Consider whether wl_data_offer::accept should really require a MIME type
Submitted by Michael Catanzaro
Assigned to Wayland bug list
I have a Wayland client that would like to send wl_data_offer::accept requests when acting as the drag destination, to indicate if drag data would be accepted for the current location of the pointer. However, my client is unable to guarantee which MIME type it will eventually choose to receive data for. It therefore picks the first MIME type it could ever possibly use, and passes that MIME type to wl_data_offer::accept, even if it will eventually decide not to use that MIME type. This enhances the user experience during a DnD session by encouraging the drag source to display a cursor image that indicates the drag will be accepted, but some clients might choose a non-ideal drag image based on the potentially-misleading MIME type my client has accepted.
It would be nice if there was a way to indicate that some MIME type would be accepted for the current pointer location, without committing to any particular MIME type. Passing NULL for the mime_type parameter would be ideal for this, except that is a reject message.