Class PlayerInventoryItemChangeAfterEvent

Example: inventoryChangeListener.ts

import {
    world,
    PlayerInventoryItemChangeAfterEvent,
    InventoryItemEventOptions,
    PlayerInventoryType,
} from "@minecraft/server";

// Example of handling player inventory item change events
function setupInventoryChangeListener() {
    // Basic event subscription - monitor all inventory changes
    world.afterEvents.playerInventoryItemChange.subscribe(
        (event: PlayerInventoryItemChangeAfterEvent) => {
            console.log(`${event.player.name} inventory changed:`);
            console.log(`Slot: ${event.slot} in ${event.inventoryType}`);

            if (event.beforeItemStack) {
                console.log(
                    `Previous item: ${event.beforeItemStack.typeId} (${event.beforeItemStack.amount})`,
                );
            } else {
                console.log("Previous: empty slot");
            }

            if (event.itemStack) {
                console.log(
                    `New item: ${event.itemStack.typeId} (${event.itemStack.amount})`,
                );
            } else {
                console.log("New: empty slot");
            }
        },
    );

    // Subscription with filtering options - monitor specific inventory types and items
    const inventoryOptions: InventoryItemEventOptions = {
        inventoryType: PlayerInventoryType.Hotbar,
        includeItems: [
            "minecraft:diamond_sword",
            "minecraft:bow",
            "minecraft:shield",
        ],
        excludeItems: ["minecraft:dirt", "minecraft:cobblestone"],
        includeTags: ["minecraft:weapons", "minecraft:tools"],
        excludeTags: ["minecraft:building_blocks"],
        ignoreQuantityChange: false, // Track quantity changes
        allowedSlots: [0, 1, 2, 3, 4], // Only monitor first 5 hotbar slots
    };

    world.afterEvents.playerInventoryItemChange.subscribe(
        (event: PlayerInventoryItemChangeAfterEvent) => {
            console.log(`Important inventory change detected!`);
            console.log(`Player: ${event.player.name}`);
            console.log(`Slot ${event.slot} in ${event.inventoryType}`);

            // Check for specific item types
            if (event.itemStack?.typeId === "minecraft:diamond_sword") {
                console.log("Player equipped a diamond sword!");
            } else if (event.itemStack?.typeId === "minecraft:bow") {
                console.log("Player equipped a bow!");
            }

            // Check for item removal
            if (event.beforeItemStack && !event.itemStack) {
                console.log(
                    `Player removed ${event.beforeItemStack.typeId} from slot ${event.slot}`,
                );
            }

            // Check for quantity changes
            if (
                event.beforeItemStack &&
                event.itemStack &&
                event.beforeItemStack.typeId === event.itemStack.typeId
            ) {
                const quantityChange =
                    event.itemStack.amount - event.beforeItemStack.amount;
                if (quantityChange > 0) {
                    console.log(
                        `Player gained ${quantityChange} of ${event.itemStack.typeId}`,
                    );
                } else if (quantityChange < 0) {
                    console.log(
                        `Player lost ${Math.abs(quantityChange)} of ${event.itemStack.typeId}`,
                    );
                }
            }
        },
        inventoryOptions,
    );

    // Example: Monitor only hotbar changes
    const hotbarOnlyOptions: InventoryItemEventOptions = {
        inventoryType: PlayerInventoryType.Hotbar,
    };

    world.afterEvents.playerInventoryItemChange.subscribe(
        (event: PlayerInventoryItemChangeAfterEvent) => {
            console.log(
                `Hotbar change: Player ${event.player.name} slot ${event.slot}`,
            );
        },
        hotbarOnlyOptions,
    );
}

// Call this function to set up the event listeners
setupInventoryChangeListener();
Copy