DComboBox with icons

comboboxicons.lua

local PANEL = {}

function PANEL:Init()
    self.Icons = {}
    self.IconMaterials = {}
end

function PANEL:SetText(value)
    -- add some space for the icon
    -- this is really not rigorous
    self.BaseClass.SetText(self, "     " .. value)
end

function PANEL:AddChoice(value, icon, data, select)
    local choiceIndex = self.BaseClass.AddChoice(self, value, data, select)
    self.Icons[choiceIndex] = icon or false
    self.IconMaterials[choiceIndex] = icon and Material(icon) or false
    return choiceIndex
end

function PANEL:PaintOver(w, h)
    local selected = self:GetSelectedID()
    local icon = self.IconMaterials[selected]
    if not icon then return end
    local iconSize = 16
    local padding = h/2 - iconSize/2
    surface.SetDrawColor(color_white)
    surface.SetMaterial(icon)
    surface.DrawTexturedRect(padding, padding, iconSize, iconSize)
end

function PANEL:OpenMenu()
    self.BaseClass.OpenMenu(self)
    local items = self.Menu:GetCanvas():GetChildren()
    for index, item in ipairs(items) do
        local icon = self.Icons[index]
        if not icon then continue end
        item:SetIcon(icon)
    end
end

vgui.Register("DComboBoxIcons", PANEL, "DComboBox")


local function test()

    local frame = vgui.Create("DFrame")
    frame:SetSize(400, 200)

    local comboBox = vgui.Create("DComboBoxIcons", frame)
    comboBox:SetPos(20, 30)
    comboBox:SetSize(100, 25)
    
    comboBox:AddChoice("Test", "icon16/user.png")
    comboBox:AddChoice("Test 2", "icon16/lightning.png")

    comboBox:ChooseOptionID(1)

    frame:MakePopup()

end 
concommand.Add("testp", test)