Please create an object like ParentItem as a reference to the current item in parent gallery, in the same way like ThisItem is reference to current item in gallery, it will be very useful during filtering items for nested galery.
I think what you request can be easily done with current functionality.
For filtering you just use ThisItem in the Items property of the nested gallery.
If you need the parent value in the nested gallery template, then you add a column with the parent gallery primary key (e.g. ID) value.
Please let me know if this is not clear or clarify your requirement if you think it cannot be met.
I tried this before, it did not work for some reason. Now I've tried it again, and your solution works perfectly. Thank you!
There are many situations where this may be very useful.In a nested gallery, the child may need access to the parent's columns to do a specific filter to get some additional information to display.
I don't see any workarounds to this unless you want the child's items to be purely a Filter based on ThisItem of the parent which only works on the Gallery level but not individual child item level in the gallery.
In the current scenario that I am working on, The parent gallery is connected to a Tasks table and the child gallery are a table showing all employees available in a project. A label inside this child gallery may be cost, which may need look something like this. Filter(Cost, employee=employID (from child) && task=taskID (fromParent) and this may not be achieveable.