Game Manager

Inventory System

Track multiple item types in a single component. Each slot has its own name, icon, capacity, and events — call Increment("Keys") or Increment(0) from any trigger. Optional card UI generates automatically.

Multiple item types in one component

Per-slot full, empty, and change events

Icon card UI row (auto-generated)

Persists between scenes

Combination check — fire an event when multiple items are collected

Choosing the right manager

Inventory vs Collection

They look similar but serve different purposes.

GameInventoryManager — use when you have multiple item types

Keys, arrows, potions, gems — different things that need to be tracked separately. Each slot has its own name, icon, max capacity, and full/empty events. Increment("Keys") only adds to the Keys slot.

GameCollectionManager — use for a single score or currency

One number with threshold events — coins collected, score, lives. Simpler setup. Also used as the currency source for GameStoreManager. If you only need one number, use this.

Getting started

Minimal setup

1

Add GameInventoryManager to a GameObject

Create an empty "Managers" object and add the component. By default it starts with one slot named "Item".
2

Configure your slots

Expand Inventory Slots. For each item type: set Item Name, Max Capacity, and optionally a Sprite Icon. Add more slots with the + button. Use names you'll remember — you can call Increment("Keys") by name.
3

Wire pickups to Increment

On each collectible, add an InputTriggerZone with tag Player. Wire On Enter → GameInventoryManager.Increment(0) (slot index) or IncrementByName("Keys"). Then disable or destroy the collectible in the same event.
4

(Optional) Enable Show UI

Check Show UI for a row of icon cards — one per slot — automatically created at runtime. Each card shows the icon and current count. Position the row with UI Position and adjust card size and spacing.

Configuration

Slot fields and events

Slot Field	Default	What it does
Item Name	Item	The name used by `IncrementByName()` and `DecrementByName()`. Make it unique and descriptive ("Keys", "Arrows", "Potions").
Icon	none	Sprite shown in the UI card when Show UI is enabled.
Max Capacity	10	Increment stops at this value. onFull fires when the count reaches it.
Current Count	0	Starting count for this slot. Can be set above 0 to start with items.
onFull	—	Fires once when the count reaches Max Capacity. Wire to a "slot full" effect.
onEmpty	—	Fires once when the count drops to zero. Wire to a "out of ammo" or "no keys" response.
onChanged	—	Fires on every count change, passing the new count (int) as a parameter. Wire to a custom text display.

💡

Initial events fire on Start

On scene load, all slots fire onChanged with their starting count. This means any external text display wired to onChanged will show the correct value immediately without any extra setup.

Calling from UnityEvents

Public methods

All methods are callable from UnityEvents. Use the by-name versions — they're easier to read and still work correctly if you reorder slots later.

By index

Slot 0 = first slot in the list

Add itemIncrement(0, 1)

Remove itemDecrement(0, 1)

Use if availableUseItem(0, 1)

Read countGetCount(0)

By name

Matches Item Name in the slot config

Add itemIncrementByName("Keys")

Remove itemDecrementByName("Keys")

Read countGetCountByName("Keys")

Logs a warning in Console if no slot with that name exists.

🔑

UseItem — consume only if you have enough

UseItem(0, 1) calls Decrement only if currentCount >= amount. It does nothing if the slot is empty — perfect for door locks that should only open when the player actually has a key. Use it anywhere a "can I afford this?" check is needed.

Multi-item unlock

Combination Check

Fire an event the moment a player holds the right combination of items simultaneously — no extra components needed. Define the required counts in the Combination Check section and wire On Combination Met to any response.

1

Add requirements

In the Combination Check section, click + to add requirements. Each entry has an Item Name (must match a slot's Item Name exactly) and a Required Count.
2

Wire On Combination Met

The On Combination Met event appears once you add at least one requirement. Wire it to whatever should happen — unlock a door, trigger a cutscene, load the next scene.
3

Play — it fires automatically

No extra scripting needed. The manager checks the combination after every Increment or Decrement and fires the event the first time all requirements are met.

Example — unlock the boss door

Requires 3 keys and 1 sword

Requirement 1Keys → 3

Requirement 2Sword → 1

On Combination MetDoor.SetActive(false)

Example — craft a potion

Consume ingredients, spawn result

Requirement 1Herbs → 2

Requirement 2Water → 1

On Combination MetActionSpawnObject.Spawn

🔁

Re-fires if broken and re-met

The event fires once each time the combination transitions from not met to met. If the player spends items (breaking the combination) and then re-collects enough, it fires again. Collecting extras beyond the requirement does not re-fire the event.

Inspector reference

Manager-level fields

Field	Default	What it does
Persist Across Scenes	false	Carries slot counts when loading a new scene. Limited to the first 20 slots.
On Restart	Reset To Default	When RestartScene() is called: Reset To Default clears counts; Keep Value preserves them.
Show UI	false	Creates a row of icon + count cards at runtime. One card per slot, laid out left to right.
Show Count	true	Shows the numeric count inside each card. Uncheck for icon-only display (e.g. key slots where you just want to see the icon).
UI Position	(60, -120)	Top-left origin screen position for the first card. Cards extend to the right.
Card Size	(70, 70)	Width and height of each card in pixels (at 1920×1080).
Card Spacing	8	Gap in pixels between cards.
Requirements	empty	List of item + count pairs for the combination check. Each entry's Item Name must match a slot's Item Name exactly.
onCombinationMet	—	Fires when every requirement in the list is satisfied simultaneously. Only appears in the Inspector when at least one requirement is defined.