qt5.5实现 记事本程序

最近由于要做Qt相关的毕业设计课题，以前对Qt完全不了解，对于客户端图形界面程序，也只对Windows下的MFC熟悉，

所以，由于Qt的跨平台特性和相对比较纯的C++的特点，就准备学习一下吧。这两天逛了一下Qt的开发者官方网站，和一些国内的论坛，

看了下基本的知识点，比如信号和槽的机制，界面的布局，就想写个东西，巩固一下。于是参考了官方的文档和代码，纯代码实现了一个简易的记事本程序。

希望大家参考学习，共同进步。不足之处，还请指出。

记事本简介：记事本采用代码实现GUI界面，支持，新建，保存，另存为，查找，替换，打印功能。

开发环境：win7旗舰版 32位 Qt Creator   Qt 5.5

参考资料：http://www.devbean.net/2012/08/qt-study-road-2-intro

http://doc.qt.io/qt-5/gettingstartedqt.html

界面外观：

查找功能：

替换功能：

打印功能：

保存等：

关于本屌狮

本程序涉及一个主对话框，一个查找对话框，一个替换对话框，一个打印对话框，一个关于信息对话框，一个打开对话框，一个保存对话框，其他信息提示对话框。

功能设计：主要涉及对话框的布局，主对话框与查找，替换对话框的交互。当然这是通过信号与槽的机制来实现的。下面看下具体的代码实现。

主对话框类

 #ifndef MAINWINDOW_H
 #define MAINWINDOW_H

 #include <QMainWindow>
 #include <QMenu>
 #include <QMenuBar>
 #include <QAction>
 #include <QTextEdit>
 #include <QIcon>
 #include <QFile>
 #include <QFileDialog>
 #include <QTextStream>
 #include <QMessageBox>
 #include <QTextDocument>
 #include <QTextCursor>
 #include <QToolBar>
 #include <QtPrintSupport/QPrinter>
 #include <QtPrintSupport/QPrintDialog>
 #include <QtPrintSupport/QPrintPreviewDialog>
 #include <QtPrintSupport/QPageSetupDialog>

 #include <finddialog.h>

 #include <replacedialog.h>

 class MainWindow : public QMainWindow
 {
     Q_OBJECT
 public:
     MainWindow(QWidget *parent = );
     ~MainWindow();
 protected:
 private slots:
     void createMenus();
     void createActions();
     void newAct();
     void openAct();
     void saveAct();
     void printAct();
     void exitAct();
     void findAct(QString,bool,bool);
     void aboutAct();
     void anotherSaveAct();
     void showFindDialog();
     void showReplaceDialog();
     void findReplace(QString,bool);
     void replaceCur(QString,QString);
     void replaceAll(QString,QString,bool);

 private:
     //菜单
     bool   find;
     QMenu *file_menu;
     QMenu *edit_menu;
     QMenu *about_menu;
     //Action响应file_menu
     QAction *new_act;
     QAction *open_act;
     QAction *save_act;
     QAction *another_save_act;
     QAction *print_act;
     QAction *exit_act;
     //Action响应edit_menu
     QAction *find_act;
     QAction *replace_act;
     //Action响应help_menu
     QAction *about_act;
     //Edit
     QTextEdit *mini_text;

     FindDialog *find_dialog;
     ReplaceDialog *replace_dialog;
     QString cur_file_name;

 };

 #endif // MAINWINDOW_H

 #include "mainwindow.h"
 MainWindow::MainWindow(QWidget *parent)
     : QMainWindow(parent)
 {
     setWindowTitle(tr("MiniText"));
     mini_text = new QTextEdit;
     this->setCentralWidget(mini_text);
     resize(,);
     cur_file_name = tr("");

     createActions();
     createMenus();
 }

 MainWindow::~MainWindow()
 {
    if(file_menu){
        delete file_menu;
    }
    if(edit_menu){
        delete edit_menu;
    }
    if(about_menu){
        delete about_menu;
    }
    if(new_act){
        delete new_act;
    }
    if(open_act){
        delete open_act;
    }
    if(save_act){
        delete save_act;
    }
    if(print_act){
        delete print_act;
    }
    if(exit_act){
        delete exit_act;

