--handle already existing filters
            if(currentFilter) then
                result = result and currentFilter(slot)
            end

function(slot)                              
            local result = true                     
            for _,v in pairs(filters[filterType]) do
                if(v) then                          
                    result = result and v(slot)     
                end                                 
            end                                     
            return result                           
        end

-- in libfilters.lua
-- this should be local 
filters = libFilters.filters

ITEMFILTERTYPE_ALL
ITEMFILTERTYPE_WEAPONS
ITEMFILTERTYPE_ARMOR
ITEMFILTERTYPE_CONSUMABLE
ITEMFILTERTYPE_CRAFTING
ITEMFILTERTYPE_MISCELLANEOUS
ITEMFILTERTYPE_JUNK

local ITEMFILTERTYPE_FCOLOCKED = 137  -- whatever unique number

PLAYER_INVENTORY:ChangeFilter(tabData)

PLAYER_INVENTORY:RefreshAllInventorySlots(iInventory)

local tSlots = PLAYER_INVENTORY.inventories[iInventory].slots
    if not tSlot then 
        PLAYER_INVENTORY:RefreshAllInventorySlots(iInventory)
        tSlots   = PLAYER_INVENTORY.inventories[iInventory].slots
    end

local updateSet = false

-- This line
updateSet = false
-- before calling this line
UpdateFilteredList(filterType)

-- in libfilters.lua
-- this should be local
filters = libFilters.filters

result = result and <something else>

for _,v in pairs(filters[filterType]) do
   if(v) then
      result = result and v(slot)
   end
end

for _,v in pairs(filters[filterType]) do
   result = result and v(slot)
   if result == false then
      return result
   end
end

function(slot)
    for _,v in pairs(filters[filterType]) do
        if not v(slot) then
            return false
        end
    end
    return true
end

--Choose the filter type
local function getSettingsIsFilterOn(p_filterId, p_filterPanel)

if (controlId==1 and parent:GetParent() == ZO_ListDialog1ListContents) then
 
            --Pre-Hook the handler for mouse button up, to show context menu at mouse button 2, but keep the normal OnMouseUp handler as well
            --parent:SetHandler("OnMouseUp", function(control, button, upInside)
            --PreHookHandler( "OnMouseUp", parent, function(control, button, upInside)
            ZO_PreHookHandler(parent, "OnMouseUp", function(control, button, upInside)
                --d("Clicked: " ..control:GetName() .. ", MouseButton: " .. tostring(button))
                --button 1= left mouse button / 2= right mouse button
                if button == 2 and upInside then
                    --Add the menu items to the popup dialog row (parent)
                    ClearMenu()
                    for i = 1, gFCONumFilterIcons, 1 do
                        zo_callLater(function() AddMark(parent, i, false) end, 50)
                    end
                end
            end)
        end

--Check the weapon type of a weapon
local function checkWeaponType(p_weaponType, p_check)
d(colorDrkOrange.."checkWeaponType")
    if (p_check == nil or p_check == '') then
        p_check = '1hd'
    end
    if (p_weaponType ~= nil) then
 
        if     (p_check == '1hd') then
 
            if (p_weaponType == WEAPONTYPE_AXE or
                p_weaponType == WEAPONTYPE_DAGGER or
                p_weaponType == WEAPONTYPE_HAMMER or
                p_weaponType == WEAPONTYPE_SWORD) then
                return true
            end
-- exc....more code, lots of elseif statements --

local p_Check_table = {
   ["1hd"] = {
      [WEAPONTYPE_AXE] = true,
      [WEAPONTYPE_DAGGER] = true,
      [WEAPONTYPE_HAMMER] = true,
      [WEAPONTYPE_SWORD] = true,
   },
--- exc...do this for all of the p_check types
   }
}
-- then do something like:
local function checkWeaponType(p_weaponType, p_check)
   -- ... code ... --
   if (p_weaponType ~= nil) then
      if p_Check_table[p_check] and p_Check_table[p_check][p_weaponType] then
         return true
      end
   end
--.. was there more code? I'm getting to lazy to go back and look.. if so do it too.. --
   return false
end

