beginInsertRows seems not to be working

Hi all,

I have my own model SettingsTreeModel (which is editable) and here is the part of my code:

Code:

---

bool SettingsTreeModel::setData(const QModelIndex &index, const QVariant &value, int role)
{     
 
StackTrace st("stm setdata");          
if (role != Qt::EditRole)         
	return false;     
SettingsNode *node = static_cast<SettingsNode *>(index.internalPointer());      
QStringList attributeList;
switch(index.column()) {         
	case 0:             
    	node->setName(value.toString());             
    	break; 
	case 1:             
    	node->setAttributeMap(AttributeMap(value.toString()));             
    	break; 
	case 2:             
    	beginInsertRows(index,0,0); //a new row may be prepended.
    	st.addExtraInfo(QString("beginInsertRows(%1, %2, %3)").arg(reinterpret_cast<unsigned>(index.internalPointer())).arg(0).arg(0));
    	node->setValue(value.toString()); 
    	endInsertRows();    //maybe?             
    	break;         
	default:             
    	return false;         
}      
emit dataChanged(index, index);      
return true; 
}

---

Here the data is changed (new row is inserted) but view doesn't show it. why do u think?

btw, i tested my model againist qt labs' modeltest and there isn't any error.

It is hard for me to understand what you are doing :P QAbstractItemModel::setData() is for setting data to existing index. You set your value to your internal structure "node" so I don't see any reason for model to insert any additional row - so there is no reason to call beginInsertRows() or endInsertRows(), which dont insert any rows - just notify view etc about inserting new rows. And I suggest implementing rows inserting in QAbstractItemModel::insertRow() or QAbstractItemModel::insertRows().

Here is the story about inserting rows in setData:

this is a kind of tree xml editor, something similar to Simple DOM Model Example (http://doc.trolltech.com/4.2/itemvie...edommodel.html). I already have QAbstractItemModel::insertRow() and QAbstractItemModel::insertRows() implemented, and I called beginInsertRows and it works fine.

What I did here is this: In DOM specification(http://www.w3.org/TR/REC-DOM-Level-1/), it says that any node which has a text value, will be interpreted like having it's first child element(a text node) with the value of the text.

So when editing an existing xml file, if there is a node not having any child or value, when user wants to set its value, i should add a child to this node (before any child) and it should be a text node. anyway, i somehow implemented it, and when i edit the value of a node which didn't have any value before, view shows nothing, but when i save file and reload it, i see that actually internally what i wanted has happened and the node has a new child element (#text) and value is set.

my question is, why i don't see updated tree? any ideas? I can paste here any code on request.

the thing is that if you use setData() it is meant that you set data to the existing index. How are editing value node if there is no such node? I don't understand it, because you want to edit not existing index in your model which will make this model to insert this index...
Then my advice is to insert a new node (index) with insertRow() and then edit its value.