qt編程實現的簡易記事本(範例)

     Qt是一種跨平台的原生開發架構，面向所有主要的作業系統，包括Linux、Windows、Mac、Symbian和Maemo。本文介紹的是在Windows下用qt編程實現的簡易記事本，有興趣學習qt編程的可以看看。本人也是剛接觸qt編程，覺得qt相對其他語言來說學起來還是比較容易的。   這是我用Qt Creator實現的簡易記事本：QQ迷你版 本網聊天軟體詳見Qt編程—我的QQ(區域網路可用)—含原始碼 上面介面是用Qt  Designer實現的 是不是在actionNew（建立）前面有出現小表徵圖，在往工具列裡移動，就出現上述效果了。           這隻是實現了一部分功能，大家可以看一下 mainwindow.h檔案

<span style="font-size:14px;">#ifndef MAINWINDOW_H#define MAINWINDOW_H#include <QMainWindow>#include <QFileDialog>#include <QTextStream>#include <QMessageBox>#include <QDialog>#include <QLineEdit>#include <QPushButton>#include <QVBoxLayout>#include <QHBoxLayout>namespace Ui {    class MainWindow;}class MainWindow : public QMainWindow{    Q_OBJECTpublic:    explicit MainWindow(QWidget *parent = 0);    ~MainWindow();    void changeTitle(const QString &filename);    void openfile(const QString &filename);    void savefile(const QString &filename);private:    Ui::MainWindow *ui;    QString curFile;    QLineEdit *find_textLineEdit;private slots:    void show_findText();    void on_action_2_triggered();//尋找    void on_plan_textEdit_copyAvailable(bool b);    void on_plan_textEdit_textChanged();    void on_action_U_triggered();//撤銷    void on_action_P_triggered();//粘貼    void on_action_C_triggered();//複製    void on_action_T_triggered();//剪下    void on_actionExit_triggered();//退出    bool on_actionSave_triggered();//儲存    bool on_actionSave_As_triggered();//另存新檔    void on_actionOpen_triggered();//開啟    void on_actionNew_triggered();//建立};#endif // MAINWINDOW_H</span>

main.h檔案

<span style="font-size:14px;">#include <QtGui/QApplication>#include <QTextCodec>#include "mainwindow.h"int main(int argc, char *argv[]){    QApplication a(argc, argv);    QTextCodec::setCodecForCStrings(QTextCodec::codecForName("GB2312"));    QTextCodec::setCodecForLocale(QTextCodec::codecForName("GB2312"));    QTextCodec::setCodecForTr(QTextCodec::codecForName("GB2312"));    MainWindow w;    w.show();    return a.exec();}</span>

