1、目标

从库存栏中把道具拖到游戏场景中，库存栏中道具数相应做减法或者删除道具。同时在库存栏中可以交换两个道具的位置。

2、UIInventorySlot设置Raycast属性

在UIInventorySlot中，我们只希望最外层的UIInventorySlot响应Raycast，他下面的2个子对象不需要相应Raycast，所以需要取消InventoryHighlight和Text的Raycast Target设置。

     

3、创建可拖动对象

（1）优化Tags.cs

为了可以方便获取Items对象，新增一个Tag名为ItemsParentTransform，并且将Items标记为ItemsParentTransform。

同时在Assets -> Scripts -> Misc的Tags.cs代码中，新增：

public const string ItemsParentTransform = "ItemsParentTransform";

此时Tags.cs的完整代码是：

using UnityEngine;public static class Tags
{public const string BoundsConfiner = "BoundsConfiner";public const string ItemsParentTransform = "ItemsParentTransform";
}

（2）优化Play.cs

修改Assets -> Scripts -> Player -> Player.cs文件。

当我们用鼠标拖动道具到场景中时，我们不希望角色跟着鼠标移动。

改动1：将已有逻辑移到判断PlayerInputIsDisabled下，当输入不被禁用时才移动。

private void Update()
{#region  Player Inputif (!PlayerInputIsDisabled){ResetAnimationTrigger();PlayerMovementInput();PlayerWalkInput();// Send event to any listeners for player movement inputEventHandler.CallMovementEvent(xInput, yInput, isWalking, isRunning, isIdle, isCarrying, toolEffect,isUsingToolRight, isUsingToolLeft, isUsingToolUp, isUsingToolDown,isLiftingToolRight, isLiftingToolLeft, isLiftingToolUp, isLiftingToolDown,isPickingRight, isPickingLeft, isPickingUp, isPickingDown,isSwingToolRight, isSwingToolLeft, isSwingToolUp, isSwingToolDown,false, false, false, false);}#endregion Player Input
}

改动2：创建禁用/启动输入的函数

 public void DisablePlayerInpupt(){PlayerInputIsDisabled = true;}public void EnablePlayerInput(){PlayerInputIsDisabled = false;}

改动3：对外提供的函数，禁用输入，并且设置用户为静止状态。

public void DisablePlayerInputAndResetMovement()
{DisablePlayerInpupt();ResetMovement();// Send event to any listeners for player movement inputEventHandler.CallMovementEvent(xInput, yInput, isWalking, isRunning, isIdle, isCarrying, toolEffect,isUsingToolRight, isUsingToolLeft, isUsingToolUp, isUsingToolDown,isLiftingToolRight, isLiftingToolLeft, isLiftingToolUp, isLiftingToolDown,isPickingRight, isPickingLeft, isPickingUp, isPickingDown,isSwingToolRight, isSwingToolLeft, isSwingToolUp, isSwingToolDown,false, false, false, false);
}private void ResetMovement()
{// Reset movementxInput = 0f;yInput = 0f;isRunning = false;isWalking = false;isIdle = true;
}

