Refreshing a frame?

[Bombshelly]

I'm trying to write a routine that makes a simple box on the screen. Based on a conditional statement, I would like to change the background color of the box and have it refresh.

I have everything written and it makes sense, except for the "refresh" part. I can't find how to do this. Can anyone lend a hand? Here's a few of the pieces, and thanks in advance!

local context=UI.CreateContext("myWindowFrame")
local bigBox = UI.CreateFrame("Text", "placeHolder", context)

bigBox:SetWidth(20)
bigBox:SetHeight(20)
bigBox:SetPoint("TOPCENTER", UIParent, "TOPCENTER",0,0)
bigBox:SetBackgroundColor(0,0,0,1)
bigBox:SetVisible(true)

local box1 = UI.CreateFrame("Text", "box1", bigBox)
box1:SetWidth(10)
box1:SetHeight(10)
box1:SetPoint("TOPLEFT", bigBox, "TOPLEFT",0,0)
--box1:SetBackgroundColor(1,0,0,1)
box1:SetVisible(true)

--the conditional will call this:
function changemyColor(myC)
	if myC == "whatever" then
                box1:SetBackgroundColor(1,0,0,1)
                --How do I trigger a refresh of my little box after this?
        end
end