容器窗口 <QTabWidget>

 //////////////////////////////////////////
   #include "test9_2a.h"
 #include "M_win.h"

 Test9_2A::Test9_2A(QWidget *parent)
     : QMainWindow(parent)
 {

     ui.setupUi(this);

     M_win *page = new M_win();

     ui.stackedWidget->insertWidget(,page);

     connect(ui.BtnFirst,  SIGNAL(clicked()), this, SLOT(OnBtnFirst()));
     connect(ui.BtnSecond, SIGNAL(clicked()), this, SLOT(OnBtnSecond()));
     connect(ui.BtnThird,  SIGNAL(clicked()), this, SLOT(OnBtnthird()));

 }

 Test9_2A::~Test9_2A()
 {

 }

 int Test9_2A::OnBtnFirst()
 {
     ui.stackedWidget->setCurrentIndex();
     return ;
 }

 int Test9_2A::OnBtnSecond()
 {
     ui.stackedWidget->setCurrentIndex();
     return ;
 }

 int Test9_2A::OnBtnthird()
 {
     ui.stackedWidget->setCurrentIndex();
     return ;
 }