qt文本编辑器

示例代码：

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QtGui>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    isSaved =false;
    curFile = tr("未命名.txt");
    setWindowTitle(curFile);
    init_statusBar();
}

MainWindow::~MainWindow()
{
    delete ui;
}


void MainWindow::do_file_New()
{
    do_file_SaveOrNot();
    isSaved = false;
    curFile = tr("未命名.txt");
    setWindowTitle(curFile);
    ui->textEdit->clear();//清空文本编辑器
    ui->textEdit->setVisible(true);//文本编辑器可见
}

void MainWindow::do_file_SaveOrNot()
{
    if(ui->textEdit->document()->isModified()) //如果文件被更改过，弹出保存对话框
    {
        QMessageBox box;
        box.setWindowTitle(tr("警告"));
        box.setIcon(QMessageBox::Warning);
        box.setText(curFile+tr("尚未保存，是否保存？"));
        box.setStandardButtons(QMessageBox::Yes|QMessageBox::No);
        if(box.exec() == QMessageBox::Yes)
            do_file_Save();
    }
}

void MainWindow::do_file_Save()
{
    if(isSaved)
    {
        saveFile(curFile);
    }
    else
    {
        do_file_SaveAs();
    }
}

void MainWindow::do_file_SaveAs()
{
  //  QString fileName = QFileDialog::getSaveFileName(this,tr("另存为")，curFile);
      QString fileName = QFileDialog::getSaveFileName(this,tr("另存为"),curFile);

    if(!fileName.isEmpty())
    {
        saveFile(fileName);
    }

}

bool MainWindow::saveFile(const QString &fileName)
{
    QFile file(fileName);
    if(!file.open(QFile::WriteOnly|QFile::Text))
    {
        QMessageBox::warning(this,tr("保存文件"),
        tr("无法保存文件 %1:
 %2").arg(fileName)
        .arg(file.errorString()));

        return false;
    }

    QTextStream out(&file);
    out<<ui->textEdit->toPlainText();
    isSaved = true;
    curFile = QFileInfo(fileName).canonicalFilePath();
    setWindowTitle(curFile);
    return true;
}


void MainWindow::do_file_Open()
{
    do_file_SaveOrNot();
    QString fileName = QFileDialog::getOpenFileName(this);
    if(!fileName.isEmpty())
    {
        do_file_Load(fileName);
    }

    ui->textEdit->setVisible(true);//文本编辑器可见
}

bool MainWindow::do_file_Load(const QString &fileName)
{
    QFile file(fileName);
    if(!file.open(QFile::ReadOnly|QFile::Text))
    {
        QMessageBox::warning(this,tr("读取文件"),tr("无法读取文件 %1:
%2").arg(fileName).arg(file.errorString()));
        return false;
    }

    QTextStream in(&file);
    ui->textEdit->setText(in.readAll());
    curFile = QFileInfo(fileName).canonicalFilePath();
    setWindowTitle(curFile);
    return true;

}

void MainWindow::on_action_N_triggered()
{
    do_file_New();
}

void MainWindow::on_action_S_triggered()
{
    do_file_Save();
}

void MainWindow::on_action_2_triggered()
{
    do_file_SaveAs();
}

void MainWindow::on_action_O_triggered()
{
    do_file_Open();
}

void MainWindow::on_action_C_triggered()
{
    do_file_SaveOrNot();
    ui->textEdit->setVisible(false);
}



void MainWindow::on_action_X_triggered()
{
    on_action_C_triggered();
    qApp->quit();
}

void MainWindow::on_action_Z_triggered()
{
    ui->textEdit->undo();
}

void MainWindow::on_action_X_2_triggered()
{
    ui->textEdit->cut();
}

void MainWindow::on_action_C_2_triggered()
{
    ui->textEdit->copy();
}

void MainWindow::on_action_V_triggered()
{
    ui->textEdit->paste();
}

void MainWindow::on_action_F_triggered()
{
    QDialog *findDlg = new QDialog(this);
    findDlg ->setWindowTitle(tr("查找"));
    find_textLineEdit = new QLineEdit(findDlg);
    QPushButton *find_Btn = new QPushButton(tr("查找下一个"),findDlg);
    QVBoxLayout *layout = new  QVBoxLayout(findDlg);
    layout ->addWidget(find_textLineEdit);
    layout->addWidget(find_Btn);
    findDlg ->show();
    //显示对话框
    connect(find_Btn,SIGNAL(clicked()),this,SLOT(show_findText()));


}


void MainWindow::show_findText()
{
    QString findText = find_textLineEdit->text();
    ui->textEdit->find(findText,QTextDocument::FindBackward);
    if(!ui->textEdit->find(findText,QTextDocument::FindBackward))
    {
        QMessageBox::warning(this,tr("查找"),tr("找不到 %1").arg(findText));
    }

}

void MainWindow::init_statusBar()
{
    QStatusBar*bar = ui->statusBar;
    first_statusLabel = new QLabel;
    first_statusLabel -> setMinimumSize(150,20);
    first_statusLabel -> setFrameShape(QFrame::WinPanel);
    first_statusLabel -> setFrameShadow(QFrame::Sunken);
    second_statusLabel = new QLabel;
    second_statusLabel->setMinimumSize(150,20);
    second_statusLabel ->setFrameShape(QFrame::WinPanel);

    second_statusLabel->setFrameShadow(QFrame::Sunken);
    bar ->addWidget(first_statusLabel);
    bar->addWidget(second_statusLabel);
    first_statusLabel->setText(tr("欢迎使用文本编辑器"));
    second_statusLabel->setText("yafeilinux 制作！");

}