Player.cs完整的代码如下：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class Player : SingletonMonobehaviour<Player>
{private float xInput;private float yInput;private bool isWalking;private bool isRunning;private bool isIdle;private bool isCarrying = false;private ToolEffect toolEffect = ToolEffect.none;private bool isUsingToolRight;private bool isUsingToolLeft;private bool isUsingToolUp;private bool isUsingToolDown;private bool isLiftingToolRight;private bool isLiftingToolLeft;private bool isLiftingToolUp;private bool isLiftingToolDown;private bool isPickingRight;private bool isPickingLeft;private bool isPickingUp;private bool isPickingDown;private bool isSwingToolRight;private bool isSwingToolLeft;private bool isSwingToolUp;private bool isSwingToolDown;private Camera mainCamera;private Rigidbody2D rigidbody2D;private Direction playerDirection;private float movementSpeed;private bool _playerInputIsDisabled = false;public bool PlayerInputIsDisabled { get => _playerInputIsDisabled; set => _playerInputIsDisabled = value; }protected override void Awake(){base.Awake();rigidbody2D = GetComponent<Rigidbody2D>();mainCamera = Camera.main;}private void Update(){#region  Player Inputif (!PlayerInputIsDisabled){ResetAnimationTrigger();PlayerMovementInput();PlayerWalkInput();// Send event to any listeners for player movement inputEventHandler.CallMovementEvent(xInput, yInput, isWalking, isRunning, isIdle, isCarrying, toolEffect,isUsingToolRight, isUsingToolLeft, isUsingToolUp, isUsingToolDown,isLiftingToolRight, isLiftingToolLeft, isLiftingToolUp, isLiftingToolDown,isPickingRight, isPickingLeft, isPickingUp, isPickingDown,isSwingToolRight, isSwingToolLeft, isSwingToolUp, isSwingToolDown,false, false, false, false);}#endregion Player Input}private void FixedUpdate(){PlayerMovement();}private void PlayerMovement(){Vector2 move = new Vector2(xInput * movementSpeed * Time.deltaTime, yInput * movementSpeed * Time.deltaTime);rigidbody2D.MovePosition(rigidbody2D.position + move);}private void ResetAnimationTrigger(){toolEffect = ToolEffect.none;isUsingToolRight = false;isUsingToolLeft = false;isUsingToolUp = false;isUsingToolDown = false;isLiftingToolRight = false;isLiftingToolLeft = false;isLiftingToolUp = false;isLiftingToolDown = false;isPickingRight = false;isPickingLeft = false;isPickingUp = false;isPickingDown = false;isSwingToolRight = false;isSwingToolLeft = false;isSwingToolUp = false;isSwingToolDown = false;}private void PlayerMovementInput(){xInput = Input.GetAxisRaw("Horizontal");yInput = Input.GetAxisRaw("Vertical");// 斜着移动if (xInput != 0 && yInput != 0) {xInput = xInput * 0.71f;yInput = yInput * 0.71f;}// 在移动if (xInput != 0 || yInput != 0) {isRunning = true;isWalking = false;isIdle = false;movementSpeed = Settings.runningSpeed;// Capture player direction for save gameif (xInput < 0){playerDirection = Direction.left;}else if (xInput > 0){playerDirection = Direction.right;}else if (yInput < 0){playerDirection = Direction.down;}else{playerDirection = Direction.up;}}else if(xInput == 0 && yInput == 0){isRunning = false;isWalking = false;isIdle = true;}}// 按住Shift键移动为walkprivate void PlayerWalkInput(){if(Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift)){isRunning = false;isWalking = true;isIdle = false;movementSpeed = Settings.walkingSpeed;}else{isRunning = true;isWalking = false;isIdle = false;movementSpeed = Settings.runningSpeed;}}public Vector3 GetPlayerViewportPosition(){// Vector3 viewport position for player (0,0) viewport bottom left, (1,1) viewport top rightreturn mainCamera.WorldToViewportPoint(gameObject.transform.position);}public void DisablePlayerInputAndResetMovement(){DisablePlayerInpupt();ResetMovement();// Send event to any listeners for player movement inputEventHandler.CallMovementEvent(xInput, yInput, isWalking, isRunning, isIdle, isCarrying, toolEffect,isUsingToolRight, isUsingToolLeft, isUsingToolUp, isUsingToolDown,isLiftingToolRight, isLiftingToolLeft, isLiftingToolUp, isLiftingToolDown,isPickingRight, isPickingLeft, isPickingUp, isPickingDown,isSwingToolRight, isSwingToolLeft, isSwingToolUp, isSwingToolDown,false, false, false, false);}private void ResetMovement(){// Reset movementxInput = 0f;yInput = 0f;isRunning = false;isWalking = false;isIdle = true;}public void DisablePlayerInpupt(){PlayerInputIsDisabled = true;}public void EnablePlayerInput(){PlayerInputIsDisabled = false;}
}

（3）修改UIInventoryBar.cs

创建对可拖动物体的引用。

public GameObject inventoryBarDraggedItem;

