Copy QStandardItemModel to another

Question

Is there some way to Copy a QStandardItemModel to another QStandardItemModel? Or must I iterate over each tem and append it to the other Model?

Sagittate

You should iterate over each item and COPY (not append) it to another model. – Variegate

Answer 1

An item can be owned by one model only. That is why you need to create a copy of each item and place it to another model. You can do it using method QStandardItem::clone.

This is an example for single column models:

void copy(QStandardItemModel* from, QStandardItemModel* to)
{
   to->clear();
   for (int i = 0 ; i < from->rowCount() ; i++)
   {
      to->appendRow(from->item(i)->clone());
   }
}

EDIT:
Use to->removeRows(0, to->rowCount ()); instead of to->clear(); if you want to keep header data and column sizes in linked views.

Wordbook

In my opinion to->removeRows (0, to->rowCount () ) should be better then to->clear (), because it doesn't remove general settings of model like headers, resize mode, etc. – Heartless

@Heartless A model doesn't have such settings as resize mode. Do you mean that calling clear forces a view to reset column sizes? – Wordbook

Do you mean, Yes, indeed! – Heartless

Answer 2

You could do copy of an existing item with next steps:

1. Get existing item.
2. Create new item.
3. Set necessary data roles from existing item to a new one.
4. Do the same with flags.

Or simply use QStandardItem::clone() method. And reimplement it, if necessary.

Variegate