()
{
    textEdit->paste();
}

void CMainWindow::doAll()
{
    textEdit->selectAll();
}

void CMainWindow::doSave()
{
    if (isUntited)
    {
        doASave();
    }
    else
    {
        saveFile(currentFile);
    }
}

void CMainWindow::doFind()
{
    CFindDialog *finddlg = new CFindDialog(0);
    finddlg->bolding(textEdit);
    finddlg->show();
}

void CMainWindow::doQuit()
{
    doClose();
    delete textEdit;
    textEdit = NULL;
    qApp->quit();
}

bool CMainWindow::loadFile(const QString &fileName)
{
    QFile file(fileName);
    if (!file.open(QFile::ReadOnly | QFile::Text))
    {
        QMessageBox::warning(this, 
                            "读取文件",
                            QString("无法读取文件%1:\n%2")
                            .arg(fileName)
                            .arg(file.errorString()));
        return false;
    }
    else
    {
        QTextStream in(&file);
        QApplication::setOverrideCursor(Qt::WaitCursor);
        textEdit->setText(in.readAll());
        QApplication::restoreOverrideCursor();
        setCurrentFile(fileName);
        return true;
    }
}


void CMainWindow::setCurrentFile(const QString &fileName)
{
    currentFile = QFileInfo(fileName).canonicalFilePath();
    isUntited = false;
    setWindowTitle(currentFile + "[*]");
    textEdit->document()->setModified(false);
    setWindowModified(false);
}

bool CMainWindow::saveFile(const QString fileName)
{
    QFile file(fileName);
    if (!file.open(QFile::WriteOnly | QFile::Text))
    {
        QMessageBox::warning(this, 
                            "保存文件",
                            QString("无法保存文件 %1:\n%2")
                            .arg(fileName)
                            .arg(file.errorString()));
        return false;
    }
    QTextStream out(&file);
    QApplication::setOverrideCursor(Qt::WaitCursor);
    out<toPlainText();
    QApplication::restoreOverrideCursor();
    setCurrentFile(fileName);
    label2->setText("已保存");
    return true;
}

void CMainWindow::doWindows()
{
    qApp->setStyle("windows");
}

void CMainWindow::doWindowsXp()
{
    qApp->setStyle("windowsxp");
}

void CMainWindow::doMotif()
{
    qApp->setStyle("motif");
}

void CMainWindow::doCDE()
{
    qApp->setStyle("cde");
}

void CMainWindow::doPlastique()
{
    qApp->setStyle("plastique");
}

void CMainWindow::doFont()
{
    bool ok;
    QFont font = QFontDialog::getFont(&ok,textEdit->font(),this,"字体对话框");
    if (ok)
    {
        textEdit->setFont(font);
    }
}

void CMainWindow::maybeSave()
{
    if (textEdit->document()->isModified())
    {
        QMessageBox box;
        box.setWindowTitle("警告");
        box.setIcon(QMessageBox::Warning);
        box.setText("文档未保存，是否保存？");
        box.setStandardButtons(QMessageBox::Yes | QMessageBox::No);
        if (box.exec() == QMessageBox::Yes)
        {
            doSave();
        }
    }
}

void CMainWindow::doCursorChanged()
{
    int pageNum = textEdit->document()->pageCount();
    const QTextCursor cursor = textEdit->textCursor();
    int colNum = cursor.columnNumber();
    int rowNum = textEdit->document()->blockCount();
    label1->setText(QString("%1页 %2行 %3列").arg(pageNum).arg(rowNum).arg(colNum));
}

void CMainWindow::updateColor()
{
QPixmap pixmap(32, 32);
QPainter painter(&pixmap);
painter.fillRect(0, 0, 32, 32, fontColor);

QColor lighter = fontColor.light();
painter.setPen(lighter);
QPoint lightFrame[] = {QPoint(0, 31), QPoint(0, 0), QPoint(31, 0) };
painter.drawPolyline(lightFrame, 3);

painter.setPen(fontColor.dark());
QPoint darkFrame[] = {QPoint(1, 31), QPoint(31, 31), QPoint(31, 1) };
painter.drawPolyline(darkFrame, 3);
painter.end();

fontColorAct->setIcon(pixmap);

}