当我们从UIInventorySlot中取出道具时会填充该字段。

此时UIInventoryBar.cs的完整代码为：

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class UIInventoryBar : MonoBehaviour
{[SerializeField] private Sprite blank16x16sprite = null; // 插槽默认图案[SerializeField] private UIInventorySlot[] inventorySlot = null; // 所有插槽集合public GameObject inventoryBarDraggedItem;private RectTransform rectTransform;private bool _isInventoryBarPositionBottom = true;public bool IsInventoryBarPositionBottom { get { return _isInventoryBarPositionBottom;} set { _isInventoryBarPositionBottom = value; } }private void Awake(){rectTransform = GetComponent<RectTransform>();}private void OnDisable(){EventHandler.InventoryUpdatedEvent -= InventoryUpdated;}private void InventoryUpdated(InventoryLocation inventoryLocation, List<InventoryItem> inventoryList){if (inventoryLocation == InventoryLocation.player){ClearInventorySlots();if (inventorySlot.Length > 0 && inventoryList.Count > 0){for (int i = 0; i < inventorySlot.Length; i++){if (i < inventoryList.Count){int itemCode = inventoryList[i].itemCode;ItemDetails itemDetails = InventoryManager.Instance.GetItemDetails(itemCode);if (itemDetails != null){// add images and details to inventory item slotinventorySlot[i].inventorySlotImage.sprite = itemDetails.itemSprite;inventorySlot[i].textMeshProUGUI.text = inventoryList[i].itemQuantity.ToString();inventorySlot[i].itemDetails = itemDetails;inventorySlot[i].itemQuantity = inventoryList[i].itemQuantity;}}else{break;}}}}}private void ClearInventorySlots(){if(inventorySlot.Length > 0){// loop through inventory slots and update with blank spritefor(int i = 0; i < inventorySlot.Length; i++){inventorySlot[i].inventorySlotImage.sprite = blank16x16sprite;inventorySlot[i].textMeshProUGUI.text = "";inventorySlot[i].itemDetails = null;inventorySlot[i].itemQuantity = 0;}}}private void OnEnable(){EventHandler.InventoryUpdatedEvent += InventoryUpdated;}private void Update(){// Switch inventory bar position depending on player positionSwitchInventoryBarPosition();}private void SwitchInventoryBarPosition(){Vector3 playerViewportPosition = Player.Instance.GetPlayerViewportPosition();if (playerViewportPosition.y > 0.3f && IsInventoryBarPositionBottom == false){rectTransform.pivot = new Vector2(0.5f, 0f);rectTransform.anchorMin = new Vector2(0.5f, 0f);rectTransform.anchorMax = new Vector2(0.5f, 0f);rectTransform.anchoredPosition = new Vector2(0f, 2.5f);IsInventoryBarPositionBottom = true;}else if (playerViewportPosition.y <= 0.3f && IsInventoryBarPositionBottom == true) {rectTransform.pivot = new Vector2(0.5f, 1f);rectTransform.anchorMin = new Vector2(0.5f, 1f);rectTransform.anchorMax = new Vector2(0.5f, 1f);rectTransform.anchoredPosition = new Vector2(0f, -2.5f);IsInventoryBarPositionBottom = false;}}
}

（4）创建Dragged Item预制体

在Hierarchy -> PersistentScene -> UI -> MainGameUICanvas -> UICanvasGroup -> UIInventoryBar下创建InventoryDraggedItem空物体。设置其属性如下：

设置Sort Order=2是为了：当在UIInventoryBar上拖动时，能够更高优先级展示，从而不被Slot上的物体覆盖。

在InventoryDraggedItem下再创建Item空对象，其属性设置如下：

然后将InventoryDraggedItem拖到Assets -> Prefabs -> UI下

然后再删除Hierarchy中的InventoryDraggedItem对象。

点击InventoryDraggedItem预制体，设置其Render Mode为Screen Space - Overlay，勾选Pixel Perfect。

（5）设置inventoryBarDraggedItem属性

点击Hierarchy中的UIInventoryBar对象，将InventoryDraggedItem预制体拖入inventoryBarDraggedItem属性。

