[Benalish]

The original code was

local function SetWidgetScript(frame,method)
    if frame:IsShown() then
        for i = 1, #frame.buttons do
            frame.buttons[i]:HookScript("OnMouseDown", method)
        end
    else
        frame:SetScript(
            "OnShow", function()
                 for i = 1, #frame.buttons do
                     frame.buttons[i]:HookScript("OnMouseDown", method)
                 end
            end
        )
    end
end

I changed the method in the "OnShow" script just to not repeat the for i=1...end part twice.
There is probably a better way to write a DRY script.