if (    rowControl:GetParent() ~= ZO_StoreWindowListContents
        and rowControl:GetParent() ~= ZO_BuyBackListContents
        and rowControl:GetParent() ~= ZO_PlayerInventoryQuestContents
        --and rowControl:GetParent() ~= ZO_SmithingTopLevelImprovementPanelInventoryBackpackContents
        and rowControl:GetParent() ~= ZO_SmithingTopLevelImprovementPanel
        and rowControl:GetParent() ~= ZO_SmithingTopLevelResearchPanelResearchLineListList
        and rowControl:GetParent() ~= ZO_SmithingTopLevelCreationPanelPatternListList
        and rowControl:GetParent() ~= ZO_SmithingTopLevelCreationPanelMaterialListList
        and rowControl:GetParent() ~= ZO_SmithingTopLevelCreationPanelStyleListList
        and rowControl:GetParent() ~= ZO_SmithingTopLevelCreationPanelTraitListList
        and rowControl:GetParent() ~= ZO_AlchemyTopLevelInventoryBackpackContents
        and rowControl             ~= ZO_AlchemyTopLevelSlotContainer
        --and rowControl:GetParent() ~= ZO_EnchantingTopLevelInventoryBackpackContents
        and rowControl             ~= ZO_EnchantingTopLevelRuneSlotContainer
        and rowControl             ~= ZO_EnchantingTopLevelExtractionSlotContainer
        and rowControl:GetParent() ~= ZO_MailInboxMessage
        and rowControl:GetParent() ~= ZO_MailSend
        and rowControl             ~= ZO_ApplyEnchantPanel
        and rowControl             ~= ZO_SoulGemItemChargerPanel
        and rowControl:GetParent() ~= ZO_QuickSlotListContents) then

local parent = rowControl:GetParent() 
    --Check if the right click menu should be updated. Only allowed panels and menus apply
    if (    parent ~= ZO_StoreWindowListContents
        and parent ~= ZO_BuyBackListContents
        and parent ~= ZO_PlayerInventoryQuestContents
        --and parent ~= ZO_SmithingTopLevelImprovementPanelInventoryBackpackContents
        and parent ~= ZO_SmithingTopLevelImprovementPanel
        and parent ~= ZO_SmithingTopLevelResearchPanelResearchLineListList
        and parent ~= ZO_SmithingTopLevelCreationPanelPatternListList
        and parent ~= ZO_SmithingTopLevelCreationPanelMaterialListList
        and parent ~= ZO_SmithingTopLevelCreationPanelStyleListList
        and parent ~= ZO_SmithingTopLevelCreationPanelTraitListList
        and parent ~= ZO_AlchemyTopLevelInventoryBackpackContents
        and rowControl             ~= ZO_AlchemyTopLevelSlotContainer
        --and parent ~= ZO_EnchantingTopLevelInventoryBackpackContents
        and rowControl             ~= ZO_EnchantingTopLevelRuneSlotContainer
        and rowControl             ~= ZO_EnchantingTopLevelExtractionSlotContainer
        and parent ~= ZO_MailInboxMessage
        and parent ~= ZO_MailSend
        and rowControl             ~= ZO_ApplyEnchantPanel
        and rowControl             ~= ZO_SoulGemItemChargerPanel
        and parent ~= ZO_QuickSlotListContents) then

local tAllowedPanels = {
   ["AlchemyTopLevelInventoryBackpackContents"] = true,
   ["SmithingTopLevelCreationPanelTraitListList"]     = true,
   ["SmithingTopLevelResearchPanelResearchLineListList"] = true,
-- exc...--
}

-- instead of doing this
--local parent = rowControl:GetParent() 
-- and that big if statement
 
-- you could just do this
local parentName = rowControl:GetParent():GetName()
if tAllowedPanels[parentName] then
-- do whatever --
end

if (settings.autoMarkAllWeapon == false) then
   if (    rowControl:GetName() == 'ZO_CharacterEquipmentSlotsMainHand'
   or rowControl:GetName() == 'ZO_CharacterEquipmentSlotsOffHand'
   -- lots more rowControl:GetName()

local function UpdatePlayerInventory()
---...code...---
-- It calls: 
PLAYER_INVENTORY:UpdateList(1)

-- replace
for slotIndex = 1, GetBagSize(bagId) do
-- with
for slotIndex = 0, GetBagSize(bagId) - 1 do

-- You register for this:
EVENT_MANAGER:RegisterForEvent(gAddonName, EVENT_INVENTORY_SINGLE_SLOT_UPDATE, FCOItemSaver_Inv_Update)
 
-- then in it you zo_calllater this:
--scanInventory(bagId, slotId)

function FCOItemSaver_Inv_Update( eventCode, bagId, slotId, isNewItem, itemSoundCategory, updateReason )
    if GetItemType(bagId, slotId) == ITEMTYPE_NONE then return end

zo_callLater(function()
                debugMessage("Event 'Single inventory slot updated' executed now! bagId=" .. bagId .. ", slotIndex=" .. slotId, true)
                scanInventory(bagId, slotId)
            end, 250)

