[PySide] QListView: drag&drop custom item

[Purma Jukka]

Hi,
since you asked any ideas... In my app I have had to re-invent drag&drop for some items (because I want to drag QGraphicsItems in scene while having all kinds of effects on the items they are connected while keeping the main event loop running etc. ) and learned a habit to give up when I didn’t find Qt-way of doing things and instead to choose the simplest pythonesque way.

So in your case at this point, I would have 
1. 'start drag' store the dragged data, just the main payload, not the Q-item containing them, in some stable object (main window), just as ’main.dragged_object’.
2. when drag gets dropped to those problem recipients, in drop event, manually put the data from main window into recipient, without bothering with the Q-representations of the data.

In my app I have a multipurpose controller-object and ctrl.dragged is used to store the non-qt data of whatever is being dragged. It was my solution to struggle with QStandardItems and such.  

In conclusion, since we are doing things with Python + Qt, I think we are justified to skip Qt when there is an easier (or more readable) pythonesque way of doing things. 

Jukka

> Frank Rueter | OHUfx <frank at ohufx.com> kirjoitti 19.9.2016 kello 9.56:
> 
> Anybody?
> I'm still struggling with this. I went back to using a QStandardItem for a while which solved the dag&drop behaviour, but now I really need to use a custom item that inherits QStandardItem which breaks the drop behaviour again.
> 
> Any ideas or guidance would be greatly appreciated.
> 
> Cheers,
> frank
> 
> 
> On 16/08/16 7:26 PM, Frank Rueter | OHUfx wrote:
>> Hi,
>> 
>> I am trying to get drag&drop to work between two QListViews using a custom item.
>> I can't find the info I need online other than this document which helped a little bit but now I'm stuck.
>> 
>> Drag&drop from one QListView to another works fine when I use a QStandardItem to hold my data, but when I use a custom item I run into trouble, because the receiving model/view creates a QStandardItem when the incoming custom items are dropped.
>> 
>> Ideally I could tell the receiving model to use my custom item as the default item and otherwise just do it's thing, but I suppose it won't be that easy?!
>> I have played around with the receiving model's dropMimeData() and insertRows() methods but can't work out how to read the incoming data to then insert a custom item into the receiving model manually.
>> In QAbstractItemModel.dropMimeData() I tried reading mimeData.data('application/x-qabstractitemmodeldatalist'), but that returns a byte stream that I don't know how to handle.
>> 
>> Do I have to re-implement the sender's drag data as well to send the custom item in the first place?
>> 
>> It seems that everything works out of the box except the creation of the QStandardItem upon drop, rather than my custom item, so I am hoping I don't have to re-invent the (drag&drop) wheel just to get that one part right?!
>> 
>> Any advise would be greatly appreciated.
>> 
>> Thanks,
>> frank
>> 
>> 
>> 
>> -- 
>> <Sähköpostiliite.png>	vfx compositing | workflow customisation and consulting
>> 
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