4.11 实例：标准菜单使用方法.txt

来自「qt的源代码」· 文本 代码 · 共 327 行

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
class QAction;
class QActionGroup;
class QLabel;
class QMenu;
class MainWindow : public QMainWindow
{
    Q_OBJECT
public:
    MainWindow();
protected:
    void contextMenuEvent(QContextMenuEvent *event);
private slots:
void newFile();
    void open();
    void save();
    void print();
    void undo();
    void redo();
    void cut();
    void copy();
    void paste();
    void bold();
    void italic();
    void leftAlign();
    void rightAlign();
    void justify();
    void center();
    void setLineSpacing();
    void setParagraphSpacing();
    void about();
 void aboutQt();
private:
    void createActions();
    void createMenus();
    QMenu *fileMenu;
    QMenu *editMenu;
    QMenu *formatMenu;
    QMenu *helpMenu;
    QActionGroup *alignmentGroup;
    QAction *newAct;
    QAction *openAct;
    QAction *saveAct;
    QAction *printAct;
    QAction *exitAct;
    QAction *undoAct;
    QAction *redoAct;
    QAction *cutAct;
    QAction *copyAct;
    QAction *pasteAct;
    QAction *boldAct;
    QAction *italicAct;
    QAction *leftAlignAct;
    QAction *rightAlignAct;
    QAction *justifyAct;
    QAction *centerAct;
    QAction *setLineSpacingAct;
    QAction *setParagraphSpacingAct;
    QAction *aboutAct;
    QAction *aboutQtAct;
    QLabel *infoLabel;
};
#endif
#include <QtGui>
#include "mainwindow.h"
MainWindow::MainWindow()
{
QWidget *widget = new QWidget;
    setCentralWidget(widget);
    QWidget *topFiller = new QWidget;
    topFiller->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
    infoLabel = new QLabel(tr("<i>Choose a menu option, or right-click to "
                              "invoke a context menu</i>"));
infoLabel->setFrameStyle(QFrame::StyledPanel | QFrame::Sunken);
infoLabel->setAlignment(Qt::AlignCenter);
QWidget *bottomFiller = new QWidget;
    bottomFiller->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
    QVBoxLayout *layout = new QVBoxLayout;
    layout->setMargin(5);
    layout->addWidget(topFiller);
    layout->addWidget(infoLabel);
    layout->addWidget(bottomFiller);
    widget->setLayout(layout);
    createActions();
    createMenus();
    QString message = tr("A context menu is available by right-clicking");
    statusBar()->showMessage(message);
    setWindowTitle(tr("Menus"));
setMinimumSize(160,160);
resize(480,320);
}
void MainWindow::contextMenuEvent(QContextMenuEvent *event)
{
    QMenu menu(this);
    menu.addAction(cutAct);
    menu.addAction(copyAct);
    menu.addAction(pasteAct);
    menu.exec(event->globalPos());
}
void MainWindow::newFile()  
{
    infoLabel->setText(tr("Invoked <b>File|New</b>"));
}
void MainWindow::open() 
{
    infoLabel->setText(tr("Invoked <b>File|Open</b>"));
}
void MainWindow::save()
{
    infoLabel->setText(tr("Invoked <b>File|Save</b>"));
}
void MainWindow::print( ) 
{
    infoLabel->setText(tr("Invoked <b>File|Print</b>"));
}
void MainWindow::undo() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Undo</b>"));
}
void MainWindow::redo() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Redo</b>"));
}
void MainWindow::cut()
{
    infoLabel->setText(tr("Invoked <b>Edit|Cut</b>"));
}
void MainWindow::copy() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Copy</b>"));
}
void MainWindow::paste() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Paste</b>"));
}
void MainWindow::bold() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Bold</b>"));
}
void MainWindow::italic()
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Italic</b>"));
}
void MainWindow::leftAlign() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Left Align</b>"));
}