    }
    if(find_act){
        delete find_act;

    }
    if(replace_act){
        delete replace_act;
    }
    if(about_act){
        delete about_act;
    }
    if(mini_text){
        delete mini_text;
    }
    if(find_dialog){
        delete find_dialog;
    }
    if(replace_dialog){
        delete replace_dialog;
    }
    if(another_save_act){
        delete another_save_act;
    }
 }

 void MainWindow::createMenus()
 {

     file_menu = menuBar()->addMenu(tr("&文件"));
     file_menu->setStyleSheet("color:blue");
     file_menu->addAction(new_act);
     file_menu->addAction(open_act);
     file_menu->addAction(save_act);
     file_menu->addAction(another_save_act);
     file_menu->addAction(print_act);
     file_menu->addSeparator();
     file_menu->addAction(exit_act);
     edit_menu = menuBar()->addMenu(tr("&编辑"));
     edit_menu->setStyleSheet("color:blue");
     edit_menu->addAction(find_act);
     edit_menu->addAction(replace_act);
     about_menu = menuBar()->addMenu(tr("&关于"));
     about_menu->setStyleSheet("color:blue");
     about_menu->addAction(about_act);
     QToolBar *tool_bar = addToolBar(tr("file"));
     tool_bar->addAction(new_act);
     tool_bar->addAction(open_act);
     tool_bar->addAction(save_act);
     tool_bar->addAction(another_save_act);
     tool_bar->addAction(print_act);
     tool_bar->addAction(find_act);
     tool_bar->addAction(replace_act);
     tool_bar->addAction(about_act);
     tool_bar->addAction(exit_act);

 }

 void MainWindow::createActions()
 {
     find = false;
     find_dialog = new FindDialog(this);
     replace_dialog = new ReplaceDialog(this);
     //Action响应file_menu
     new_act = new QAction(QIcon(tr(":/images/new")),tr("&新建"),this);
     new_act->setShortcut(QKeySequence::New);

     open_act = new QAction(QIcon(tr(":/images/open")),tr("&打开"),this);
     open_act->setShortcut(QKeySequence::Open);

     save_act = new QAction(QIcon(tr(":/images/save")),tr("&保存"),this);
     save_act->setShortcut(QKeySequence::Save);

     another_save_act = new QAction(QIcon(tr(":/images/another_save")),tr("另存为"),this);

     print_act = new QAction(QIcon(tr(":/images/print")),tr("&打印"),this);
     print_act->setShortcut(QKeySequence::Print);

     exit_act = new QAction(QIcon(tr(":/images/exit")),tr("&退出"),this);
     exit_act->setShortcut(QKeySequence::Quit);

     find_act = new QAction(QIcon(tr(":/images/find")),tr("&查找"),this);
     find_act->setShortcut(QKeySequence::Find);

     replace_act = new QAction(QIcon(tr(":/images/replace")),tr("&替换"),this);
     replace_act->setShortcut(QKeySequence::Replace);

     about_act = new QAction(QIcon(tr(":/images/about")),tr("关于"),this);

     connect(new_act,SIGNAL(triggered()),this,SLOT(newAct()));
     connect(open_act,SIGNAL(triggered()),this,SLOT(openAct()));
     connect(save_act,SIGNAL(triggered()),this,SLOT(saveAct()));
     connect(print_act,SIGNAL(triggered()),this,SLOT(printAct()));
     connect(another_save_act,SIGNAL(triggered()),this,SLOT(anotherSaveAct()));
     connect(exit_act,SIGNAL(triggered()),this,SLOT(exitAct()));
     connect(find_act,SIGNAL(triggered()),this,SLOT(showFindDialog()));
     connect(replace_act,SIGNAL(triggered()),this,SLOT(showReplaceDialog()));
     connect(about_act,SIGNAL(triggered()),this,SLOT(aboutAct()));

     connect(find_dialog,SIGNAL(findTextDataButtonClickedSignal(QString,bool,bool)),
             this,SLOT(findAct(QString,bool,bool)));
     connect(replace_dialog,SIGNAL(findReplaceStr(QString,bool)),
             this,SLOT(findReplace(QString,bool)));
     connect(replace_dialog,SIGNAL(replaceCurOneStr(QString,QString)),
             this,SLOT(replaceCur(QString,QString)));
     connect(replace_dialog,SIGNAL(replaceAllStr(QString,QString,bool)),
             this,SLOT(replaceAll(QString,QString,bool)));
 }