4、优化UIInventorySlot脚本

using UnityEngine;
using TMPro;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using System;public class UIInventorySlot : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{private Camera mainCamera;private Transform parentItem; // 场景中的物体父类private GameObject draggedItem; // 被拖动的物体public Image inventorySlotHighlight;public Image inventorySlotImage;public TextMeshProUGUI textMeshProUGUI;[SerializeField] private UIInventoryBar inventoryBar = null;[SerializeField] private GameObject itemPrefab = null;[HideInInspector] public ItemDetails itemDetails;[HideInInspector] public int itemQuantity;private void Start(){mainCamera = Camera.main;parentItem = GameObject.FindGameObjectWithTag(Tags.ItemsParentTransform).transform;}public void OnBeginDrag(PointerEventData eventData){if(itemDetails != null) {// Disable keyboard inputPlayer.Instance.DisablePlayerInputAndResetMovement();// Instatiate gameobject as dragged itemdraggedItem = Instantiate(inventoryBar.inventoryBarDraggedItem, inventoryBar.transform);// Get image for dragged itemImage draggedItemImage = draggedItem.GetComponentInChildren<Image>();draggedItemImage.sprite = inventorySlotImage.sprite;}}public void OnDrag(PointerEventData eventData){// move game object as dragged itemif(!draggedItem != null){draggedItem.transform.position = Input.mousePosition;}}public void OnEndDrag(PointerEventData eventData){// Destroy game object as dragged itemif (draggedItem != null) {Destroy(draggedItem);// if drag ends over inventory bar, get item drag is over and swap thenif (eventData.pointerCurrentRaycast.gameObject != null && eventData.pointerCurrentRaycast.gameObject.GetComponent<UIInventorySlot>() != null) {}else{// else attemp to drop the item if it can be droppedif (itemDetails.canBeDropped){DropSelectedItemAtMousePosition();}}// Enable player inputPlayer.Instance.EnablePlayerInput();}}/// <summary>/// Drops the item(if selected) at the current mouse position. called by the DropItem event/// </summary>private void DropSelectedItemAtMousePosition(){if(itemDetails != null){Vector3 worldPosition = mainCamera.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, -mainCamera.transform.position.z));// Create item from prefab at mouse positionGameObject itemGameObject = Instantiate(itemPrefab, worldPosition, Quaternion.identity, parentItem);Item item = itemGameObject.GetComponent<Item>();item.ItemCode = itemDetails.itemCode;// Remove item from player's inventoryInventoryManager.Instance.RemoveItem(InventoryLocation.player, item.ItemCode);}}
}

1）针对draggedItemImage.sprite = inventorySlotImage.sprite;的代码：

当点击/拖动某个具体Slot时，就会执行该Slot对应的UIInventorySlot脚本，也可以获取到对应的Slot Image信息。

2）针对item.ItemCode = itemDetails.itemCode;

