Container Classified

Based on game build 722832 | Last updated: 2026-04-21

Overview

container_classified is a hidden prefab entity attached to container replicas to handle client-side inventory prediction and UI state synchronization. It is not spawned directly by modders; instead, it is instantiated automatically by the network replication system when a container is observed by a client. This entity maintains a local preview of item slots (_itemspreview) while waiting for server authority updates, ensuring responsive inventory interactions. It exposes methods for querying slot contents, modifying stack sizes locally, and syncing actions to the server via RPC.

Usage example

-- Access via a container's replica classified data (Client side)
local container = inst.replica.container
if container and container.classified then
    local classified = container.classified
    local item = classified:GetItemInSlot(1)
    local has_wood = classified:Has("logs", 1)
    
    -- Check if the container is currently busy syncing
    if not classified:IsBusy() then
        classified:ReceiveItem(some_item, 1)
    end
end

Dependencies & tags

External dependencies:

• containers -- Used for MAXITEMSLOTS constant and slot initialization.

Components used:

• constructionbuilderuidata -- Accessed on ThePlayer to determine construction ingredient slots during item moves.
• inventory -- Replica accessed for active item queries and stack size synchronization.
• container -- Replica accessed for slot acceptance logic and overflow handling.
• stackable -- Replica accessed for stack size, max size, and stacking compatibility checks.

Tags:

• CLASSIFIED -- Added to the entity to identify it as a network classified data holder.

Properties

Property	Type	Default Value	Description
infinitestacksize	net_bool	false	Network variable indicating if the container allows infinite stacking.
readonlycontainer	net_bool	false	Network variable indicating if the container is read-only.
_items	table	{}	Array of net_entity variables representing the authoritative item slots.
_itemspool	table	{}	Pool of unused net_entity variables for slot resizing.
_slottasks	table	nil	Map of pending tasks for specific slot dirty events.
_refreshtask	task	nil	Scheduled task reference for debouncing UI refreshes.
_busy	boolean	true	Flag indicating if the classified data is currently processing a sync.
_itemspreview	table	nil	Temporary table holding proxy items during client prediction before server sync.
_parent	entity	nil	Reference to the parent container entity that owns this classified instance.

Main functions

InitializeSlots(numslots)

• Description: Resizes the _items array to match numslots. Moves entities between _items and _itemspool to adjust capacity.
• Parameters: numslots -- target number of slots.
• Returns: None.
• Error states: Errors if inst._slottasks is not nil (cannot re-initialize after listeners are registered).

SetSlotItem(slot, item, src_pos)

• Description: Server-side function. Sets the item in a specific slot and serializes usage data if valid.
• Parameters:
  • slot -- integer slot index.
  • item -- entity instance or nil.
  • src_pos -- vector position for pickup serialization.
• Returns: None.
• Error states: None.

IsHolding(item, checkcontainer)

• Description: Checks if the container holds item, optionally checking nested containers.
• Parameters:
  • item -- entity instance to check.
  • checkcontainer -- boolean to recurse into contained inventories.
• Returns: true if holding, false otherwise.
• Error states: None.

GetItemInSlot(slot)

• Description: Returns the item entity in the specified slot. Uses preview data if available.
• Parameters: slot -- integer slot index.
• Returns: Entity instance or nil.
• Error states: None.

GetItems()

• Description: Returns a table of all items currently in the container.
• Parameters: None.
• Returns: Table of entity instances.
• Error states: None.

IsEmpty()

• Description: Checks if all slots are empty.
• Parameters: None.
• Returns: true if empty, false otherwise.
• Error states: None.

IsFull()

• Description: Checks if all slots are occupied.
• Parameters: None.
• Returns: true if full, false otherwise.
• Error states: None.

Has(prefab, amount, iscrafting)

• Description: Checks if the container has at least amount of prefab. Optionally excludes items tagged nocrafting.
• Parameters:
  • prefab -- string prefab name.
  • amount -- number required.
  • iscrafting -- boolean to filter crafting-usable items.
• Returns: boolean (has enough), number (actual count found).
• Error states: None.

HasItemWithTag(tag, amount)

• Description: Checks if the container has items with a specific tag totaling amount.
• Parameters:
  • tag -- string tag name.
  • amount -- number required.
• Returns: boolean (has enough), number (actual count found).
• Error states: None.

FindItem(fn)

• Description: Iterates items and returns the first one matching the predicate function fn.
• Parameters: fn -- function(item) returning boolean.
• Returns: Entity instance or nil.
• Error states: None.

