Can I get a drag&drop tobe displayed as a line instead of the big floating icon?

[pir]

.../ Or you could even do it even more properly and encode not the index of the item but its data (as should be done with "real" drag&drop).

This fit my purposes best, I think. The only thing my indexes containt is a pointer to a component in my scene. So it should be sufficuent to give this pointer as information... this was actually my first approach but I couldn't find how I was supposted to convert the pointer to a QByteArray and back.

But there is one problem with this approach. I need to be able to remove the old index when the user have dropped the object, since it should be executed as a move action. So I need to find that index, and then I suppose I need to know its row and parent, and the parent's row and parent etc... maybe it's simpler to have a pointer in my model class pointing to the index being dragged and use this information instead of a mime. Could this create problems somehow?

/pir

[wysota]

This fit my purposes best, I think. The only thing my indexes containt is a pointer to a component in my scene. So it should be sufficuent to give this pointer as information... this was actually my first approach but I couldn't find how I was supposted to convert the pointer to a QByteArray and back.

A pointer is an integer, just treat it as such. But if you want to encode the data itself, then I didn't mean a pointer here, but actual information which is stored in an object referenced by the pointer.

But there is one problem with this approach. I need to be able to remove the old index when the user have dropped the object, since it should be executed as a move action.

I guess the view might do it yourself if you convince it you are doing a move action (but I'm not sure, haven't tried it myself yet).

So I need to find that index, and then I suppose I need to know its row and parent, and the parent's row and parent etc...

That's why the concept of indexes exists But if you implement the drop correctly, you won't have to worry about removing the item from its original place.

maybe it's simpler to have a pointer in my model class pointing to the index being dragged and use this information instead of a mime. Could this create problems somehow?

This doesn't give you any advantage. You can store the pointer in the QMimeData object as well.

[Valheru]

What may help you a bit is to look at my source code here : http://code.google.com/p/knewz/source/browse/trunk
I ran into this the other day, it's a bit of work to get right but not terribly complicated once you get the hang of it. There's a few things to remember while dragging and dropping stuff, but you should be able to pick them up from my code if you haven't already.
There pertinant stuff you will want to look at is the model and the mimedata implementations:
http://code.google.com/p/knewz/sourc...knewzmodel.cpp
http://code.google.com/p/knewz/sourc...zbmimedata.cpp

Like you, I am just passing pointers to objects around in a QList. So with a drag and drop you just dump the pointer list into a custom mimedata class and retrieve it when it is dropped. Then you can use your underlying data structure to manipulate the data directly, encapsulating any removal and insertion of rows with the correct calls to being/endRemoveRows and begin/endInsertRows