itemDetails属性为UIInventorySlot的public属性。

当添加一个物体时，会触发CallInventoryUpdatedEvent事件，从而更新每个Slot的itemDetails值。

5、优化InventoryManager脚本

增加RemoveItem和RemoveItemAtPosition两个函数。

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class InventoryManager : SingletonMonobehaviour<InventoryManager>
{private Dictionary<int, ItemDetails> itemDetailsDictionary;public List<InventoryItem>[] inventoryLists; // 每个位置的库存清单// 每个位置的库存数。 The index of the array is the inventory list(from the// InventoryLocation enum), and the value is the capacity of that inventory list[HideInInspector] public int[] inventoryListCapacityIntArray; [SerializeField] private SO_ItemList itemList = null;protected override void Awake(){base.Awake();// Create Inventory listsCreateInventoryLists();// Create item details dictionaryCreateItemDetailsDictionary();}private void CreateInventoryLists(){inventoryLists = new List<InventoryItem>[(int)InventoryLocation.count];for (int i = 0; i < (int)InventoryLocation.count; i++){inventoryLists[i] = new List<InventoryItem>();}// initialize inventory list capacity arrayinventoryListCapacityIntArray = new int[(int)InventoryLocation.count];// initialize player inventory list capacityinventoryListCapacityIntArray[(int)InventoryLocation.player] = Settings.playerInitialInventoryCapacity;}/// <summary>/// Populates the itemDetailsDictionary from the scriptable object items list/// </summary>private void CreateItemDetailsDictionary(){itemDetailsDictionary = new Dictionary<int, ItemDetails>();foreach (ItemDetails itemDetails in itemList.itemDetails) {itemDetailsDictionary.Add(itemDetails.itemCode, itemDetails);}}/// <summary>/// Add an item to the inventory list for the inventoryLocation and then destroy the gameObjectToDelete/// 角色拾取到物品后，物品需要消失掉/// </summary>/// <param name="inventoryLocation"></param>/// <param name="item"></param>/// <param name="gameObjectToDelete"></param>public void AddItem(InventoryLocation inventoryLocation, Item item, GameObject gameObjectToDelete){AddItem(inventoryLocation, item);Destroy(gameObjectToDelete);}/// <summary>/// Add an item to the inventory list for the inventoryLocation/// </summary>/// <param name="inventoryLocation"></param>/// <param name="item"></param>public void AddItem(InventoryLocation inventoryLocation, Item item){int itemCode = item.ItemCode;List<InventoryItem> inventoryList = inventoryLists[(int)inventoryLocation];// Check if inventory already contains the itemint itemPosition = FindItemInInventory(inventoryLocation, itemCode);if(itemPosition != -1){AddItemPosition(inventoryList, itemCode, itemPosition);}else{AddItemPosition(inventoryList, itemCode);}// Send event that inventory has been updatedEventHandler.CallInventoryUpdatedEvent(inventoryLocation, inventoryLists[(int)inventoryLocation]);  }/// <summary>/// Add item to position in the inventory/// </summary>/// <param name="inventoryList"></param>/// <param name="itemCode"></param>/// <param name="position"></param>/// <exception cref="NotImplementedException"></exception>private void AddItemPosition(List<InventoryItem> inventoryList, int itemCode, int position){InventoryItem inventoryItem = new InventoryItem();int quantity = inventoryList[position].itemQuantity + 1;inventoryItem.itemQuantity = quantity;inventoryItem.itemCode = itemCode;inventoryList[position] = inventoryItem;Debug.ClearDeveloperConsole();//DebugPrintInventoryList(inventoryList);}/// <summary>/// Remove an item from the inventory, and create a game object at the position it was dropped/// </summary>/// <param name="inventoryLocation"></param>/// <param name="itemCode"></param>public void RemoveItem(InventoryLocation inventoryLocation, int itemCode){List<InventoryItem> inventoryList = inventoryLists[(int)inventoryLocation];// Check if inventory already contains the itemint itemPosition = FindItemInInventory(inventoryLocation, itemCode);if(itemPosition != -1){RemoveItemAtPosition(inventoryList, itemCode, itemPosition);}// Send event that inventory has been updatedEventHandler.CallInventoryUpdatedEvent(inventoryLocation, inventoryLists[(int)inventoryLocation]);}private void RemoveItemAtPosition(List<InventoryItem> inventoryList, int itemCode, int position){InventoryItem inventoryItem = new InventoryItem();int quantity = inventoryList[position].itemQuantity - 1;if(quantity > 0){inventoryItem.itemQuantity = quantity;inventoryItem.itemCode = itemCode;inventoryList[position] = inventoryItem;}else{inventoryList.RemoveAt(position);   }}private void DebugPrintInventoryList(List<InventoryItem> inventoryList){foreach(InventoryItem inventoryItem in inventoryList){Debug.Log("Item Description:" + InventoryManager.Instance.GetItemDetails(inventoryItem.itemCode).itemDescription + "    Item Quantity:" + inventoryItem.itemQuantity);}Debug.Log("*******************************************************************************");}/// <summary>/// Add item to the end of the inventory /// </summary>/// <param name="inventoryList"></param>/// <param name="itemCode"></param>/// <exception cref="NotImplementedException"></exception>private void AddItemPosition(List<InventoryItem> inventoryList, int itemCode){InventoryItem inventoryItem = new InventoryItem(); inventoryItem.itemCode = itemCode;inventoryItem.itemQuantity = 1;inventoryList.Add(inventoryItem);//DebugPrintInventoryList(inventoryList);}/// <summary>/// Find if an itemCode is already in the inventory. Returns the item position/// in the inventory list, or -1 if the item is not in the inventory/// </summary>/// <param name="inventoryLocation"></param>/// <param name="itemCode"></param>/// <returns></returns>/// <exception cref="NotImplementedException"></exception>private int FindItemInInventory(InventoryLocation inventoryLocation, int itemCode){List<InventoryItem> inventoryList = inventoryLists[(int)inventoryLocation];for (int i = 0; i < inventoryList.Count; i++){if(inventoryList[i].itemCode == itemCode){return i;}}return -1;}/// <summary>/// Returns the itemDetails (from the SO_ItemList) for the itemCode, or null if the item doesn't exist/// </summary>/// <param name="itemCode"></param>/// <returns></returns>public ItemDetails GetItemDetails(int itemCode) {ItemDetails itemDetails;if(itemDetailsDictionary.TryGetValue(itemCode, out itemDetails)){return itemDetails;}else{return null;}}
}

