QT 创建主窗口 MainWindow 实例

1.

2. mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QWorkspace>
#include <QMdiArea>
#include <QMdiSubWindow>

class QAction;
class QMenu;
class QToolBar;
class QTextEdit;

class MainWindow : public QMainWindow
{
    Q_OBJECT
public:
    MainWindow();

    void createMenus();
    void createActions();
    void createToolBars();
    void loadFile(QString fileName);

public slots:
    void slotNewFile();
    void slotOpenFile();
    void slotSaveFile();
    void slotCopy();
    void slotCut();
    void slotPaste();
    void slotAbout();

protected:
    //void closeEvent(QCloseEvent *);

private:
    QTextCodec *codec;
    QMenu *fileMenu;
    QMenu *editMenu;
    QMenu *aboutMenu;
    QToolBar *fileTool;
    QToolBar *editTool;
    QAction *fileOpenAction;
    QAction *fileNewAction;
    QAction *fileSaveAction;
    QAction *exitAction;
    QAction *copyAction;
    QAction *cutAction;
    QAction *pasteAction;
    QAction *aboutAction;

    QTextEdit * text;

    QWorkspace *workSpace;
};

#endif // MAINWINDOW_H

3. mainwindow.cpp

MainWindow构造函数中可加入 setAttribute(Qt::WA_DeleteOnClose);

多窗口时关闭窗口默认是隐藏，这样设置后为关闭，防止内存泄露。

#include "mainwindow.h"

#include <QtGui>

// 翋敦諳妗珋
MainWindow::MainWindow()
{
    setWindowTitle(tr("myMainWindow"));
    text = new QTextEdit(this);
    setCentralWidget(text);

/*    workSpace = new QWorkspace;
    setCentralWidget(workSpace);
    QMainWindow *window1 = new QMainWindow;
    window1->setWindowTitle("window1");
    QTextEdit *text1 = new QTextEdit;
    text1->setText("text1");
    window1->setCentralWidget(text1);
    workSpace->addWindow(window1);
*/
    createActions();
    createMenus();
    createToolBars();
}

void
MainWindow::createActions()
{

    // file open action
    fileOpenAction = new QAction(QIcon(":/images/open.png"),tr("Open"),this);	// 湖羲恅璃
    fileOpenAction->setShortcut(tr("Ctrl+O"));
    fileOpenAction->setStatusTip(tr("open a file"));
    connect(fileOpenAction,SIGNAL(triggered()),this,SLOT(slotOpenFile()));

    // file new action
    fileNewAction = new QAction(QIcon(":/images/new.png"),tr("New"),this);	// 陔膘恅璃
    fileNewAction->setShortcut(tr("Ctrl+N"));
    fileNewAction->setStatusTip(tr("new file"));
    connect(fileNewAction,SIGNAL(triggered()),this,SLOT(slotNewFile()));

    // save file action
    fileSaveAction = new QAction(QPixmap(":/images/save.png"),tr("Save"),this);	// 悵湔恅璃
    fileSaveAction->setShortcut(tr("Ctrl+S"));
    fileSaveAction->setStatusTip(tr("save file"));
    connect(fileSaveAction,SIGNAL(activated()),this,SLOT(slotSaveFile()));

    // exit action
    exitAction = new QAction(tr("Exit"), this);	// 豖堤
    exitAction->setShortcut(tr("Ctrl+Q"));
    exitAction->setStatusTip(tr("exit"));
    connect(exitAction, SIGNAL(triggered()), this, SLOT(close()));

    cutAction = new QAction(QIcon(":/images/cut.png"), tr("Cut"), this);		// 熟
    cutAction->setShortcut(tr("Ctrl+X"));
    cutAction->setStatusTip(tr("cut to clipboard"));
    connect(cutAction, SIGNAL(triggered()), text, SLOT(cut()));

    copyAction = new QAction(QIcon(":/images/copy.png"), tr("Copy"), this);		// 葩秶
    copyAction->setShortcut(tr("Ctrl+C"));
    copyAction->setStatusTip(tr("copy to clipboard"));
    connect(copyAction, SIGNAL(triggered()), text, SLOT(copy()));

    pasteAction = new QAction(QIcon(":/images/paste.png"), tr("Paste"), this);		// 梜泂
    pasteAction->setShortcut(tr("Ctrl+V"));
    pasteAction->setStatusTip(tr("paste clipboard to selection"));
    connect(pasteAction, SIGNAL(triggered()), text, SLOT(paste()));

    aboutAction = new QAction(tr("About"), this);		// 壽衾
    connect(aboutAction, SIGNAL(triggered()), this, SLOT(slotAbout()));
}

void
MainWindow::createMenus()
{
    fileMenu = menuBar()->addMenu(tr("File"));
    editMenu = menuBar()->addMenu(tr("Edit"));
    aboutMenu = menuBar()->addMenu(tr("Help"));

    fileMenu->addAction(fileNewAction);
    fileMenu->addAction(fileOpenAction);
    fileMenu->addAction(fileSaveAction);
    fileMenu->addAction(exitAction);

    editMenu->addAction(copyAction);
    editMenu->addAction(cutAction);
    editMenu->addAction(pasteAction);

    aboutMenu->addAction(aboutAction);
}

void
MainWindow::createToolBars()
{

    fileTool = addToolBar(tr("File"));
    fileTool->setMovable(false);
    editTool = addToolBar(tr("Edit"));

    fileTool->addAction(fileNewAction);
    fileTool->addAction(fileOpenAction);
    fileTool->addAction(fileSaveAction);

    editTool->addAction(copyAction);
    editTool->addAction(cutAction);
    editTool->addAction(pasteAction);

}

void MainWindow::slotNewFile()
{
    MainWindow *newWin = new MainWindow();
    newWin->show();
}

void MainWindow::loadFile(QString fileName)
{
    QFile file( fileName );
    if ( file.open (QIODevice::ReadOnly | QIODevice::Text))
    {
        QTextStream textStream( &file );
        while( !textStream.atEnd() )
        {
            text->append( textStream.readLine() );
        }
    }
}

void MainWindow::slotOpenFile()
{
    QString fileName = QFileDialog::getOpenFileName(this);
    if ( !fileName.isEmpty() )
    {
        if( text->document()->isEmpty() )
            loadFile(fileName);
        else
        {
            MainWindow *newWin = new MainWindow;
            newWin->show();
            newWin->loadFile(fileName);
        }
    }
}

void MainWindow::slotSaveFile()
{
}

void MainWindow::slotCopy()
{
}

void MainWindow::slotCut()
{
}

void MainWindow::slotPaste()
{
}

void MainWindow::slotAbout()
{
}