Hello,
These are two editable grids . When I press edit link in above grid , then below grid named "Users PArt of Group" should be displayed.
How to do that using recordaction field
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Make Grid selectable, then save that selected value in local variable, (In your case just put a visibility condition a!isnotnullorempty(Local!v1), if u want that data in below grid (in grid give that local variable))