Populating dropdown depending on subform value

In the attached database, I have a main form with 3 inter-related subforms.

On the 2nd subform (Collection) you select a Company.
On the 3rd (Collect Raw Material) you select a Raw Material from a dropdown. This dropdown is dependent upon the value of the Company in the 2nd subform. The logic being that each Company is only allowed to have certain Raw Materials collected, so the tbl_company_material dictates which Company is associated to which Raw Material.

So I need the dropdown to be refreshed each time:
A new collection is added in the Collections subform.
When the Company in the Collections subform.
When the Company in the Collections subform is changed
Rick DangerAsked:
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Scott McDaniel (Microsoft Access MVP - EE MVE )Infotrakker SoftwareCommented:
You could perhaps Requery the Subform after those events:

Me.[Collect Raw Material].Form.Requery

If you need to do that from one of the other "sibling" Subforms:

Me.Parent.[Collect Raw Material].Form.Requery

I'd also encourage you to use proper nameing conventions for your objects. The Subform control really should be named sfCollectRawMaterial - no spaces, and (optional) as two or three character prefix that identifies the type of object. While it seems a minor issue, it can have a big impact down the road.

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