【QT】C++ GUI Qt4 学习笔记3

菜单界面的实现。

看书上第三章，好长，好多代码。我敲了半天，想看看效果，结果却显示不出来。仔细一看，发现spreadsheet的实现在第四章。郁闷....

又到官网上下代码，结果居然不能运行。难道是因为我的版本太高了？

只好自己改，把没实现的部分都先忽略掉，即忽略掉具体的功能，只是显示菜单。折腾了半天，搞定了。

总结一下：

创建菜单：

需要再主窗口类中声明

1.QMenu * 代表一个菜单

2.QAction * 代表菜单中的一个动作 一般一个菜单里会有很多歌动作

3.每个动作对应的槽函数

然后在实现中：

QMenu 的创建，拿fileMenu举例：

主要是1.在窗口中生成菜单 2.添加动作 

//文件菜单

    fileMenu = menuBar()->addMenu(tr("&File")); //设置显示的名称 

    fileMenu->addAction(newAction); //添加动作

    fileMenu->addAction(openAction);

    fileMenu->addAction(saveAction);

    fileMenu->addAction(saveAsAction);

    separatorAction = fileMenu->addSeparator(); //插入间隔器

    for(int i = 0; i < MaxRecentFiles; i++)

    {

        fileMenu->addAction(recentFileActions[i]);

    }

    fileMenu->addSeparator();

    fileMenu->addAction(exitAction);

QAction 的创建,主要包括：

1.新建动作

2.设置动作的图标

3.设置快捷键

4.设置提示 （好奇怪，我设置的提示都显示不出来）

5.添加信号和槽的连接 

拿newAction举例：

    newAction = new QAction(tr("&New"),this);

    newAction->setIcon(QIcon(":file/images/icon.jpg"));

    newAction->setShortcut(QKeySequence::New); //有标准化序列的 没有就用 tr("Ctrl + Q") 之类的

    newAction->setStatusTip(tr("Create a new spreadsheet file"));

    connect(newAction, SIGNAL(triggered()),this, SLOT(newFile()));

功能函数：

由于只看看样子，都设成空函数就好了。

创建工具栏：

需要声明 QToolBar *

需要的动作和上面是一样的

创建：

    fileToolBar = addToolBar(tr("&File"));

    fileToolBar->addAction(newAction);

    fileToolBar->addAction(openAction);

    fileToolBar->addAction(saveAction);

创建状态栏：

用 QLabel

 

代码如下：

mainwindow.cpp

#include "mainwindow.h"

#include "ui_mainwindow.h"

#include "finddialog.h"

#include "gotocelldialog.h"

#include "sortdialog.h"



MainWindow::MainWindow()

{

    //spreadsheet = new Spreadsheet;

    //setCentralWidget(spreadsheet); //设置sheet为主窗口的中央窗口



    //创建主窗口的其他部分



    createActions();

    createMenus();

    //createContextMenu();

    createToolBars();

    //createStatusBar();

    //读取应用程序存储的设置

    //readSettings();

    //find 初始化为空指针

    //findDialog = 0;



    setWindowIcon(QIcon(":file/images/icon.jpg"));

    //setCurrentFile("");

}



void MainWindow::createActions()

{

    /**************File 菜单动作创建***************************/

    //新建

    newAction = new QAction(tr("&New"),this);

    newAction->setIcon(QIcon(":file/images/icon.jpg"));

    newAction->setShortcut(QKeySequence::New);

    newAction->setStatusTip(tr("Create a new spreadsheet file"));

    connect(newAction, SIGNAL(triggered()),this, SLOT(newFile()));

    //打开

    openAction = new QAction(tr("&Open"),this);

    openAction->setIcon(QIcon(":file/images/icon.jpg"));

    openAction->setShortcut(QKeySequence::Open);

    openAction->setStatusTip(tr("Open a file"));

    connect(openAction, SIGNAL(triggered()),this, SLOT(open()));

    //保存

    saveAction = new QAction(tr("&Save"),this);

    saveAction->setIcon(QIcon(":file/images/icon.jpg"));

    saveAction->setShortcut(QKeySequence::Save);

    saveAction->setStatusTip(tr("Save the file"));

    connect(saveAction, SIGNAL(triggered()),this, SLOT(save()));

