class Tab : public QTabWidget
 {
 Q_OBJECT
 public:
 Tab(QWidget *parent = );
 QTabBar* GetBar();
 protected:
 void mousePressEvent(QMouseEvent *event);
 }; 

#ifndef MYEVENTFILTER_H
 #define MYEVENTFILTER_H
 #include <QMainWindow>
 #include <QMouseEvent>
 #include "tab.h"
 extern int tabindex_current;
 extern int tabindex_old;
 extern Tab *tabWidget;
 extern QPoint tableft;
 extern int tabwidth;
 extern int tabheight;
 //实现双击关闭Tab标签
 class myEventFilter: public QObject
 {
 public:
 myEventFilter():QObject()
 {};
 ~myEventFilter(){};
 bool eventFilter(QObject* object,QEvent* event)
 {
 if (event->type()==QEvent::MouseButtonDblClick)
 {
  QMouseEvent *e = static_cast<QMouseEvent*>(event);
  QPoint pos = e->pos();
  int x = tableft.x();
  int x = tableft.x()+tabwidth;
  int y = tableft.y();
  int y = tableft.y()+tabheight;
  if (pos.x() >= x && pos.y() >= y && pos.x() <= x && pos.y() <= y)
  tabWidget->removeTab(tabindex_current);
 }
 return QObject::eventFilter(object,event);
 };
 };
 #endif // MYEVENTFILTER_H 

 void MainWindow::updateBar()
 {
 tabindex_current = tabWidget->currentIndex();
 tabindex_old = tabindex_current;
 QTabBar *bar = tabWidget->GetBar();
 if (bar->size().width() > )
  tabwidth = bar->size().width();
 }