Qt for beginners-achieve dynamic addition and deletion of basic components

I again stated that due to my first contact with C ++ and QT, many places are not very familiar, and errors are inevitable. The Code provided only has reference to the exchange value.

Functions:

Use the "addbutton" button to add a component and use the "delbutton" button to delete the component.

The Code is as follows:

/********MainFrame.h************/#ifndef MAINFRAME_H_#define MAINFRAME_H_#include <QtGui/QWidget>#include <QtGui/QPushButton>class MainFrame : public QWidget{  Q_OBJECT  public:  MainFrame();  ~MainFrame();  QWidget *widget;  public slots:  void addButton();  void delButton();};#endif

/**********MainFrame.cpp***********/#include "MainFrame.h"#include <iostream>MainFrame::MainFrame(){  widget=NULL;  setGeometry(0,0,500,300);  QPushButton *button_add=new QPushButton("addButton",this);  QPushButton *button_del=new QPushButton("delButton",this);  button_add->setGeometry(20,20,200,50);  button_del->setGeometry(240,20,200,50);  connect(button_add,SIGNAL(clicked()),this,SLOT(addButton()));  connect(button_del,SIGNAL(clicked()),this,SLOT(delButton()));}MainFrame::~MainFrame(){}void MainFrame::addButton(){   std::cout<<"addButton clicked!"<<std::endl;   if(widget!=NULL){     widget->hide();     widget=NULL;   }   widget=new QWidget(this);   widget->setGeometry(0,120,300,200);   QPushButton *button1=new QPushButton("AAAAAAAAAA",widget);   QPushButton *button2=new QPushButton("BBBBBBBBBB",widget);   button1->setGeometry(20,0,200,50);   button2->setGeometry(20,100,200,50);   widget->show();}void MainFrame::delButton(){   std::cout<<"delButton clicked!"<<std::endl;   if(widget!=NULL){     widget->hide();     widget=NULL;   }}

/**********Main.cpp***********/#include <QtGui/QApplication>#include "MainFrame.h"int main(int argc,char *argv[]){   QApplication a(argc,argv);   MainFrame *my=new MainFrame();   my->show();   return a.exec();}

Run:

Click "addbutton:

After clicking delbutton:

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