I don't know that a drop-down menu is possible (afaik), but we do something similar.
We have a store of "generic" images for our OTS scenes, and the producers just navigate to the one image they want to use for each story. The image is just a published object that can be edited in iNews through the MOS plugin. Our creative services and production team manages the generic images, so they have what they need 90% of the time.
As for video materials, that's a different beast (that may have been fixed in newer versions). We cannot currently set videos in a published material. I've been toying with the idea of scripting video changes, so that the producers need only input a character or word into a non-visible field, which will then set the image in the background.
For example:
dim ElectionBK as xpMaterial
dim UrgentBK as xpMaterial
dim GenericBK as xpMaterial
dim BKG as xpBaseObject
dim TxtFlag as xpTextObject
Engine.GetMaterialByName("Election BKG Video", ElectionBK)
Engine.GetMaterialByName("Urgent BKG Video", UrgentBK)
Engine.GetMaterialByName("Generic BKG Video", GenericBK)
Self.GetObjectByName("BKG Video", BKG)
Self.GetObjectByName("Background Type", TxtFlag)
If InStr(Ucase(TxtFlag.Text, "ELECTION")) = 1 then
BKG.SetMaterial(0, ElectionBK)
ElseIf
InStr(Ucase(TxtFlag.Text, "URGENT")) = 1 then
BKG.SetMaterial(0, UrgentBK)
Else
BKG.SetMaterial(0, GenericBK)
End If
Just a thought, I haven't tried it out ever, but don't see why that wouldn't work. There would just be a text field to enter "election" or "urgent" or anything else you might want, then the scene would change the background video for you.
#Carbonite