Example Button API

local nButtons = 3 --The number of buttons
local nMaxButtonText = 10 --The fake maximum text length

term.setBackgroundColor(colors.black)
term.clear()

local nPadding = 1

local termX, termY = term.getSize()
local nMaxButtonLength = nMaxButtonText + (nPadding*2)

local nButtonDistance = (termX-(nMaxButtonLength*nButtons))/(nButtons-1)
nButtonDistance = math.floor(nButtonDistance)

local function drawButton(x,y)
    term.setCursorPos(x,y)
    term.write(string.rep(" ",nMaxButtonText))
end


term.setBackgroundColor(colors.blue)
local xCoord = 1
for index=1,nButtons do
    drawButton(xCoord, 5)
    xCoord = xCoord + nMaxButtonLength + nButtonDistance
end