View difference between Paste ID: sxJqfjAa and RK2HJPPh

 os.loadAPI("/rom/apis/colors")
 
 --[[ Variables ]]--
 local offset = 0
 local sel = 1
 local printThanks = false
 local buffer = {}
 
 local bgColour, textColour, selectedBgColour, selectedTextColour
 
 if term.isColour() then
  bgColour = colors.white
  textColour = colors.gray
  selectedBgColour = colors.lightBlue
  selectedTextColour = colors.white
 else
  bgColour = colors.white
  textColour = colors.black
  selectedBgColour = colors.black
  selectedTextColour = colors.white
 end
 
 local maxX, maxY = term.getSize()
 local running
 
 --[[ Functions ]]--
 
 clear = function()
  term.clear()
  term.setCursorPos(1,1)
 end
 
 local function centerWrite(txt)
  local x, y = term.getCursorPos()
  term.setCursorPos(math.floor(maxX/2-#tostring(txt)/2),y)
  write(txt)
 end
 
 local function redraw(tbl, sel, offset)
  term.setBackgroundColour(bgColour)
  clear()
  for i=1, maxY do
   if tbl[i] ~= nil then
    term.setCursorPos(1, i)
    if (i+offset) == sel then
     term.setBackgroundColour(selectedBgColour)
     term.clearLine()
     term.setTextColour(selectedTextColour)
     centerWrite("[ "..tbl[i + offset].text.." ]")
    else
     term.setBackgroundColour(bgColour)
     term.clearLine()
     term.setTextColour(textColour)
     centerWrite(tbl[i + offset].text)
    end
   end
  end
 end
 
 local function checkTable(tbl)
  for i,v in ipairs(tbl) do
   if v.handler == nil or type(v.handler) ~= "function" then
    if term.isColour() then
     term.setTextColour(colors.red)
    end
    print("Menu item \""..i.."\" has no valid handler!")
    local txt = textutils.serialize(tostring(v.handler))
    error("handler = "..txt, 0)
   elseif v.text == nil then
    if term.isColour() then
     term.setTextColour(colors.red)
    end
    print("Menu item \""..i.."\" has no text!")
    local txt = textutils.serialize(tostring(v.text))
    error("text = "..txt, 0)
   end
  end
 end
 
 runMenu = function(tbl)
  if type(tbl) ~= "table" then
   error("Invalid arguments!\nUsage: menuApi.runMenu(menu_table)", 0)
  elseif #tbl < 2 then
   error("Not enough items in menu!\nAt least 2 items are required!", 0)
  end
 
  checkTable(tbl)
 
  offset = 0
  running = true
  while running do
   if sel > #tbl then sel = #tbl end
   term.setCursorBlink(false)
   os.queueEvent("")
   os.pullEvent()
   redraw(tbl, sel, offset)
   local ev = {os.pullEvent()}
   if ev[1] == "key" then
    if ev[2] == keys.up then
     if sel > 1 then sel = sel - 1 end
     if offset > 0 then offset = offset - 1 end
    elseif ev[2] == keys.down then
     if sel < #tbl then sel = sel + 1 end
     if offset < math.max(#tbl - maxY, 0) then offset = offset + 1 end
    elseif ev[2] == keys.enter then
     term.setBackgroundColour(colors.black)
     term.setTextColour(colors.white)
     clear()
     tbl[sel].handler()
    end
   elseif ev[1] == "mouse_scroll" then
    if ev[2] == -1 then
     if sel > 1 then sel = sel - 1 end
     if offset > 0 then offset = offset - 1 end
    elseif ev[2] == 1 then
     if sel < #tbl then sel = sel + 1 end
     if offset < math.max(#tbl - maxY, 0) then offset = offset + 1 end
    end
   elseif ev[1] == "mouse_click" then
    if tbl[(ev[4] + offset)] ~= nil then
     sel = ev[4] + offset
     redraw(tbl, sel, offset)
     sleep(.1)
     term.setBackgroundColour(colors.black)
     term.setTextColour(colors.white)
     clear()
     tbl[(ev[4] + offset)].handler()
    end
   end
  end
 end
 
 stopMenu = function()
  running = false
  term.setBackgroundColour(colors.black)
  if printThanks == true then
   if term.isColour() == true then
    term.setTextColour(colors.yellow)
   end
   clear()
   centerWrite("Thank you for using HD's menu api.")
   print("")
  else
   clear()
  end
 end
 
 listMethods = function()
  local tmp = {}
  for i,v in pairs(menu) do
   table.insert(tmp, i.."()")
  end
  textutils.pagedTabulate(tmp)
  local tmp = nil
 end
 
 local function isColour(color)
  if term.isColour() then
   if type(color) == "string" then
    if colors[color] ~= nil then
     return {true, colors[color]}
    else
     return false
    end
   elseif type(color) == "number" then
    if color >= 1 and color <= colors.black then
     return {true, color}
    else
     return false
    end
   else
    return false
   end
  else
   return false
  end
 end
 
 setBackgroundColour = function(color)
  local tmp = isColour(color)
  if tmp[1] then
   bgColour = tmp[2]
  end
 end
 
 setBarColour = function(color)
  local tmp = isColour(color)
  if tmp[1] then
   selectedBgColour = tmp[2]
  end
 end
 
 setTextColour = function(color)
  local tmp = isColour(color)
  if tmp[1] then
   textColour = tmp[2]
  end
 end
 
 setBarTextColour = function(color)
  local tmp = isColour(color)
  if tmp[1] then
   selectedTextColour = tmp[2]
  end
 end
 
 setBarTextColor = setBarTextColour
 setTextColor = setTextColour
 setBarColor = setBarColour
 setBackgroundColor = setBackgroundColour
 
 saveMenu = function(tbl, name)
  if tbl == nil or type(tbl) ~= "table" then
   error("Argument 1 must be table!", 0)
  elseif name == nil or type(name) ~= "string" then
   error("Argument 2 must be string!")
  end
 
  buffer[name] = tbl
 end
 
 loadMenu = function(name)
  if name == nil or type(name) ~= "string" then
   error("Argument invalid!\nname is not a string or nil!")
  end
 
  if buffer[name] == nil then
   error("Menu '" .. name .. "' does not exist!", 0)
  else
   runMenu(buffer[name])
  end
 end