Moving two Rect in Sync with each other

1

I have two rectangles “A” and “B”

I want to move “A” and have “B” track along with it.

So if “C” is the new position of “A” then I thought it would be

newPos = (b.x-a.x) // how far b is from left edge of "a"
newPos = newPos + c.x // offset same distance from left edge of "C"
b.x=newPos
a.x=c.x

but b.x changes way faster than then “B” moves

2

What about:

deltaX = c.x - a.x
b.x = b.x + deltaX
a.x = c.x
3

I think I may have found it…
the value of “A” is supposed to be "where it was before I moved it to “C”)
but is seems that isn’t always the case… so I’m going to try something differne to track the delta between “A” and “C”

thanks

4

turns out the mousedrag event was propagating too far up the responder chain cause the sync event to be called out of seqeunce…