Qt中的菜单类使用

mainwindow.h:

 

#ifndef __MAINWINDOW_H__
#define __MAINWINDOW_H__

#include <QMainWindow>

class QMenu;
class QAction;
class QLabel;

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

private slots:
   void newFile();
   void openFile();
   void saveFile();
   void printFile();
   void about();
   void bold();
   void italic();
private:
  QMenu* fileMenu; //文件菜单
  QMenu* editMenu; //编辑菜单
  QMenu* helpMenu; //帮助菜单
  QMenu* formatMenu;
    
  QAction* newAct; //新建
  QAction* openAct; //打开
  QAction* saveAct; //保存
  QAction* printAct; //打印
  QAction* exitAct; //退出
  QAction* boldAct;
  QAction* italicAct;
    
  QAction* aboutAct; //关于
  QLabel* infoLabel;
    
   void createActions();
   void createMenus();
};

#endif // __MAINWINDOW_H__

 

 

mainwindow.cpp:

 

#include <QMenu>
#include <QAction>
#include <QMenuBar>
#include <QLabel>
#include <QWidget>
#include <QVBoxLayout>
#include <QStatusBar>
#include <QKeySequence>
#include <QMessageBox>
#include "mainwindow.h"

MainWindow::MainWindow()
{
  QWidget *widget= new QWidget;
  setCentralWidget(widget); //设置中央Widget

  infoLabel= new QLabel( "Choose a menu option,or right-click to invoke action");
  infoLabel->setAlignment(Qt::AlignCenter); //居中对齐
  QVBoxLayout *layout= new QVBoxLayout;
  layout->addWidget(infoLabel);
    
  widget->setLayout(layout);
    
  createActions();
  createMenus();
    
  QString msg= "popup a menu by right-clicking.";
  statusBar()->showMessage(msg);
    
  setWindowTitle(tr( "Menus"));
  setMinimumSize(160,160); //设置最小尺寸
  resize(480,320); //设置尺寸
}

//创建Actions
void MainWindow::createActions()
{
  newAct= new QAction( "&New", this);
  newAct->setShortcut(QKeySequence( "Ctrl+N")); //设置快捷键
  newAct->setStatusTip( "New a file"); //设置状态栏提示
  connect(newAct,SIGNAL(triggered()), this,SLOT(newFile()));
    
         openAct = new QAction( "&Open...", this);
         openAct->setShortcut(tr( "Ctrl+O"));
         openAct->setStatusTip( "Open an existing file");
         connect(openAct, SIGNAL(triggered()), this, SLOT(openFile()));    
            
         saveAct = new QAction( "&Save", this);
         saveAct->setShortcut(tr( "Ctrl+S"));
         saveAct->setStatusTip( "save the    file");
         connect(saveAct, SIGNAL(triggered()), this, SLOT(saveFile()));            
            
         printAct = new QAction( "&Print...", this);
         printAct->setShortcut(tr( "Ctrl+P"));
         printAct->setStatusTip( "Print the    file");
         connect(printAct, SIGNAL(triggered()), this, SLOT(printFile()));                    
            
         exitAct = new QAction( "E&xit", this);
         exitAct->setShortcut(tr( "Ctrl+Q"));
         exitAct->setStatusTip( "Exit the Application.");
         connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));            
            
         boldAct = new QAction(tr( "&Bold"), this);
         boldAct->setCheckable( true); //可选择
         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); //字体加粗
         boldAct->setFont(boldFont); //设置字体
            
         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); //设置倾斜
         italicAct->setFont(italicFont);
            
            
         aboutAct= new QAction( "&About", this);
         aboutAct->setStatusTip( "About the App");
         connect(aboutAct,SIGNAL(triggered()), this,SLOT(about()));
                
}

//创建菜单
void MainWindow::createMenus()
{
   //文件菜单
  fileMenu=menuBar()->addMenu( "&File");
  fileMenu->addAction(newAct);
  fileMenu->addAction(openAct);
  fileMenu->addAction(saveAct);
  fileMenu->addAction(printAct);
  fileMenu->addSeparator();
  fileMenu->addAction(exitAct);
    
   //编辑菜单
  editMenu=menuBar()->addMenu( "&Edit");
  formatMenu=editMenu->addMenu( "&Format");
  formatMenu->addAction(boldAct);
  formatMenu->addAction(italicAct);
    
   //帮助菜单
  helpMenu=menuBar()->addMenu( "&Help");
  helpMenu->addAction(aboutAct);
    
}

void MainWindow::newFile()
{
  infoLabel->setText( "Invoke<b>File|New</b>");
}
void MainWindow::openFile()
{
  infoLabel->setText( "Invoke<b>File|Open</b>");
}
void MainWindow::saveFile()
{
  infoLabel->setText( "Invoke<b>File|Save</b>");
}

void MainWindow::printFile()
{
  infoLabel->setText( "Invoke<b>File|Print</b>");
}

//关于对话框
void MainWindow::about()
{
  infoLabel->setText( "Invoke<b>Help|About</b>");
  QMessageBox::about( this, "About", "How to createMenus");
}

void MainWindow::bold()
{
  infoLabel->setText( "Invoke<b>Edit|Format|bold</b>");
}

void MainWindow::italic()
{
  infoLabel->setText( "Invoke<b>Edit|Format|italic</b>");
}

 

main.cpp:

 

#include <QApplication>
#include "mainwindow.h"

int main( int argc, char* argv[])
{
  QApplication app(argc,argv);
  MainWindow win;
  win.show();
   return app.exec();
}

 

 

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