I am trying to use value relation widget (working on QGIS) in Qfield (which should be implemented in the latest releases).
I'm trying to use the widget to filter a long list of plant species. A first table contains all the letters of the alphabet. A second table contains the species and a field with the respective initial of the species.
The polygonal gpkg vector (habitat) requires to fill two fields for the insertion of a species. The first field allows you to choose the initial letter. In the second field you choose the species in a list filtered with the initial letter chosen previously.
On QGis it works, while on Qfield I see the first field (alphabet letters) and I can choose the letter. But when I open the species dropdown menu I see a long, empty, white dropdown menu. In reality it is the complete list (unfiltered) but invisible (I understood it by choosing at random and then reimporting the project in QGIS where fields where filled, but not filtered on the initial).
I tried with the two tables saved as gpkg, spatialite, csv and dbf. In none of the cases did it work.
Tested with version 1.4.4 and 1.5.1 - Piz Palü. Tested with Tablet Samsung Tab Active 2 and Smartphone Lenovo P2
Here a couple screenshots