[QGIS-Developer] UI for enum Processing parameters

[Alexander Bruy]

Hi,

currently Processing uses pop-up dialog for enum parameters with multiple
selection allowed and combobox for enums with single selection. The good
thing about pop-up dialog is that very large lists are easier to manage, but
at the same time I don't think there are/will be algorithms with many
enum values.
On other hand opening pop-up on top of the algorithm dialog can be considired
as bad UI, also this is a bit not consistent with single-selection enum case.

I'm wondering if we should switch multiple selection enums to use checkable
combobox to unify UI with single selection case? Another option will be to use
inline panel approach added by Nyall today.

Opinions?

-- 
Alexander Bruy