Project Actions or Processing Algorithms

gistfile1.txt

# Summary

The _**Relation Editor Widget**_ is a powerful tool to link children objects to a parent object or - with many-to-many relations - directly choose the "other" parent and perform an entry in the join table. There are options like creating child objects or linking exiting ones.

The "opposite" of it is the **_Relation Reference Widget_**, where we choose the parent object. There a useful feature is the ***filter***.

But in _**Relation Editor Widget**_ we still need to filter manually when we filter objects.

So this would be a very useful feature.

# Example

We do have a layer representing fields named "Beurteilung_Wiese" with a parameter "uzl_subregion" what could be "1.1", "1.2", "1.3", depending where the field is:
![image](https://github.com/user-attachments/assets/d65fb4f4-902d-4369-8818-86b74a1ab1ec)

Now we want to link flora-types to the current "Beurteilung_Wiese", but in the huge list of all the flora-types we only want to have the ones that really exist in the current subregion. Means I need a filter like this:

![image](https://github.com/user-attachments/assets/25ca4913-41fb-4903-aefe-0a55aca789a1)

But this filter I always have to set manually. I would like to have something like this:
![image](https://github.com/user-attachments/assets/3a41ca17-373a-4028-8788-94a601a11510)


![image](https://github.com/user-attachments/assets/24d1edbd-70f5-49bd-9550-99110b9ea0dd)