 void MainWindow::newAct()
 {
     if (mini_text->document()->isModified())
     {
         QMessageBox::StandardButton button = QMessageBox::information(this,
                                           "尚未保存", "是否要保存?",QMessageBox::Save |
                                            QMessageBox::Discard | QMessageBox::Cancel);
         switch(button)
         {
             case QMessageBox::Save:{
                 saveAct();
                 if (mini_text->document()->isModified()){
                     return;
                 }
             }
             case QMessageBox::Cancel:{
                 return;
             }
             case QMessageBox::Discard:{
                 break;
             }
         }
     }
     mini_text->clear();
 }

 //打开文件
 void MainWindow::openAct()
 {
     QString file_name = QFileDialog::getOpenFileName(this,tr("打开文件"),QString(),
                           tr("文本文件(*.txt) ;; C++文件(*.h *.cpp *.hpp)"));
     cur_file_name = file_name;
     if(!file_name.isEmpty()){
        QFile file(file_name);
        if(!file.open(QIODevice::ReadOnly)){
           QMessageBox::critical(this,tr("错误"),tr("不能打开文件"));
           return;
        }
        QTextStream ins(&file);
        mini_text->setText(ins.readAll());
        file.close();
     }
 }

 //保存文件
 void MainWindow::saveAct()
 {
     if(cur_file_name.isEmpty()){
         QString file_name = QFileDialog::getSaveFileName(this,tr("保存文件"),QString(),
                                tr("文本文件(*.txt) ;; C++文件(*.h *.cpp *.hpp)"));
         if(!file_name.isEmpty()){
             QFile file(file_name);
             if(!file.open(QIODevice::WriteOnly)){
                 QMessageBox::critical(this,tr("错误"),tr("不能打开文件"));
                 return;
             }
             QTextStream outs(&file);
             outs<<mini_text->toPlainText();
             outs.flush();
             file.close();
         }
     }
     else{
         QFile file(cur_file_name);
         if(!file.open(QIODevice::WriteOnly)){
             QMessageBox::critical(this,tr("错误"),tr("不能打开文件"));
             return;
         }
         QTextStream outs(&file);
         outs<<mini_text->toPlainText();
         outs.flush();
         file.close();
     }
 }

 void MainWindow::anotherSaveAct()
 {
     QString file_name = QFileDialog::getSaveFileName(this,tr("保存文件"),QString(),
                            tr("文本文件(*.txt) ;; C++文件(*.h *.cpp *.hpp)"));
     if(!file_name.isEmpty()){
         QFile file(file_name);
         if(!file.open(QIODevice::WriteOnly)){
             QMessageBox::critical(this,tr("错误"),tr("不能打开文件"));
             return;
         }
         QTextStream outs(&file);
         outs<<mini_text->toPlainText();
         outs.flush();
         file.close();
     }

 }

 void MainWindow::findReplace(QString find_str, bool flg)
 {
     bool find_flag;
     if(flg){
         find_flag = mini_text->find(find_str,QTextDocument::FindCaseSensitively);
     }
     else{
         find_flag = mini_text->find(find_str);
     }
     if(!find_flag){
         QMessageBox::information(this,tr("结果"),tr("没有找到查找内容"),QMessageBox::Yes);
     }
     else{
         find = true;
     }

 }

 void MainWindow::replaceCur(QString find_str, QString replace_str)
 {
     if(find){
         QTextCursor text_cursor = mini_text->textCursor();
         text_cursor.insertText(replace_str);
     }
     else{
         QMessageBox::information(this,tr("结果"),tr("没有内容不能替换")+find_str,QMessageBox::Yes);
     }
     find = false;
 }