    //另存为

    saveAsAction = new QAction(tr("&Save As"),this);

    saveAsAction->setIcon(QIcon(":file/images/icon.jpg"));

    saveAsAction->setShortcut(QKeySequence::SaveAs);

    saveAsAction->setStatusTip(tr("Save the file As"));

    connect(saveAsAction, SIGNAL(triggered()),this, SLOT(saveAs()));

    //最近打开的文件



    for(int i = 0; i < MaxRecentFiles; i++)

    {

        recentFileActions[i] = new QAction(this);

        recentFileActions[i]->setVisible(false);

        connect(recentFileActions[i], SIGNAL(triggered()),this,SLOT(openRecentFile()));

    }



    //退出

    exitAction = new QAction(tr("E&xit"),this);

    exitAction->setShortcut(tr("Ctrl+Q"));//没有终止程序的标准化序列键 需要明确指定

    exitAction->setStatusTip(tr("Exit the application"));

    connect(exitAction, SIGNAL(triggered()),this,SLOT(close()));



    /********************Edit 菜单动作创建***************************/

    cutAction = new QAction(tr("Cu&t"), this);

    cutAction->setIcon(QIcon(":file/images/icon.jpg"));

    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(":file/images/icon.jpg"));

    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(":file/images/icon.jpg"));

    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()));



    //全选

    selectAllAction = new QAction(tr("&All"),this);

    selectAllAction->setShortcut(QKeySequence::SelectAll);

    selectAllAction->setStatusTip(tr("Select all the cells in the 'spreadsheet'"));

    connect(selectAllAction, SIGNAL(triggered()),this, SLOT(selectAll())); //Qt已经实现了全选



    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()));



    findAction = new QAction(tr("&Find..."), this);

    findAction->setIcon(QIcon(":file/images/icon.jpg"));

    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(":file/images/icon.jpg"));

    goToCellAction->setShortcut(tr("Ctrl+G"));

    goToCellAction->setStatusTip(tr("Go to the specified cell"));

    connect(goToCellAction, SIGNAL(triggered()),

            this, SLOT(goToCell()));



    /********************Tools 菜单动作创建***************************/

    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()));



   /********************options 菜单动作创建***************************/

    //显示网格  用切换按钮 toggle

    showGridAction = new QAction(tr("&Show Grid"),this);

    showGridAction->setCheckable(true);

    //showGridAction->setChecked(spreadsheet->showGrid());

    showGridAction->setStatusTip(tr("Show or hide the spreadsheet's grid"));

    //connect(showGridAction, SIGNAL(toggled(bool)),this, SLOT(setShowGrid(bool)));



    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()));

}





void MainWindow::createMenus()

{

    //文件菜单

    fileMenu = menuBar()->addMenu(tr("&File"));

    fileMenu->addAction(newAction);

    fileMenu->addAction(openAction);

    fileMenu->addAction(saveAction);

    fileMenu->addAction(saveAsAction);

    separatorAction = fileMenu->addSeparator(); //插入间隔器

    for(int i = 0; i < MaxRecentFiles; i++)

    {

        fileMenu->addAction(recentFileActions[i]);

    }

    fileMenu->addSeparator();

    fileMenu->addAction(exitAction);



    //编辑菜单

    editMenu = menuBar()->addMenu(tr("&Edit"));

    editMenu->addAction(cutAction);

    editMenu->addAction(copyAction);

    editMenu->addAction(pasteAction);

    editMenu->addAction(deleteAction);

    selectSubMenu = editMenu->addMenu(tr("&Select")); //edit菜单的子菜单

    selectSubMenu->addAction(selectRowAction);

    selectSubMenu->addAction(selectColumnAction);

    selectSubMenu->addAction(selectAllAction);

    editMenu->addSeparator();

    editMenu->addAction(findAction);

    editMenu->addAction(goToCellAction);



    //工具菜单

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

    toolsMenu->addAction(recalculateAction);

    toolsMenu->addAction(sortAction);



    //options 菜单

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

    optionsMenu->addAction(showGridAction);

    optionsMenu->addAction(autoRecalcAction);





    menuBar()->addSeparator();



    //help 菜单

    helpMenu = menuBar()->addMenu(tr("&Help"));

    helpMenu->addAction(aboutAction);

    helpMenu->addAction(aboutQtAction);

}





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);

}



void MainWindow::createStatusBar()

