Drawing App of Sorts, help with moving objects relative to others and show alignments

[scooter133]

I'm working on a Drawing app of sorts and want to move 'Screen Elements' around the screen but I want to be able to align the edges, center with other objects on the screen, Similar to Interface Builder.

I have my Screen Elements, that for now just programatically drawn on the screen. I can move them around too.

Though I'm not sure how To check my position relative to the other Screen Elements. Seems like There needs to be an Object that Owns all of my Screen Elements and Manages the movements of the objects. So it could do the drawing of the alignment ligns and the snapping to edges, etc.

A Sample App that does this would be super.

Though I's settle for some concepts on how it should be done too.

Thanks