 void MainWindow::replaceAll(QString find_str, QString replace_str,bool flg)
 {
     if(!flg){
         bool haf = mini_text->find(find_str);
         if(haf){
             QTextCursor text_cursor = mini_text->textCursor();
             text_cursor.insertText(replace_str);
             while(mini_text->find(find_str)){
                 text_cursor = mini_text->textCursor();
                 text_cursor.insertText(replace_str);
             }
             while(mini_text->find(find_str,QTextDocument::FindBackward)){
                 text_cursor = mini_text->textCursor();
                 text_cursor.insertText(replace_str);
             }
         }
         else{
              QMessageBox::information(this,tr("结果"),tr("没有内容不能替换 ")+find_str,QMessageBox::Yes);
         }
     }
     else{
         bool haf = mini_text->find(find_str,QTextDocument::FindCaseSensitively);
         if(haf){
             QTextCursor text_cursor = mini_text->textCursor();
             text_cursor.insertText(replace_str);
             while(mini_text->find(find_str,QTextDocument::FindCaseSensitively)){
                 text_cursor = mini_text->textCursor();
                 text_cursor.insertText(replace_str);
             }
             while(mini_text->find(find_str,QTextDocument::FindCaseSensitively|QTextDocument::FindBackward)){
                 text_cursor = mini_text->textCursor();
                 text_cursor.insertText(replace_str);
             }
         }
         else{
             QMessageBox::information(this,tr("结果"),tr("没有内容不能替换")+find_str,QMessageBox::Yes);
         }
     }

 }

 void MainWindow::printAct()
 {
     QPrinter printer;
     QString printer_name = printer.printerName();
        if( printer_name.size() == ){
            return;
        }
        QPrintDialog dlg(&printer, this);
        if (mini_text->textCursor().hasSelection()){
            dlg.addEnabledOption(QAbstractPrintDialog::PrintSelection);
        }
        if(dlg.exec() == QDialog::Accepted){
            mini_text->print(&printer);
        }
 }

 void MainWindow::findAct(QString str,bool ignore,bool choose)
 {
     QString text = str;
     bool find_flag;
     if(!text.isEmpty()){
         if(choose){
             if(ignore){
               find_flag = mini_text->find(text,QTextDocument::FindCaseSensitively);
             }
             else{
                 find_flag = mini_text->find(text);

             }
         }
         else{
             if(ignore){
                 find_flag = mini_text->find(text,QTextDocument::FindBackward|QTextDocument::FindCaseSensitively);
             }
             else{
                 find_flag = mini_text->find(text,QTextDocument::FindBackward);

             }
         }
         if(!find_flag){
             QMessageBox::information(this,tr("结果"),tr("没有找到查找内容"),QMessageBox::Yes);
         }
     }

 }

 void MainWindow::aboutAct()
 {
     QMessageBox message(QMessageBox::NoIcon,tr("关于"), tr("version: v1.0\n"
                                                           "author: karllen\n"
                                                           "qq: 1160113606\n"
                                                          "Begin Learning The Qt"));
     message.setIconPixmap(QPixmap(tr(":/images/me")));
     message.exec();

 }

 void MainWindow::showFindDialog()
 {
     find_dialog->show();
 }

 void MainWindow::showReplaceDialog()
 {
     replace_dialog->show();
 }

 void MainWindow::exitAct()
 {
     this->close();

 }

查找对话框类：

 #ifndef FINDDIALOG_H
 #define FINDDIALOG_H
 #include <QDialog>
 #include <QLineEdit>
 #include <QLabel>
 #include <QPushButton>
 #include <QRadioButton>
 #include <QGridLayout>
 #include <QHBoxLayout>
 #include <QGroupBox>
 #include <QCheckBox>

 class FindDialog:public QDialog
 {
     Q_OBJECT
 public:
     FindDialog(QWidget *parent = );
     ~FindDialog();

 signals:
     void findTextDataButtonClickedSignal(QString,bool,bool);

 private slots:
     void findButtonState();
     void findDataButtonClickedState();

 private:
     QLineEdit *find_edit;
     QLabel    *find_label,*ignore_label,*next_label,*back_label;
     QPushButton *find_button;
     QRadioButton *next_radio;
     QRadioButton *back_radio;
     QCheckBox *ignore_flag;
 };

 #endif // FINDDIALOG_H

 #include "finddialog.h"