--Automatic marking of ornate and/or researchable items (researchAssistant addon needed!) is activated?

markedItems[3][itemId] = true

--Inventory slot gets updated function
function FCOItemSaver_Inv_Update( eventCode, bagId, slotId, isNewItem, itemSoundCategory, updateReason )
    if not isNewItem and bagId ~= BAG_BACKPACK then return end
    if  GetItemType(bagId, slotId) == ITEMTYPE_NONE then return end
    
    scanInventory(bagId, slotId)
end

--Scan the inventory for ornate and/or researchable items
local function scanInventory(p_bagId, p_slotIndex)

--Update ornate items
CheckForOrnate(bagId, slotId, any other info needed....)  
-- and
--Update researchable items
CheckForResearchable(bagId, slotId, any other info needed....)

if bagId =~ BAG_BACKPACK then return end

-- You do \have to include the library file in your .txt file, see instructions on my portal page for libItemInfo
 
--Put this line at the top of your code file to register the library
local LII = LibStub:GetLibrary("LibItemInfo-1.0")
 
 
-- Then Call this function & pass in either a link
LII:NeedForResearch(Link)
 
-- or a bagId & slotId, it will work either way, that's it.
LII:NeedForResearch(BagId, SlotId)

-- You do \have to include the library file in your .txt file, see instructions on my portal page for libItemInfo
 
--Put this line at the top of your code file to register the library
local LII = LibStub:GetLibrary("LibItemInfo-1.0")
 
 
-- Then Call this function & pass in either a link
LII:NeedForResearch(Link)
 
-- or a bagId & slotId, it will work either way, that's it.
LII:NeedForResearch(BagId, SlotId)

local BACKPACK                  = ZO_PlayerInventoryBackpack
local BANK                      = ZO_PlayerBankBackpack
local GUILD_BANK                = ZO_GuildBankBackpack
local DECONSTRUCTION            = ZO_SmithingTopLevelDeconstructionPanelInventoryBackpack
local IMPROVEMENT               = ZO_SmithingTopLevelImprovementPanelInventoryBackpack
local MAIL_SEND                 = ZO_MailSend
local PLAYER_TRADING            = ZO_Trade
local ENCHANTING_STATION        = ZO_EnchantingTopLevelInventoryBackpack
local VENDOR_SELL             = ZO_StoreWindowListSellToVendorArea

--See if we are sending a mail
    if (not MAIL_SEND:IsHidden()) then
        -- register additional filter for LAF_MAIL
       elseif (not PLAYER_TRADING:IsHidden()) then 
        -- register additional filter for LAF_TRADE
       ...
      end

local function SetUpCallbackFilter( self, filterTag )
    local inventoryType = GetCurrentInventoryType()
    local laf = libFilters:GetCurrentLAF(inventoryType)

LAF_IMPROVEMENT = 13

--LAF_IMPROVEMENT
libFilters.filters = {
    [LAF_BAGS] = {},
    [LAF_BANK] = {},
    [LAF_GUILDBANK] = {},
    [LAF_STORE] = {},
    [LAF_DECONSTRUCTION] = {},
    [LAF_GUILDSTORE] = {},
    [LAF_MAIL] = {},
    [LAF_TRADE] = {},
    [LAF_ENCHANTING_CREATION] = {},
    [LAF_ENCHANTING_EXTRACTION] = {},
    [LAF_IMPROVEMENT] = {},
}
 
--this one doesn't set the filter, but it IS the filter
--since this is a PreHook using ZO_PreHook, a return of true means don't add
local function ImprovementFilter( self, bagId, slotIndex, ... )
    return not runFilters(LAF_IMPROVEMENT, bagId, slotIndex)
end
 
 
local inventoryUpdaters = {
    BACKPACK = function()
        PLAYER_INVENTORY:UpdateList(INVENTORY_BACKPACK)
    end,
    BANK = function()
        PLAYER_INVENTORY:UpdateList(INVENTORY_BANK)
    end,
    GUILD_BANK = function()
        PLAYER_INVENTORY:UpdateList(INVENTORY_GUILD_BANK)
    end,
    DECONSTRUCTION = function()
        SMITHING.deconstructionPanel.inventory:HandleDirtyEvent()
    end,
        IMPROVEMENT = function()
                SMITHING.improvementPanel.inventory:HandleDirtyEvent()
        end,
    ENCHANTING = function()
        ENCHANTING.inventory:HandleDirtyEvent()
    end,
}
 
