Qt之主窗口设计——基于QMainWindow主窗口程序

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QtGui>


class MainWindow : public QMainWindow
{
	Q_OBJECT

public:
	MainWindow(QWidget *parent = 0, Qt::WFlags flags = 0);
	~MainWindow();

	void createMenus();		//创建菜单
	void createActions();	//创建动作
	void createToolBars();	//创建工具栏
public slots:
	void sl_NewFile();
	void sl_OpenFile();
	void sl_SaveFile();
	void sl_About();
protected:
	void loadFile(QString);

private:
	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 *edtText;	
};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include <QTextStream>
#include <QFile>

MainWindow::MainWindow(QWidget *parent, Qt::WFlags flags)
	: QMainWindow(parent, flags)
{
	setWindowTitle(tr("QMainWindow"));
	edtText = new QTextEdit(this);
	setCentralWidget(edtText);

	createActions();
	createMenus();
	createToolBars();
}

MainWindow::~MainWindow()
{

}

void MainWindow::createActions()
{
	//"打开"动作
	fileOpenAction = new QAction(QIcon("images/open.png"),tr("Open"),this);
	fileOpenAction->setShortcut(tr("Ctrl+0"));
	fileOpenAction->setStatusTip(tr("open a file"));
	connect(fileOpenAction,SIGNAL(triggered()),this,SLOT(sl_OpenFile()));

	//"新建"动作
	fileNewAction = new QAction(QIcon("images/new.png"),tr("New"),this);
	fileNewAction->setShortcut(tr("Ctrl+N"));
	fileNewAction->setStatusTip(tr("new file"));
	connect(fileNewAction,SIGNAL(triggered()),this,SLOT(sl_NewFile()));

	//"保存"动作
	fileSaveAction = new QAction(QIcon("images/save.png"),tr("Save"),this);
	fileSaveAction->setShortcut(tr("Ctrl+S"));
	fileSaveAction->setStatusTip(tr("save file"));
	connect(fileSaveAction,SIGNAL(activated()),this,SLOT(sl_SaveFile()));

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

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

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

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

	//"关于"动作
	aboutAction = new QAction(tr("About"),this);
	connect(aboutAction,SIGNAL(triggered()),this,SLOT(sl_About()));
}

void MainWindow::createMenus()
{
	//文件菜单
	fileMenu = menuBar()->addMenu(tr("File"));
	fileMenu->addAction(fileNewAction);
	fileMenu->addAction(fileOpenAction);
	fileMenu->addAction(fileSaveAction);
	fileMenu->addSeparator();
	fileMenu->addAction(exitAction);

	//编辑菜单
	editMenu = menuBar()->addMenu(tr("Edit"));
	editMenu->addAction(copyAction);
	editMenu->addAction(cutAction);
	editMenu->addAction(pasteAction);

	//帮助菜单
	aboutMenu = menuBar()->addMenu(tr("Help"));
	aboutMenu->addAction(aboutAction);
}

void MainWindow::createToolBars()
{
	//文件工具栏
	fileTool = addToolBar("File");
	fileTool->addAction(fileNewAction);
	fileTool->addAction(fileOpenAction);
	fileTool->addAction(fileSaveAction);
	fileTool->setAllowedAreas(Qt::TopToolBarArea | Qt::LeftToolBarArea);
	fileTool->setMovable(false);

	//编辑工具栏
	editTool = addToolBar("Edit");
	editTool->addAction(copyAction);
	editTool->addAction(cutAction);
	editTool->addAction(pasteAction);
}

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

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

void MainWindow::sl_SaveFile()
{

}

void MainWindow::sl_About()
{

}

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

---

工具条是一个可移动的窗口，它可停靠的区域由QToolBar的allowAreas()函数决定的，它的参数包括：

Qt::LeftToolBarArea、Qt::RightToolBarArea、Qt::TopToolBarArea、Qt::BottomToolBarArea、Qt::AllToolBarArea.

(默认为Qt::AllToolBarArea，启动时默认出现于主窗口的顶部)。

setMovable()函数确定工具条的可移动性。默认参数为true，可移动。

---