Work with the Collection Items
The click events of the two buttons to move the child forms to right and left use two different ways of working with items in a collection.
The click event of the Move all Form Bs Right button invokes a MoveRight method of Form B for all forms in the collection:
Invoke Method(#formBs<>.MoveRight)
To work with all items in the collection specify a blank key for the collection:
#CollectionName<>
The click event of the Move all Form Bs Left uses a For/EndFor loop to iterate through the items in the collection and to move them to the left:
For Each(#Current) In(#FormBs)
Change Field(#NEW_LEFT) To('#Current.Left - 5')
Set Com(#Current) Left(#New_Left)
Endfor
Also see