local filterTypeToUpdaterName = {
    [LAF_BAGS] = "BACKPACK",
    [LAF_BANK] = "BANK",
    [LAF_GUILDBANK] = "GUILD_BANK",
    [LAF_STORE] = "BACKPACK",
    [LAF_DECONSTRUCTION] = "DECONSTRUCTION",
    [LAF_GUILDSTORE] = "BACKPACK",
    [LAF_MAIL] = "BACKPACK",
    [LAF_TRADE] = "BACKPACK",
    [LAF_ENCHANTING_CREATION] = "ENCHANTING",
    [LAF_ENCHANTING_EXTRACTION] = "ENCHANTING",
        [LAF_IMPROVEMENT] = "IMPROVEMENT",
}
 
unction libFilters:InitializeLibFilters()
    if self.IS_INITIALIZED then return end
    self.IS_INITIALIZED = true
 
    -- PLAYER_INVENTORY.inventories[INVENTORY_BACKPACK].additionalFilter
    -- is reset every time a different backpack layout fragment is shown,
    -- therefore it needs to be hooked in each fragment's layout data
    hookAdditionalFilter(LAF_BAGS, BACKPACK_MENU_BAR_LAYOUT_FRAGMENT)
    hookAdditionalFilter(LAF_BAGS --[[ correct, not LAF_BANK ]], BACKPACK_BANK_LAYOUT_FRAGMENT)
    hookAdditionalFilter(LAF_STORE, BACKPACK_STORE_LAYOUT_FRAGMENT)
    hookAdditionalFilter(LAF_GUILDSTORE, BACKPACK_TRADING_HOUSE_LAYOUT_FRAGMENT)
    hookAdditionalFilter(LAF_MAIL, BACKPACK_MAIL_LAYOUT_FRAGMENT)
    hookAdditionalFilter(LAF_TRADE, BACKPACK_PLAYER_TRADE_LAYOUT_FRAGMENT)
 
    -- other inventories seem to never reset additionalFilter
    hookAdditionalFilter(LAF_BANK, PLAYER_INVENTORY.inventories[INVENTORY_BANK])
    hookAdditionalFilter(LAF_GUILDBANK, PLAYER_INVENTORY.inventories[INVENTORY_GUILD_BANK])
 
    ZO_PreHook(SMITHING.deconstructionPanel.inventory, "AddItemData", DeconstructionFilter)
        ZO_PreHook(SMITHING.improvementPanel.inventory, "AddItemData", ImprovementFilter)  
    ZO_PreHook(ENCHANTING.inventory, "AddItemData", EnchantingFilter)
end

function GetCurrentInventoryType()
    return g_currentInventoryType
end

Inventory:
 1. /zgoo GetCurrentInventoryType() -> INVENTORY_BACKPACK
 2. /zgoo PLAYER_INVENTORY.appliedLayout.libFilters_filterType -> LAF_BAGS
 3. /zgoo PLAYER_INVENTORY.inventories[GetCurrentInventoryType()].libFilters_filterType -> LAF_BAGS

PLAYER_INVENTORY:UpdateList(INVENTORY_BACKPACK)

function ZO_SharedCraftingInventory:HandleDirtyEvent()
    if self.control:IsHidden() or ZO_CraftingUtils_IsPerformingCraftProcess() then
        self.dirty = true
    else
        self:PerformFullRefresh()
    end
end

function ZO_Smithing:SetMode(mode)
    if self.mode ~= mode then
        self.mode = mode
 
        CRAFTING_RESULTS:SetCraftingTooltip(nil)
        self.refinementPanel:SetHidden(mode ~= SMITHING_MODE_REFINMENT)
        self.creationPanel:SetHidden(mode ~= SMITHING_MODE_CREATION)
        self.improvementPanel:SetHidden(mode ~= SMITHING_MODE_IMPROVEMENT)
        self.deconstructionPanel:SetHidden(mode ~= SMITHING_MODE_DECONSTRUCTION)
        self.researchPanel:SetHidden(mode ~= SMITHING_MODE_RESEARCH)
 
        KEYBIND_STRIP:UpdateKeybindButtonGroup(self.keybindStripDescriptor)
        TriggerTutorial(self.GetTutorialTrigger(self, GetCraftingInteractionType(), mode))
    end
end