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 = 0);
    ~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(900,500);
    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() == 0){
           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
"
                                                          "author: karllen
"
                                                          "qq: 1160113606
"
                                                         "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 = 0);
    ~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,0,0);
    grid_layout->addWidget(find_edit,0,1);
    grid_layout->addWidget(find_button,0,3);

    QHBoxLayout *ignore_layout = new QHBoxLayout;
    ignore_layout->setSpacing(10);
    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,1,0);
    grid_layout->addLayout(do_radio,1,1);

    this->setMaximumSize(300,100);
    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 = 0);
    ~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,0,0);
    grdly->addWidget(find_str,0,1);
    grdly->addWidget(find_next_button,0,2);
    grdly->addWidget(replace_label,1,0);
    grdly->addWidget(replace_str,1,1);
    grdly->addWidget(replaced_one_button,1,2);
    grdly->addWidget(ignore_flag,2,1);
    grdly->addLayout(vboxly,2,2);

    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(300,100);

    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