mainwindow.cpp

<span style="font-size:14px;">#include "mainwindow.h"#include "ui_mainwindow.h"#include<QDebug>MainWindow::MainWindow(QWidget *parent) :    QMainWindow(parent),    ui(new Ui::MainWindow){    ui->setupUi(this);    this->changeTitle("");    this->setCentralWidget(ui->plan_textEdit);    //設定action的屬性    ui->action_T->setEnabled(false);    ui->action_C->setEnabled(false);    //設定介面表徵圖  this->setWindowIcon(QIcon(":/images/editor.png"));}MainWindow::~MainWindow(){    delete ui;}void MainWindow::savefile(const QString &filename){    QFile file(filename);    if(!file.open(QIODevice::WriteOnly | QIODevice::Text)){        QMessageBox::warning(this, "Save",                             tr("Save , error ?")                             .arg(filename)                            .arg(file.errorString()));        return ;    }    QTextStream out(&file);    out << ui->plan_textEdit->toPlainText();    file.close();}void MainWindow::openfile(const QString &filename){    QFile file(filename);    if(file.open(QIODevice::ReadOnly | QIODevice::Text)){        QMessageBox::warning(this, "Open",                             tr("Save , error ?")                             .arg(filename)                             .arg(file.errorString()));        return ;    }    QTextStream in(&file);    QString s=in.readAll();    ui->plan_textEdit->setPlainText(s);}void MainWindow::changeTitle(const QString &filename){    qDebug()<<"***"<<filename;    if(filename.isEmpty()){         this->curFile = "";         this->setWindowTitle(tr("無標題.txt[*]--記事本"));    }    else{        this->curFile = filename;        QFileInfo fi(filename);        QString name=fi.fileName();        this->setWindowTitle(tr("%1[*]--記事本").arg(name));        qDebug()<<"===="<<name;    }    this->setWindowModified(false);    ui->plan_textEdit->document()->setModified(false);}void MainWindow::on_actionNew_triggered()//建立{    QTextDocument *document=ui->plan_textEdit->document();    if(!document->isModified()){        ui->plan_textEdit->setPlainText("");        this->changeTitle("");        return ;    }    int ret=QMessageBox::question(this, "Save?",                                  "disSave, Save",                                  QMessageBox::Save | QMessageBox::Discard | QMessageBox::Cancel);    switch(ret)    {    case QMessageBox::Cancel:        break;    case QMessageBox::Discard:        ui->plan_textEdit->setPlainText("");        this->changeTitle("");        break;    case QMessageBox::Save:          if(!on_actionSave_triggered())                 return ;          ui->plan_textEdit->setPlainText("");          this->changeTitle("");          break;         }}void MainWindow::on_actionOpen_triggered()//開啟{    QTextDocument *document=ui->plan_textEdit->document();    if(document->isModified()){        int ret=QMessageBox::question(this, "Save?",                                      "disSave, Save",                                      QMessageBox::Save | QMessageBox::Discard | QMessageBox::Cancel);        if(ret==QMessageBox::Cancel){            return ;        }        else if(ret==QMessageBox::Save){        }    }    //沒修改    正常儲存    放棄儲存    QString filename=QFileDialog::getOpenFileName(this);    if(filename.isEmpty())        return ;    this->openfile(filename);    this->changeTitle(filename);}bool MainWindow::on_actionSave_As_triggered()//另存新檔{    QString fileName=QFileDialog::getSaveFileName(this,tr("Save File"));    if(fileName.isEmpty())        return false;    this->savefile(fileName);    this->changeTitle(fileName);    return true;}bool MainWindow::on_actionSave_triggered()//儲存{    if(this->curFile.isEmpty())     // qDebug()<<"+++";            return on_actionSave_As_triggered();    else    {        savefile(this->curFile);      this->setWindowModified(false);    }    return true;}void MainWindow::on_actionExit_triggered()//退出{    this->close();}void MainWindow::on_action_T_triggered()//剪下{    this->ui->plan_textEdit->cut();}void MainWindow::on_action_C_triggered()//複製{    this->ui->plan_textEdit->copy();}void MainWindow::on_action_P_triggered()//粘貼{    this->ui->plan_textEdit->paste();}void MainWindow::on_action_U_triggered()//撤銷{   this->ui->plan_textEdit->undo();}void MainWindow::on_plan_textEdit_textChanged(){    //qDebug()<<"niaho";    this->setWindowModified(true);}void MainWindow::on_plan_textEdit_copyAvailable(bool b){    ui->action_T->setEnabled(b);    ui->action_C->setEnabled(b);}//這部分是編碼實現的，可以看看與介面設計實現的有什麼不一樣void MainWindow::on_action_2_triggered()//尋找{   QDialog *findDlg=new QDialog(this);   findDlg->setWindowTitle(tr("Find!"));   find_textLineEdit=new QLineEdit(findDlg);   QPushButton *find_Bth=new QPushButton(tr("尋找下一個"),findDlg);   QHBoxLayout *layout=new QHBoxLayout(findDlg);   layout->addWidget(find_textLineEdit);   layout->addWidget(find_Bth);   findDlg->show();   connect(find_Bth,SIGNAL(clicked()),this,SLOT(show_findText()));}void MainWindow::show_findText(){    QString findText=find_textLineEdit->text();    if(!ui->plan_textEdit->find(findText,QTextDocument::FindBackward))    {        QMessageBox::warning(this,tr("尋找"),tr("找不到 %1").arg(findText));    }}</span>

其實還有一部分功能沒實現，有興趣的話可以關注我下一篇文章。