6、填充InventorySlot面板属性

这两个属性没法从prefab中直接选择对象进行设置，所以需要在InventorySlot实例化之后的对象们中一一进行设置。

先同时选中UIInventorySlot0~11，然后设置属性如下：

此时运行程序，即可实现从库存栏中拖拽物品到游戏场景中。

7、交换库存栏中商品的位置

（1）修改UIInventorySlot脚本

首先，添加slotNumber用于标记插槽的序列号。

[SerializeField] private int slotNumber = 0; // 插槽的序列号

然后当点击结束处为slot对象时，交换两个slot的位置。

此时UIInventorySlot的完整代码如下：

using UnityEngine;
using TMPro;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using System;public class UIInventorySlot : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{private Camera mainCamera;private Transform parentItem; // 场景中的物体父类private GameObject draggedItem; // 被拖动的物体public Image inventorySlotHighlight;public Image inventorySlotImage;public TextMeshProUGUI textMeshProUGUI;[SerializeField] private UIInventoryBar inventoryBar = null;[SerializeField] private GameObject itemPrefab = null;[SerializeField] private int slotNumber = 0; // 插槽的序列号[HideInInspector] public ItemDetails itemDetails;[HideInInspector] public int itemQuantity;private void Start(){mainCamera = Camera.main;parentItem = GameObject.FindGameObjectWithTag(Tags.ItemsParentTransform).transform;}public void OnBeginDrag(PointerEventData eventData){if(itemDetails != null) {// Disable keyboard inputPlayer.Instance.DisablePlayerInputAndResetMovement();// Instatiate gameobject as dragged itemdraggedItem = Instantiate(inventoryBar.inventoryBarDraggedItem, inventoryBar.transform);// Get image for dragged itemImage draggedItemImage = draggedItem.GetComponentInChildren<Image>();draggedItemImage.sprite = inventorySlotImage.sprite;}}public void OnDrag(PointerEventData eventData){// move game object as dragged itemif(!draggedItem != null){draggedItem.transform.position = Input.mousePosition;}}public void OnEndDrag(PointerEventData eventData){// Destroy game object as dragged itemif (draggedItem != null) {Destroy(draggedItem);// if drag ends over inventory bar, get item drag is over and swap thenif (eventData.pointerCurrentRaycast.gameObject != null && eventData.pointerCurrentRaycast.gameObject.GetComponent<UIInventorySlot>() != null) {// get the slot number where the drag endedint toSlotNumber = eventData.pointerCurrentRaycast.gameObject.GetComponent<UIInventorySlot>().slotNumber;// Swap inventory items in inventory listInventoryManager.Instance.SwapInventoryItems(InventoryLocation.player, slotNumber, toSlotNumber);}else{// else attemp to drop the item if it can be droppedif (itemDetails.canBeDropped){DropSelectedItemAtMousePosition();}}// Enable player inputPlayer.Instance.EnablePlayerInput();}}/// <summary>/// Drops the item(if selected) at the current mouse position. called by the DropItem event/// </summary>private void DropSelectedItemAtMousePosition(){if(itemDetails != null){Vector3 worldPosition = mainCamera.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, -mainCamera.transform.position.z));// Create item from prefab at mouse positionGameObject itemGameObject = Instantiate(itemPrefab, worldPosition, Quaternion.identity, parentItem);Item item = itemGameObject.GetComponent<Item>();item.ItemCode = itemDetails.itemCode;// Remove item from player's inventoryInventoryManager.Instance.RemoveItem(InventoryLocation.player, item.ItemCode);}}
}

