help writing a layout

hello all !

i need to write 2 layouts:

1) a layout with a square in the middle that changes the color in the square during the application, where there are 10 different colors and i change to tje right color when needed.

2) a layout to represent a point(x,y) in a 2-dimension space(XY), when the (0,0) is in the middle of the screen and
i can put for example a red point in (1,1).

I really need help immediately in both of the layers, if you know how to implement only one of them it can also help me.

TX a lot

Ben