qt listwidget循环添加控件

QVBoxLayout *main_layout = new QVBoxLayout;
   QPushButton *button1 = new QPushButton("button1");
  left = new QListWidget;
  main_layout->addWidget(button1);
  main_layout->addWidget(left);
  connect(button1,SIGNAL(clicked()),this,SLOT(clickedfunc()));
  left->setCurrentRow(2);
  for (int i =0;i< 103; i++) {
      QListWidgetItem * item = new QListWidgetItem;
      item->setSizeHint(QSize(10,100));
      left->addItem(item);
      QWidget * m_w = new QWidget;
      QHBoxLayout * layout = new QHBoxLayout;
      QPushButton *pushbutton = new QPushButton(m_w);
      QCheckBox *chexBox = new QCheckBox(m_w);
      chexBox->setText(QString::number(i));
      layout->addWidget(chexBox);
      layout->addWidget(pushbutton);
      m_w->setLayout(layout);

      left->setItemWidget(item,m_w);
  }
  ui->centralwidget->setLayout(main_layout);