Kristian Rietveld wrote: > On Sat, Nov 17, 2007 at 10:54:45PM +0100, Yann Leboulanger wrote: >> I'd like to use Drag and drop on a treeview that gets data in a >> TreeModelFilter. Of course at the begining I got this error: >> >> [snip] >> >> So what I understood is that I had to write a drag_drop handler and put >> my code there instead of in the drag_data_received handler and finish by >> stopping the propagation of the event. Am I right? > > You could indeed go that way and write a drag_drop handler. Since you > will have to use gtk_drag_get_data() to retrieve the actual data that > was dropped, you will probably end up implementing your own handler for > drag_data_received as well (because gtk_drag_get_data() will trigger > drag_data_received). Note that the default implementations of both of > those handlers in GtkTreeView are not trivial at all; they contain logic > to handle several special corner cases (drops on empty views, etc). > >> If so, the problem is that drag_drop handler don't get selection_data >> and info parameters. Is there a way to get them? For selection_data this >> can be a global variable, but for info, I don't see how to know if the >> drop happend on a row, between 2 rows ... > > GtkTreeView just uses the (x, y) coordinates to figure out where you > dropped. To determine if the user dropped in between or on a row, it > just calculates where on the row the user dropped (vertically of > course). If it was close to the row's edge, it will drop before or > after; if the drop was closer to the middle of the row it will drop > into. See gtk_tree_view_get_dest_row_at_pos(). > > Instead of replicating this tree view code, it might be well easier to > derive a new class from GtkTreeModelFilter and implement the > GtkTreeDragDest here. See GtkTreeModelSort for an example how the > GtkTreeDragDest implementation would look like, it should be very > similar. I just had a look at gtktreemodelfilter.c in gtk+-2.10.14, and I don't see what has to be done. gtk_tree_model_filter_row_draggable, gtk_tree_model_filter_drag_data_get, gtk_tree_model_filter_drag_data_delete functions have code, and there is no more function in tree gtktreemodelsort.c about TreeDragSource interface. What did I miss? > At some point in the future the GtkTreeModelFilter might > implement the GtkTreeDragDest interface by default, but all kinds of > interesting problems turn up, such as: > > ROW 1 > [row 2] > [row 3] > ROW 4 > > say rows 2 and 3 are hidden. The tree view will only display row 1 and > 4. Say the user drops a row in between row 1 and 4, where would you > insert it in the original model, where row 2 and 3 do exist and are > "visible"? My "root" model has a sort function, so that should handle this case. > > > I hope this clears things up a bit. > > > regards, > > -kris. > -- Yann _______________________________________________ gtk-list mailing list gtk-list@xxxxxxxxx http://mail.gnome.org/mailman/listinfo/gtk-list
