创建主窗口

1：QMainWindow中的区域分配

2：创建菜单和工具栏包括以下这些步骤

　　创建并且设置动作

　　创建菜单并且把动作添加到菜单上

　　创建工具栏并且把动作添加到工具栏上

 

qt通过“动作”，即action来简化有关菜单和工具栏的编程，动作有一个加速键，一个父对象，一个图标，一个快捷键，一个状态提示

void MainWindow::createActions()
{
    newAction = new QAction(tr("&New"), this);
    newAction->setIcon(QIcon(":/images/new.png"));
    newAction->setShortcut(QKeySequence::New);
    newAction->setStatusTip(tr("Create a new spreadsheet file"));
    connect(newAction, SIGNAL(triggered()), this, SLOT(newFile()));

    openAction = new QAction(tr("&Open..."), this);
    openAction->setIcon(QIcon(":/images/open.png"));
    openAction->setShortcut(QKeySequence::Open);
    openAction->setStatusTip(tr("Open an existing spreadsheet file"));
    connect(openAction, SIGNAL(triggered()), this, SLOT(open()));

    saveAction = new QAction(tr("&Save"), this);
    saveAction->setIcon(QIcon(":/images/save.png"));
    saveAction->setShortcut(QKeySequence::Save);
    saveAction->setStatusTip(tr("Save the spreadsheet to disk"));
    connect(saveAction, SIGNAL(triggered()), this, SLOT(save()));

    saveAsAction = new QAction(tr("Save &As..."), this);
    saveAsAction->setStatusTip(tr("Save the spreadsheet under a new "
                                  "name"));
    connect(saveAsAction, SIGNAL(triggered()), this, SLOT(saveAs()));

    for (int i = 0; i < MaxRecentFiles; ++i) {
        recentFileActions[i] = new QAction(this);
        recentFileActions[i]->setVisible(false);
        connect(recentFileActions[i], SIGNAL(triggered()),
                this, SLOT(openRecentFile()));
    }

    exitAction = new QAction(tr("E&xit"), this);
    exitAction->setShortcut(tr("Ctrl+Q"));　　//没有用于终止应用程序的标准化键序列，需明确指定键序列
    exitAction->setStatusTip(tr("Exit the application"));
    connect(exitAction, SIGNAL(triggered()), this, SLOT(close()));

    cutAction = new QAction(tr("Cu&t"), this);
    cutAction->setIcon(QIcon(":/images/cut.png"));
    cutAction->setShortcut(QKeySequence::Cut);
    cutAction->setStatusTip(tr("Cut the current selection's contents "
                               "to the clipboard"));
    connect(cutAction, SIGNAL(triggered()), spreadsheet, SLOT(cut()));

    copyAction = new QAction(tr("&Copy"), this);
    copyAction->setIcon(QIcon(":/images/copy.png"));
    copyAction->setShortcut(QKeySequence::Copy);
    copyAction->setStatusTip(tr("Copy the current selection's contents "
                                "to the clipboard"));
    connect(copyAction, SIGNAL(triggered()), spreadsheet, SLOT(copy()));

    pasteAction = new QAction(tr("&Paste"), this);
    pasteAction->setIcon(QIcon(":/images/paste.png"));
    pasteAction->setShortcut(QKeySequence::Paste);
    pasteAction->setStatusTip(tr("Paste the clipboard's contents into "
                                 "the current selection"));
    connect(pasteAction, SIGNAL(triggered()),
            spreadsheet, SLOT(paste()));

    deleteAction = new QAction(tr("&Delete"), this);
    deleteAction->setShortcut(QKeySequence::Delete);
    deleteAction->setStatusTip(tr("Delete the current selection's "
                                  "contents"));
    connect(deleteAction, SIGNAL(triggered()),
            spreadsheet, SLOT(del()));

    selectRowAction = new QAction(tr("&Row"), this);
    selectRowAction->setStatusTip(tr("Select all the cells in the "
                                     "current row"));
    connect(selectRowAction, SIGNAL(triggered()),
            spreadsheet, SLOT(selectCurrentRow()));

    selectColumnAction = new QAction(tr("&Column"), this);
    selectColumnAction->setStatusTip(tr("Select all the cells in the "
                                        "current column"));
    connect(selectColumnAction, SIGNAL(triggered()),
            spreadsheet, SLOT(selectCurrentColumn()));

