I have a main form ('MainForm') containing two subforms, both continuous forms, positioned alongside each other ('Subform1' and 'Subform2'). MainForm is unbound, while Subform1 acts as a surrogate parent to Subform2's child.
In this scenario (taken on its own terms, please!), what's the fastest way to filter the records in Subform2 when Subform1 moves to a different record? I can think of three possibilities, which are, roughly:
1. Add a textbox to MainForm, set its control source to '= Subform1.ID', link Subform2.Subform1ID to this field as child to parent, and make MainForm recalculate every time Subform1 moves record.
2. Set Subform2's filter property to '= Subform2.Subform1ID = Forms.MainForm.Subform1.Form.ID' (or whatever the correct syntax would be), and make Subform2 recalculate every time Subform1 moves record.
3. Use 'Forms.Mainform.Subform1.Form.ID' (ditto on the syntax) in the criteria for the Subform1ID field in Subform2's record source query, and make Subform2 requery every time Subform1 moves record.