ReceiveItem(item, count, forceslot)

• Description: Attempts to add item to the container locally. Handles stacking and slot finding. Returns remainder if not all could be accepted. Silently returns without action if forceslot is out of bounds (guard condition present in source).
• Parameters:
  • item -- entity instance.
  • count -- number of items to add (optional).
  • forceslot -- specific slot index (optional).
• Returns: Number of items remaining (0 if fully accepted).
• Error states: None

ConsumeByName(prefab, amount)

• Description: Removes items matching prefab from the container up to amount. Used for local prediction of crafting costs.
• Parameters:
  • prefab -- string prefab name.
  • amount -- number to remove.
• Returns: None.
• Error states: None.

TakeActionItem(item, slot)

• Description: Removes a specific item from a slot locally.
• Parameters:
  • item -- entity instance.
  • slot -- integer slot index.
• Returns: None.
• Error states: None.

IsBusy()

• Description: Checks if the classified instance is currently processing a refresh or lacks a parent.
• Parameters: None.
• Returns: true if busy, false otherwise.
• Error states: None.

ReturnActiveItemToSlot(slot)

• Description: Moves the player's active item back into the specified slot if valid.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

PutOneOfActiveItemInSlot(slot)

• Description: Moves one unit of the active item into the specified slot and syncs to server.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

PutAllOfActiveItemInSlot(slot)

• Description: Moves the entire active item stack into the specified slot and syncs to server.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

TakeActiveItemFromHalfOfSlot(slot)

• Description: Takes half of a stack from the slot into the active item hand.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

TakeActiveItemFromCountOfSlot(slot, count)

• Description: Takes a specific count from the slot into the active item hand.
• Parameters:
  • slot -- integer slot index.
  • count -- number of items to take.
• Returns: None.
• Error states: None.

TakeActiveItemFromAllOfSlot(slot)

• Description: Takes the entire stack from the slot into the active item hand.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

AddOneOfActiveItemToSlot(slot)

• Description: Adds one unit from the active item to the existing stack in the slot.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

AddAllOfActiveItemToSlot(slot)

• Description: Adds the entire active item stack to the existing stack in the slot.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

SwapActiveItemWithSlot(slot)

• Description: Swaps the active item with the item in the slot.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

SwapOneOfActiveItemWithSlot(slot)

• Description: Swaps one unit of the active item with the item in the slot.
• Parameters: slot -- integer slot index.
• Returns: None.
• Error states: None.

MoveItemFromAllOfSlot(slot, container)

• Description: Moves the entire stack from the slot to another container.
• Parameters:
  • slot -- integer slot index.
  • container -- target container entity.
• Returns: None.
• Error states: None.

MoveItemFromHalfOfSlot(slot, container)

• Description: Moves half the stack from the slot to another container.
• Parameters:
  • slot -- integer slot index.
  • container -- target container entity.
• Returns: None.
• Error states: None.

MoveItemFromCountOfSlot(slot, container, count)

• Description: Moves a specific count from the slot to another container.
• Parameters:
  • slot -- integer slot index.
  • container -- target container entity.
  • count -- number of items to move.
• Returns: None.
• Error states: None.

OnEntityReplicated()

• Description: Called when the entity is replicated. Attaches the classified instance to the parent container's replica.
• Parameters: None.
• Returns: None.
• Error states: Prints error message if parent is nil. Attachment failure does not print an error.

OnRemoveEntity()

• Description: Cleans up references when the entity is removed.
• Parameters: None.
• Returns: None.
• Error states: None.

Events & listeners

• Listens to:
  • items[i]dirty -- Triggered when a specific slot's network variable changes. Queues OnItemsDirty.
  • readonlycontainerdirty -- Triggered when read-only status changes. Queues Refresh.
  • stackitemdirty (TheWorld) -- Triggered when any item stack changes globally. Queues OnStackItemDirty if holding the item.
• Pushes:
  • refresh -- Fired on parent container when local state is synchronized.
  • itemget -- Fired on parent container when an item is added to a slot.
  • itemlose -- Fired on parent container when an item is removed from a slot.
  • stacksizechange -- Fired on item entity when stack size updates.
  • stacksizepreview -- Fired on item entity for client-side stack prediction.
  • refreshcrafting -- Fired on ThePlayer to update crafting UI.
  • cancelrefreshcrafting -- Fired on ThePlayer to debounce crafting updates.
  • gotnewitem -- Fired on ThePlayer when an item is acquired (triggers UI sounds).