Qt中MainWindow类实例

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QLabel>
#include "myview.h"//在mainwindow上再添加一个窗口
#include <QSystemTrayIcon>//托盘

class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
void paintEvent(QPaintEvent *);
void mousePressEvent(QMouseEvent *);
bool event(QEvent *);
QLabel * _label;
MyView * _view;//把要显示的东西都放在这个窗口部件里面；mainWindow起到封装的作用
QMenu * _menu;//用于右键弹出菜单
QSystemTrayIcon * _icon;//托盘图标
void slotActivated(QSystemTrayIcon::ActivationReason);
signals:

public slots:
void slotOpen();
void slotSave();
};

#endif // MAINWINDOW_H

#include "mainwindow.h"
#include <QApplication>
#include <QMenu>//菜单类
#include <QMenuBar>//菜单栏
#include <QAction>//菜单项,是一个可以触发的东西
#include <QFileDialog>
#include <QDebug>
#include <QToolBar>
#include <QStatusBar>
#include <QPainter>
#include <QPixmap>
#include <QMouseEvent>
#include <QCursor>//鼠标当前的位置
#include <QIcon>
#include <QEvent>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent)
{
/*添加菜单*/
QMenuBar * pMenuBar = menuBar();
QMenu *menu = pMenuBar->addMenu("File");
_menu = menu;

QAction *openAction = menu->addAction("&Open", this, SLOT(slotOpen()), QKeySequence::Open);
QAction *saveAction = menu->addAction("&Save", this, SLOT(slotSave()), QKeySequence::Save);
menu->addSeparator();
QAction *closeAction = menu->addAction("&Exit", this, SLOT(close()), QKeySequence::Close);

/*添加工具栏*/
QToolBar *toolBar = this->addToolBar("MyToolBar");//添加一个工具栏
toolBar->addAction(openAction);
toolBar->addAction(saveAction);
toolBar->addAction(closeAction);

/*添加状态栏*/
QStatusBar *pstatusBar = this->statusBar();
pstatusBar->addWidget(_label = new QLabel("OK"));
_label->setText("<font color = red>Processing...</font>");

/*mainwindow中别的控件占用了之后，剩下的区域都是CentralWidget的*/
_view = new MyView;
this->setCentralWidget(_view);

/*托盘*/
_icon = new QSystemTrayIcon;
_icon->setIcon(QIcon("../1.png"));
_icon->setToolTip("This is my tray test");
_icon->show();//显示该托盘图标
_icon->setContextMenu(menu);
connect(_icon, SIGNAL(activated(QSystemTrayIcon::ActivationReason)), this, SLOT(slotActivated(QSystemTrayIcon::ActivationReason)));
}

//这个函数的功能也没有实现
void MainWindow::slotActivated(QSystemTrayIcon::ActivationReason reason)
{
if (reason == QSystemTrayIcon::Trigger){
if (this->isHidden()) this->show();
else this->isHidden();
}
}

//这个函数的功能没有实现
bool MainWindow::event(QEvent *event)
{
if(event->type() == QEvent::Close){
return false;
}
return QMainWindow::event(event);
}

void MainWindow::paintEvent(QPaintEvent *)
{
QPainter p(this);
p.drawPixmap(QPointF(0, 0),QPixmap("../1.png"));
}

void MainWindow::mousePressEvent(QMouseEvent *ev)
{
if(ev->button() == Qt::RightButton)
_menu->exec(QCursor::pos());
}

void MainWindow::slotSave()
{
QFileDialog::getSaveFileName();

}

void MainWindow::slotOpen()
{
QString strFile = QFileDialog::getOpenFileName();
qDebug() << strFile;
}

int main(int argc, char **argv)
{
QApplication app(argc, argv);

MainWindow w;
w.setGeometry(300, 130, 700, 500);
w.show();

app.exec();
}

#ifndef MYVIEW_H
#define MYVIEW_H

#include <QWidget>

class MyView : public QWidget
{
Q_OBJECT
public:
explicit MyView(QWidget *parent = 0);
void paintEvent(QPaintEvent *);
signals:

public slots:

};

#endif // MYVIEW_H

#include "myview.h"
#include <QPainter>

MyView::MyView(QWidget *parent) :
QWidget(parent)
{
}

void MyView::paintEvent(QPaintEvent *)
{
QPainter p(this);
p.fillRect(rect(), Qt::red);
}