I'm not sure which signals you mean...layoutAboutToBeChanged() or rowsAboutToBeInserted() perhaps?
I think beginInsertRows() will take care of those things

Anyway, this is how my insert mechanism looks like
Is this what you have in mind?

Qt Code: 
  1. bool DomModel::insertRows(int position, int rows, const QModelIndex& parent)
  2.  {
  3.     DomItem *parentItem;
  4.  
  5.     if (!parent.isValid())
  6.         parentItem = rootItem;
  7.     else
  8.         parentItem = static_cast<DomItem*>(parent.internalPointer());
  9.  
  10.     //only need to append one child
  11.     beginInsertRows(parent, position, position);
  12.  
  13.     if(!parentItem->insertChild())
  14.        return false;
  15.  
  16.     endInsertRows();
  17.  
  18.     return true;
  19.  }
  20.  
  21. bool DomItem::insertChild()
  22.  {
  23.     int rows = childItems.count();
  24.  
  25.     QDomNode node;
  26.     DomItem *item = new DomItem(node, rows+1, this);
  27.     domNode.appendChild(node);
  28.     childItems.insert(rows+1, item);
  29.  
  30.     return true;
  31.  }
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I keep getting the same message(which was written wrong in my last post)

QTreeView::rowsInserted internal representation of the model has been corrupted, resetting.

It looks like bad indexing occurs...but I'm not sure why that happens.