{

    locationLabel = new QLabel(" W999 ");

    locationLabel->setAlignment(Qt::AlignHCenter);

    locationLabel->setMinimumSize(locationLabel->sizeHint());



    formulaLabel = new QLabel;

    formulaLabel->setIndent(3);



    statusBar()->addWidget(locationLabel);

    statusBar()->addWidget(formulaLabel, 1);



    //connect(spreadsheet, SIGNAL(currentCellChanged(int, int, int, int)),

    //        this, SLOT(updateStatusBar()));

    //connect(spreadsheet, SIGNAL(modified()),

    //        this, SLOT(spreadsheetModified()));



    //updateStatusBar();

}



bool MainWindow::okToContinue()

{

    if (isWindowModified()) {

        int r = QMessageBox::warning(this, tr("Spreadsheet"),

                        tr("The document has been modified.\n"

                           "Do you want to save your changes?"),

                        QMessageBox::Yes | QMessageBox::No

                        | QMessageBox::Cancel);

        if (r == QMessageBox::Yes) {

            return save();

        } else if (r == QMessageBox::Cancel) {

            return false;

        }

    }

    return true;

}



void MainWindow::newFile()

{

    if (okToContinue()) {

    }

}



void MainWindow::open()

{

    if (okToContinue()) {

    }

}



bool MainWindow::save()

{

    if (curFile.isEmpty()) {

        return saveAs();

    } else {

        return saveFile(curFile);

    }

}



bool MainWindow::saveAs()

{

    return false;

}



void MainWindow::openRecentFile()

{

}



bool MainWindow::saveFile(const QString &fileName)

{

    return true;

}

mainwindow.h

#ifndef MAINWINDOW_H

#define MAINWINDOW_H



#include <QMainWindow>

#include <QMessageBox>

class QAction;

class QLabel;

class FindDialog;

class Spreadsheet;



class MainWindow : public QMainWindow

{

    Q_OBJECT



public:

    MainWindow();



//protected:

 //   void closeEvent(QCloseEvent * event); //QWidget类中的虚函数 重新实现 可以询问是否保存

private slots:

    void newFile();

    void open();

    bool save();

    bool saveAs();

//    void find();

//    void goToCell();

//    void sort();

//    void about();

    void openRecentFile();

//    void updateStatusBar();

//    void SpreadsheetModified();





private:

    void createActions();

    void createMenus();

//   void createContextMenu();

    void createToolBars();

    void createStatusBar();

//    void readSettings();

//    void writeSettings();

    bool okToContinue();

//    bool loadFile(const QString &fileName);

    bool saveFile(const QString &fileName);

//    void setCurrentFile(const QString &fileName);

//    void updateRecentFileActions();

//    QString strippedName(const QString &fullFileName);



//    Spreadsheet *spreadsheet;

//   FindDialog *findDialog;



//    QStringList recentFiles;

    QString curFile;





    /**********菜单栏*************/

    QMenu *fileMenu;

    QMenu *editMenu;

    QMenu *selectSubMenu;

    QMenu *toolsMenu;

    QMenu *optionsMenu;

    QMenu *helpMenu;

    enum{MaxRecentFiles = 5};

    QAction *recentFileActions[MaxRecentFiles];

    QAction *separatorAction;



    /*********工具栏**********/

    QToolBar * fileToolBar;

    QToolBar * editToolBar;



    /***********状态栏*********/

    QLabel * locationLabel;

    QLabel * formulaLabel;





    //file菜单选项

    QAction * newAction;

    QAction * openAction;

    QAction * saveAction;

    QAction * saveAsAction;

    QAction * exitAction;

    //edit菜单选项

    QAction * cutAction;

    QAction * copyAction;

    QAction * pasteAction;

    QAction * deleteAction;

    QAction * selectColumnAction;

    QAction * selectRowAction;

    QAction * selectAllAction;

    QAction * findAction;

    QAction * goToCellAction;

    //tools菜单选项

    QAction * recalculateAction;

    QAction * sortAction;

    //options菜单选项

    QAction * showGridAction;

    QAction * autoRecalcAction;

    //help菜单选项

    QAction * aboutAction;

    QAction * aboutQtAction;





};



#endif // MAINWINDOW_H

main.cpp

#include "mainwindow.h"

#include <QApplication>



int main(int argc, char *argv[])

{

    QApplication a(argc, argv);

    MainWindow w;

    w.show();



    return a.exec();

}

效果如下：我偷懒，所有的图标都用同一张图。图是我用processing画的，是匡的第一个拼音K，哈哈。