void MainWindow::rightAlign() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Right Align</b>"));
}
void MainWindow::justify() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Justify</b>"));
}
void MainWindow::center()
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Center</b>"));
}
void MainWindow::setLineSpacing() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Set Line Spacing</b>"));
}
void MainWindow::setParagraphSpacing() 
{
    infoLabel->setText(tr("Invoked <b>Edit|Format|Set Paragraph Spacing</b>"));
}
void MainWindow::about() 
{
    infoLabel->setText(tr("Invoked <b>Help|About</b>"));
    QMessageBox::about(this, tr("About Menu"),
            tr("The <b>Menu</b> example shows how to create "
               "menu-bar menus and context menus."));
}
void MainWindow::aboutQt() 
{
    infoLabel->setText(tr("Invoked <b>Help|About Qt</b>"));
}
void MainWindow::createActions()
{
    newAct = new QAction(tr("&New"), this);
    newAct->setShortcut(tr("Ctrl+N"));
    newAct->setStatusTip(tr("Create a new file"));
connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));

下面我们举一个例子来看怎样使用createActions()函数才能方便地建立各种的actions
openAct = new QAction(tr("&Open..."), this);
    openAct->setShortcut(tr("Ctrl+O"));
    openAct->setStatusTip(tr("Open an existing file"));
    connect(openAct, SIGNAL(triggered()), this, SLOT(open()));
    saveAct = new QAction(tr("&Save"), this);
    saveAct->setShortcut(tr("Ctrl+S"));
    saveAct->setStatusTip(tr("Save the document to disk"));
    connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));
    printAct = new QAction(tr("&Print..."), this);
    printAct->setShortcut(tr("Ctrl+P"));
    printAct->setStatusTip(tr("Print the document"));
    connect(printAct, SIGNAL(triggered()), this, SLOT(print()));
    exitAct = new QAction(tr("E&xit"), this);
    exitAct->setShortcut(tr("Ctrl+Q"));
    exitAct->setStatusTip(tr("Exit the application"));
    connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));
    undoAct = new QAction(tr("&Undo"), this);
    undoAct->setShortcut(tr("Ctrl+Z"));
    undoAct->setStatusTip(tr("Undo the last operation"));
    connect(undoAct, SIGNAL(triggered()), this, SLOT(undo()));
    redoAct = new QAction(tr("&Redo"), this);
    redoAct->setShortcut(tr("Ctrl+Y"));
    redoAct->setStatusTip(tr("Redo the last operation"));
    connect(redoAct, SIGNAL(triggered()), this, SLOT(redo()));
    cutAct = new QAction(tr("Cu&t"), this);
    cutAct->setShortcut(tr("Ctrl+X"));
    cutAct->setStatusTip(tr("Cut the current selection's contents to the ""clipboard"));
    connect(cutAct, SIGNAL(triggered()), this, SLOT(cut()));
    copyAct = new QAction(tr("&Copy"), this);
    copyAct->setShortcut(tr("Ctrl+C"));
    copyAct->setStatusTip(tr("Copy the current selection's contents to the "clipboard"));
    connect(copyAct, SIGNAL(triggered()), this, SLOT(copy()));
    pasteAct = new QAction(tr("&Paste"), this);
    pasteAct->setShortcut(tr("Ctrl+V"));
    pasteAct->setStatusTip(tr("Paste the clipboard's contents into the current "
                              "selection"));
    connect(pasteAct, SIGNAL(triggered()), this, SLOT(paste()));
    boldAct = new QAction(tr("&Bold"), this);
    boldAct->setCheckable(true);
    boldAct->setShortcut(tr("Ctrl+B"));
    boldAct->setStatusTip(tr("Make the text bold"));
    connect(boldAct, SIGNAL(triggered()), this, SLOT(bold()));
    QFont boldFont = boldAct->font();
    boldFont.setBold(true);
    boldAct->setFont(boldFont);
    italicAct = new QAction(tr("&Italic"), this);
    italicAct->setCheckable(true);
    italicAct->setShortcut(tr("Ctrl+I"));
    italicAct->setStatusTip(tr("Make the text italic"));
    connect(italicAct, SIGNAL(triggered()), this, SLOT(italic()));
    QFont italicFont = italicAct->font();