 FindDialog::FindDialog(QWidget *parent)
     :QDialog(parent)
 {
     setWindowTitle(tr("查找"));
     find_label = new QLabel(tr("查找"));
     ignore_label = new QLabel(tr("区分大小写"));
     next_label = new QLabel(tr("向后"));
     back_label = new QLabel(tr("向前"));
     find_edit = new QLineEdit;
     find_button = new QPushButton(tr("查找下一个"));
     next_radio = new QRadioButton;
     back_radio = new QRadioButton;
     ignore_flag = new QCheckBox;

     find_edit->setText(tr(""));

     QGridLayout *grid_layout = new QGridLayout(this);
     grid_layout->addWidget(find_label,,);
     grid_layout->addWidget(find_edit,,);
     grid_layout->addWidget(find_button,,);

     QHBoxLayout *ignore_layout = new QHBoxLayout;
     ignore_layout->setSpacing();
     ignore_layout->addWidget(ignore_label);
     ignore_layout->addWidget(ignore_flag);

     QHBoxLayout *radio_layout = new QHBoxLayout;
     radio_layout->addWidget(next_label);
     radio_layout->addWidget(next_radio);

     radio_layout->addWidget(back_label);
     radio_layout->addWidget(back_radio);

     QGroupBox *group_radio = new QGroupBox(tr("方向"),this);
     group_radio->setLayout(radio_layout);

     QHBoxLayout *do_radio = new QHBoxLayout;
     do_radio->addWidget(group_radio);

     grid_layout->addLayout(ignore_layout,,);
     grid_layout->addLayout(do_radio,,);

     this->setMaximumSize(,);
     next_radio->setChecked(true);
     find_button->setEnabled(false);
     connect(find_edit,SIGNAL(textChanged(QString)),this,SLOT(findButtonState()));
     connect(find_button,SIGNAL(clicked(bool)),this,SLOT(findDataButtonClickedState()));
 }

 FindDialog::~FindDialog()
 {
     if(find_edit){
         delete find_edit;
     }
     if(find_label){
         delete find_label;
     }
     if(ignore_label){
         delete ignore_label;
     }
     if(next_label){
         delete next_label;
     }
     if(back_label){
         delete back_label;
     }
     if(find_button){
         delete find_button;
     }
     if(next_radio){
         delete next_radio;
     }
     if(back_radio){
         delete back_radio;
     }
     if(ignore_flag){
         delete ignore_flag;
     }
 }

 void FindDialog::findButtonState()
 {
     if(find_edit->text().isEmpty()){
         find_button->setEnabled(false);
     }
     else{
         find_button->setEnabled(true);
     }

 }

 void FindDialog::findDataButtonClickedState()
 {
     if(find_edit->text().isEmpty()){
         return;
     }
     QString str = find_edit->text();
     if(next_radio->isChecked()){
         if(ignore_flag->isChecked()){
             emit findTextDataButtonClickedSignal(str,true,true);
         }
         else{
             emit findTextDataButtonClickedSignal(str,false,true);
         }
     }
     if(back_radio->isChecked()){
         if(ignore_flag->isChecked()){
             emit findTextDataButtonClickedSignal(str,true,false);
         }
         else{
             emit findTextDataButtonClickedSignal(str,false,false);
         }
     }
 }

替换对话框类:

 #ifndef REPLACEDIALOG_H
 #define REPLACEDIALOG_H

 #include <QDialog>
 #include <QPushButton>
 #include <QLabel>
 #include <QCheckBox>
 #include <QLineEdit>
 #include <QGridLayout>
 #include <QVBoxLayout>

 class ReplaceDialog:public QDialog
 {
     Q_OBJECT
 public:
     ReplaceDialog(QWidget *parent = );
     ~ReplaceDialog();
 signals:
     void replaceAllStr(QString , QString,bool);
     void replaceCurOneStr(QString,QString);
     void findReplaceStr(QString,bool);
 private slots:
     void chooseStrSlot();
     void findButtonStateSlot();
     void replaceOneButtonStateSlot();
     void replaceAllButtonStateSlot();
 private:
     QLineEdit *find_str;
     QLineEdit *replace_str;
     QPushButton *find_next_button;
     QPushButton *replaced_one_button;
     QPushButton *replaced_all_button;
     QPushButton *cancle_button;
     QCheckBox *ignore_flag;
     QLabel  *find_label;
     QLabel  *replace_label;
 };

