Custom listbox with button

General JUCE discussion
1

I custom my list box with flowing code, with column id =5 is button
and when listbox shows first time,the button not show.
click one row and the buttons shows.and click another row, buttons will disappear

is there any thing wrong?

Component* refreshComponentForCell(int rowNumber, int columnId, bool
/isRowSelected/,
Component* existingComponentToUpdate) override
{
//jassert(existingComponentToUpdate == nullptr);
// The other columns are editable text columns, for which we use the custom
Label component

  if (columnId == 5) {
  	auto btaction = static_cast<TextButton*>(existingComponentToUpdate);
  	if (rowNumber < vec.size())
  	{
  		if (!btaction){
  		btaction = new TextButton(TRANS("Modify"));
  			btaction->onClick = ([this,rowNumber] {
  				  
  				}));
  			});
  			btaction->setVisible(true);
  	}
  else
  	{ 
  		delete existingComponentToUpdate;
  	btaction = nullptr;
  	} 
  	return btaction;
  }
  }
  else {
  auto* textLabel = static_cast<Label*> (existingComponentToUpdate);
  if (textLabel != nullptr) {
  		return textLabel;
  	}

}

>	return nullptr;    // [10]

}