    selectAllAction = new QAction(tr("&All"), this);
    selectAllAction->setShortcut(QKeySequence::SelectAll);
    selectAllAction->setStatusTip(tr("Select all the cells in the "
                                     "spreadsheet"));
    connect(selectAllAction, SIGNAL(triggered()),
            spreadsheet, SLOT(selectAll()));　　//selectAll()是系统提供

    findAction = new QAction(tr("&Find..."), this);
    findAction->setIcon(QIcon(":/images/find.png"));
    findAction->setShortcut(QKeySequence::Find);
    findAction->setStatusTip(tr("Find a matching cell"));
    connect(findAction, SIGNAL(triggered()), this, SLOT(find()));

    goToCellAction = new QAction(tr("&Go to Cell..."), this);
    goToCellAction->setIcon(QIcon(":/images/gotocell.png"));
    goToCellAction->setShortcut(tr("Ctrl+G"));
    goToCellAction->setStatusTip(tr("Go to the specified cell"));
    connect(goToCellAction, SIGNAL(triggered()),
            this, SLOT(goToCell()));

    recalculateAction = new QAction(tr("&Recalculate"), this);
    recalculateAction->setShortcut(tr("F9"));
    recalculateAction->setStatusTip(tr("Recalculate all the "
                                       "spreadsheet's formulas"));
    connect(recalculateAction, SIGNAL(triggered()),
            spreadsheet, SLOT(recalculate()));

    sortAction = new QAction(tr("&Sort..."), this);
    sortAction->setStatusTip(tr("Sort the selected cells or all the "
                                "cells"));
    connect(sortAction, SIGNAL(triggered()), this, SLOT(sort()));

    showGridAction = new QAction(tr("&Show Grid"), this);
    showGridAction->setCheckable(true);　　//复选动作，显示时会带一个复选标记
    showGridAction->setChecked(spreadsheet->showGrid());
    showGridAction->setStatusTip(tr("Show or hide the spreadsheet's "
                                    "grid"));
    connect(showGridAction, SIGNAL(toggled(bool)),
            spreadsheet, SLOT(setShowGrid(bool)));
#if QT_VERSION < 0x040102
    // workaround for a QTableWidget bug in Qt 4.1.1
    connect(showGridAction, SIGNAL(toggled(bool)),
            spreadsheet->viewport(), SLOT(update()));
#endif

    autoRecalcAction = new QAction(tr("&Auto-Recalculate"), this);
    autoRecalcAction->setCheckable(true);
    autoRecalcAction->setChecked(spreadsheet->autoRecalculate());
    autoRecalcAction->setStatusTip(tr("Switch auto-recalculation on or "
                                      "off"));
    connect(autoRecalcAction, SIGNAL(toggled(bool)),
            spreadsheet, SLOT(setAutoRecalculate(bool)));

    aboutAction = new QAction(tr("&About"), this);
    aboutAction->setStatusTip(tr("Show the application's About box"));
    connect(aboutAction, SIGNAL(triggered()), this, SLOT(about()));

    aboutQtAction = new QAction(tr("About &Qt"), this);
    aboutQtAction->setStatusTip(tr("Show the Qt library's About box"));
    connect(aboutQtAction, SIGNAL(triggered()), qApp, SLOT(aboutQt()));　　//通过访问qApp全局变量，使用QApplication对象的aboutQt()槽
}

包含动作的菜单：

void MainWindow::createMenus()
{
    fileMenu = menuBar()->addMenu(tr("&File"));　　//创建一个QMenu窗口部件，并且把它添加到菜单栏
    fileMenu->addAction(newAction);
    fileMenu->addAction(openAction);
    fileMenu->addAction(saveAction);
    fileMenu->addAction(saveAsAction);
    separatorAction = fileMenu->addSeparator();
    for (int i = 0; i < MaxRecentFiles; ++i)
        fileMenu->addAction(recentFileActions[i]);
    fileMenu->addSeparator();
    fileMenu->addAction(exitAction);

    editMenu = menuBar()->addMenu(tr("&Edit"));
    editMenu->addAction(cutAction);
    editMenu->addAction(copyAction);
    editMenu->addAction(pasteAction);
    editMenu->addAction(deleteAction);