    italicFont.setItalic(true);
    italicAct->setFont(italicFont);
    setLineSpacingAct = new QAction(tr("Set &Line Spacing..."), this);
    setLineSpacingAct->setStatusTip(tr("Change the gap between the lines of a "
                                       "paragraph"));
    connect(setLineSpacingAct, SIGNAL(triggered()), this, SLOT(setLineSpacing()));
    setParagraphSpacingAct = new QAction(tr("Set &Paragraph Spacing..."), this);
    setLineSpacingAct->setStatusTip(tr("Change the gap between paragraphs"));
    connect(setParagraphSpacingAct, SIGNAL(triggered()),
            this, SLOT(setParagraphSpacing()));
    aboutAct = new QAction(tr("&About"), this);
    aboutAct->setStatusTip(tr("Show the application's About box"));
    connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
    aboutQtAct = new QAction(tr("About &Qt"), this);
    aboutQtAct->setStatusTip(tr("Show the Qt library's About box"));
    connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
    connect(aboutQtAct, SIGNAL(triggered()), this, SLOT(aboutQt()));
    leftAlignAct = new QAction(tr("&Left Align"), this);
    leftAlignAct->setCheckable(true);
    leftAlignAct->setShortcut(tr("Ctrl+L"));
    leftAlignAct->setStatusTip(tr("Left align the selected text"));
    connect(leftAlignAct, SIGNAL(triggered()), this, SLOT(leftAlign()));
    rightAlignAct = new QAction(tr("&Right Align"), this);
    rightAlignAct->setCheckable(true);
    rightAlignAct->setShortcut(tr("Ctrl+R"));
    rightAlignAct->setStatusTip(tr("Right align the selected text"));
    connect(rightAlignAct, SIGNAL(triggered()), this, SLOT(rightAlign()));
    justifyAct = new QAction(tr("&Justify"), this);
    justifyAct->setCheckable(true);
    justifyAct->setShortcut(tr("Ctrl+J"));
    justifyAct->setStatusTip(tr("Justify the selected text"));
    connect(justifyAct, SIGNAL(triggered()), this, SLOT(justify()));
    centerAct = new QAction(tr("&Center"), this);
    centerAct->setCheckable(true);
    centerAct->setShortcut(tr("Ctrl+E"));
    centerAct->setStatusTip(tr("Center the selected text"));
    connect(centerAct, SIGNAL(triggered()), this, SLOT(center()));
    alignmentGroup = new QActionGroup(this);
    alignmentGroup->addAction(leftAlignAct);
    alignmentGroup->addAction(rightAlignAct);
    alignmentGroup->addAction(justifyAct);
    alignmentGroup->addAction(centerAct);
leftAlignAct->setChecked(true);
}
void MainWindow::createMenus()
{
    fileMenu = menuBar()->addMenu(tr("&File"));
    fileMenu->addAction(newAct);
    fileMenu->addAction(openAct);
    fileMenu->addAction(saveAct);
    fileMenu->addAction(printAct);
    fileMenu->addSeparator();
    fileMenu->addAction(exitAct);
    editMenu = menuBar()->addMenu(tr("&Edit"));
    editMenu->addAction(undoAct);
    editMenu->addAction(redoAct);
    editMenu->addSeparator();
    editMenu->addAction(cutAct);
    editMenu->addAction(copyAct);
    editMenu->addAction(pasteAct);
    editMenu->addSeparator();
    helpMenu = menuBar()->addMenu(tr("&Help"));
    helpMenu->addAction(aboutAct);
    helpMenu->addAction(aboutQtAct);
    formatMenu = editMenu->addMenu(tr("&Format"));
    formatMenu->addAction(boldAct);
    formatMenu->addAction(italicAct);
    formatMenu->addSeparator()->setText(tr("Alignment"));
    formatMenu->addAction(leftAlignAct);
    formatMenu->addAction(rightAlignAct);
    formatMenu->addAction(justifyAct);
    formatMenu->addAction(centerAct);
    formatMenu->addSeparator();
    formatMenu->addAction(setLineSpacingAct);
formatMenu->addAction(setParagraphSpacingAct);
}
{
#include <QApplication>
#include "mainwindow.h"
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    MainWindow window;
    window.show();
    return app.exec();
}
}