 #endif // REPLACEDIALOG_H

 #include "replacedialog.h"

 ReplaceDialog::ReplaceDialog(QWidget *parent)
     :QDialog(parent)
 {
     find_label          = new QLabel(tr("查找内容"));
     replace_label       = new QLabel(tr("替换为"));
     find_str            = new QLineEdit();
     replace_str         = new QLineEdit();
     find_next_button    = new QPushButton(tr("查找下一个"));
     replaced_one_button = new QPushButton(tr("替换"));
     replaced_all_button = new QPushButton(tr("全部替换"));
     cancle_button       = new QPushButton(tr("取消"));
     ignore_flag         = new QCheckBox(tr("区分大小写"));

     QGridLayout *grdly  = new QGridLayout(this);
     QVBoxLayout *vboxly = new QVBoxLayout(this);

     vboxly->addWidget(replaced_all_button);
     vboxly->addWidget(cancle_button);
     grdly->addWidget(find_label,,);
     grdly->addWidget(find_str,,);
     grdly->addWidget(find_next_button,,);
     grdly->addWidget(replace_label,,);
     grdly->addWidget(replace_str,,);
     grdly->addWidget(replaced_one_button,,);
     grdly->addWidget(ignore_flag,,);
     grdly->addLayout(vboxly,,);

     find_str->setText(tr(""));
     replace_str->setText(tr(""));
     find_next_button->setEnabled(false);
     replaced_one_button->setEnabled(false);
     replaced_all_button->setEnabled(false);

     this->setMaximumSize(,);

     connect(find_str,SIGNAL(textChanged(QString)),this,SLOT(chooseStrSlot()));
     connect(cancle_button,SIGNAL(clicked()),this,SLOT(close()));
     connect(find_next_button,SIGNAL(clicked()),this,SLOT(findButtonStateSlot()));
     connect(replaced_one_button,SIGNAL(clicked()),this,SLOT(replaceOneButtonStateSlot()));
     connect(replaced_all_button,SIGNAL(clicked()),this,SLOT(replaceAllButtonStateSlot()));
 }

 ReplaceDialog::~ReplaceDialog()
 {
     if(find_str){
         delete find_str;
     }
     if(replace_str){
         delete replace_str;
     }
     if(find_next_button){
         delete find_next_button;
     }
     if(replaced_one_button){
         delete replaced_one_button;
     }
     if(replaced_all_button){
         delete replaced_all_button;
     }
     if(cancle_button){
         delete cancle_button;
     }
     if(ignore_flag){
         delete ignore_flag;
     }
     if(find_label){
         delete find_label;
     }
     if(replace_label){
         delete replace_label;
     }
 }

 void ReplaceDialog::chooseStrSlot()
 {
     if(!find_str->text().isEmpty()){
         find_next_button->setEnabled(true);
         replaced_one_button->setEnabled(true);
         replaced_all_button->setEnabled(true);
     }
     else{
         find_next_button->setEnabled(false);
         replaced_one_button->setEnabled(false);
         replaced_all_button->setEnabled(false);
     }
 }

 void ReplaceDialog::findButtonStateSlot()
 {
     if(ignore_flag->isChecked()){
         emit findReplaceStr(find_str->text(),true);
     }
     else{
         emit findReplaceStr(find_str->text(),false);
     }
 }

 void ReplaceDialog::replaceOneButtonStateSlot()
 {
     emit replaceCurOneStr(find_str->text(),replace_str->text());

 }

 void ReplaceDialog::replaceAllButtonStateSlot()
 {
     if(ignore_flag->isChecked()){
         emit replaceAllStr(find_str->text() , replace_str->text(),true);
     }
     else{
         emit replaceAllStr(find_str->text() , replace_str->text(),false);
     }

 }

main函数：

 #include "mainwindow.h"
 #include "finddialog.h"
 #include <QApplication>

 int main(int argc, char *argv[])
 {
     QApplication a(argc, argv);

     MainWindow w;
     w.show();
     return a.exec();
 }

注：代码下载地址 http://download.csdn.net/detail/u010085340/9289609