    selectSubMenu = editMenu->addMenu(tr("&Select"));
    selectSubMenu->addAction(selectRowAction);
    selectSubMenu->addAction(selectColumnAction);
    selectSubMenu->addAction(selectAllAction);

    editMenu->addSeparator();
    editMenu->addAction(findAction);
    editMenu->addAction(goToCellAction);

    toolsMenu = menuBar()->addMenu(tr("&Tools"));
    toolsMenu->addAction(recalculateAction);
    toolsMenu->addAction(sortAction);

    optionsMenu = menuBar()->addMenu(tr("&Options"));
    optionsMenu->addAction(showGridAction);
    optionsMenu->addAction(autoRecalcAction);

    menuBar()->addSeparator();　　//插入间隔器

    helpMenu = menuBar()->addMenu(tr("&Help"));
    helpMenu->addAction(aboutAction);
    helpMenu->addAction(aboutQtAction);
}

上下文菜单

void MainWindow::createContextMenu()
{
    spreadsheet->addAction(cutAction);　　//将所需动作添加到窗口部件
    spreadsheet->addAction(copyAction);
    spreadsheet->addAction(pasteAction);
    spreadsheet->setContextMenuPolicy(Qt::ActionsContextMenu);　//将这个窗口部件的上下文菜单策略设置为一个显示这些动作的上下文菜单　
}

创建工具栏

void MainWindow::createToolBars()
{
    fileToolBar = addToolBar(tr("&File"));
    fileToolBar->addAction(newAction);
    fileToolBar->addAction(openAction);
    fileToolBar->addAction(saveAction);

    editToolBar = addToolBar(tr("&Edit"));
    editToolBar->addAction(cutAction);
    editToolBar->addAction(copyAction);
    editToolBar->addAction(pasteAction);
    editToolBar->addSeparator();
    editToolBar->addAction(findAction);
    editToolBar->addAction(goToCellAction);
}

创建状态栏；

void MainWindow::createStatusBar()
{
    locationLabel = new QLabel(" W999 ");
    locationLabel->setAlignment(Qt::AlignHCenter);　　//水平居中对齐
    locationLabel->setMinimumSize(locationLabel->sizeHint());

    formulaLabel = new QLabel;
    formulaLabel->setIndent(3);　　//添加了一个缩进格式

    statusBar()->addWidget(locationLabel);
    statusBar()->addWidget(formulaLabel, 1);　　//指定一个伸展因子1

    connect(spreadsheet, SIGNAL(currentCellChanged(int, int, int, int)),
            this, SLOT(updateStatusBar()));
    connect(spreadsheet, SIGNAL(modified()),
            this, SLOT(spreadsheetModified()));

    updateStatusBar();
}

 

 

 

附加小知识：

qt支持BMP,GIF,JPEG,PNG,PNM,SVG,TIFF,XBM 和 XPM等图片格式

qt的资源机制：

　　将图片存放在源代码树中的images目录下，创建一个资源文件，如spreadsheet.qrc，在.pro文件中添加一行RESOURCES = spreadsheet.qrc ，所有资源文件都会被编译到应用程序的可执行文件中，当引用这些资源时，需要使用带路径前缀:/（冒号斜线）的形式。如 setWindowIcon(QIcon(":/images/icon.png"));

spreadsheet.qrc

<RCC>
<qresource>
    <file>images/icon.png</file>
    <file>images/new.png</file>
    <file>images/open.png</file>
    <file>images/save.png</file>
    <file>images/cut.png</file>
    <file>images/copy.png</file>
    <file>images/paste.png</file>
    <file>images/find.png</file>
    <file>images/gotocell.png</file>
</qresource>
</RCC>

action的快捷键：通过使用适当的QKeySequence::StandardKey枚举值，可以确保程序在其运行的平台上提供正确的快捷键

在Qt中，菜单都是QMenu的实例

一个字菜单和它所属的菜单一样，也是一个QMenu

一种更为高级的提供上下文菜单方法是重新实现QWidget::contexMenuEvent()函数，创建一个QMenu窗口部件，在其中添加所期望的那些动作，并且再对该窗口部件调用exec()函数

QMainWindow::statusBar()函数返回一个指向状态栏的指针，在第一次调用statusBar()的时候会创建状态栏