my.cpp

qt类库是非微软类库

#include "my.h"
#include<stdlib.h>
MyMainWindow::MyMainWindow()
{
    pb=new QPushButton("E&xit",this);
	pb->setGeometry(20,20,50,30);
	connect(pb,SIGNAL(clicked()),this,SLOT(MyHandle()));
	connect(this,SIGNAL(YY(int)),this,SLOT(MyHandleCancel()));
}
void MyMainWindow::MyHandle()
{
  QMessageBox *kk;
  kk=new QMessageBox("Exit?","Do you want to Exit this process?",
 					QMessageBox::Critical,
 					QMessageBox::Ok|QMessageBox::Default,
 					QMessageBox::Cancel|QMessageBox::Escape,
 					0
	  );
  int i=kk->exec();
  if(i==QMessageBox::Accepted)
	exit(0);
  else
	 emit YY(3);

}

void MyMainWindow::MyHandleCancel()
{
  QMessageBox *tt;
  tt=new QMessageBox("Cancel?","Are you sure to cancel this process?",
 					QMessageBox::Critical,
 					QMessageBox::Ok|QMessageBox::Default,
 					QMessageBox::Cancel|QMessageBox::Escape,
 					0); 
  tt->show();
}