关于Qt Event 处理机制

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根据Qt Event 处理机制，分析如下代码：

class MonitorObject : public QObject

{

public:

MonitorObject() {}

protected:

bool eventFilter(QObject*obj, QEvent *event);

};

bool MonitorObject::eventFilter(QObject*obj, QEvent *event)

{

qDebug(“eventFilter\n”);

returnfalse;

}

class MyWidget : public QWidget

{

public:

MyWidget(QWidget* parent = 0): QWidget (parent) {}

protected:

virtual bool event(QEvent *event);

virtual void keyPressEvent(QKeyEvent* event);

};

bool MyWidget::event(QEvent * event)

{

qDebug(“event\n”);

return QWidget::event(event);

}

void MyWidget::keyPressEvent(QKeyEvent *event);

{

qDebug(“keyPressEvent\n”);

MyWidget:: keyPressEvent(event);

}

int main(int argc, char **argv)

{

QApplication a(argc, argv);

MonitorObject *pMonitorObject= new MonitorObject;

MyWidget *pWidget = newMyWidget;

pWidget->installEventFilter(pMonitorObject);

pWidget->show();

return a.exec();

}

启动程序，当键盘事件(Key Press)发生时，列出打印信息。

请大神们帮我看看这个题。谢谢了