（2）修改InventoryManager脚本

新增如下代码：

public void SwapInventoryItems(InventoryLocation inventoryLocation, int fromItem, int toItem)
{// if fromItem index and toItemIndex are within the bounds of the list, not the same, and greater than or equal to zeroif(fromItem < inventoryLists[(int)inventoryLocation].Count && toItem < inventoryLists[(int)inventoryLocation].Count&& fromItem != toItem && fromItem >= 0 && toItem >= 0){InventoryItem fromInventoryItem = inventoryLists[(int)inventoryLocation][fromItem];InventoryItem toInventoryItem = inventoryLists[(int)inventoryLocation][toItem];inventoryLists[(int)inventoryLocation][toItem] = fromInventoryItem;inventoryLists[(int)inventoryLocation][fromItem] = toInventoryItem;// Send event that inventory has been updatedEventHandler.CallInventoryUpdatedEvent(inventoryLocation, inventoryLists[(int)inventoryLocation]);}
}

此时InventoryManager.cs完整代码如下：

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class InventoryManager : SingletonMonobehaviour<InventoryManager>
{private Dictionary<int, ItemDetails> itemDetailsDictionary;public List<InventoryItem>[] inventoryLists; // 每个位置的库存清单// 每个位置的库存数。 The index of the array is the inventory list(from the// InventoryLocation enum), and the value is the capacity of that inventory list[HideInInspector] public int[] inventoryListCapacityIntArray; [SerializeField] private SO_ItemList itemList = null;protected override void Awake(){base.Awake();// Create Inventory listsCreateInventoryLists();// Create item details dictionaryCreateItemDetailsDictionary();}private void CreateInventoryLists(){inventoryLists = new List<InventoryItem>[(int)InventoryLocation.count];for (int i = 0; i < (int)InventoryLocation.count; i++){inventoryLists[i] = new List<InventoryItem>();}// initialize inventory list capacity arrayinventoryListCapacityIntArray = new int[(int)InventoryLocation.count];// initialize player inventory list capacityinventoryListCapacityIntArray[(int)InventoryLocation.player] = Settings.playerInitialInventoryCapacity;}/// <summary>/// Populates the itemDetailsDictionary from the scriptable object items list/// </summary>private void CreateItemDetailsDictionary(){itemDetailsDictionary = new Dictionary<int, ItemDetails>();foreach (ItemDetails itemDetails in itemList.itemDetails) {itemDetailsDictionary.Add(itemDetails.itemCode, itemDetails);}}/// <summary>/// Add an item to the inventory list for the inventoryLocation and then destroy the gameObjectToDelete/// 角色拾取到物品后，物品需要消失掉/// </summary>/// <param name="inventoryLocation"></param>/// <param name="item"></param>/// <param name="gameObjectToDelete"></param>public void AddItem(InventoryLocation inventoryLocation, Item item, GameObject gameObjectToDelete){AddItem(inventoryLocation, item);Destroy(gameObjectToDelete);}/// <summary>/// Add an item to the inventory list for the inventoryLocation/// </summary>/// <param name="inventoryLocation"></param>/// <param name="item"></param>public void AddItem(InventoryLocation inventoryLocation, Item item){int itemCode = item.ItemCode;List<InventoryItem> inventoryList = inventoryLists[(int)inventoryLocation];// Check if inventory already contains the itemint itemPosition = FindItemInInventory(inventoryLocation, itemCode);if(itemPosition != -1){AddItemPosition(inventoryList, itemCode, itemPosition);}else{AddItemPosition(inventoryList, itemCode);}// Send event that inventory has been updatedEventHandler.CallInventoryUpdatedEvent(inventoryLocation, inventoryLists[(int)inventoryLocation]);  }/// <summary>/// Add item to position in the inventory/// </summary>/// <param name="inventoryList"></param>/// <param name="itemCode"></param>/// <param name="position"></param>/// <exception cref="NotImplementedException"></exception>private void AddItemPosition(List<InventoryItem> inventoryList, int itemCode, int position){InventoryItem inventoryItem = new InventoryItem();int quantity = inventoryList[position].itemQuantity + 1;inventoryItem.itemQuantity = quantity;inventoryItem.itemCode = itemCode;inventoryList[position] = inventoryItem;Debug.ClearDeveloperConsole();//DebugPrintInventoryList(inventoryList);}/// <summary>/// Remove an item from the inventory, and create a game object at the position it was dropped/// </summary>/// <param name="inventoryLocation"></param>/// <param name="itemCode"></param>public void RemoveItem(InventoryLocation inventoryLocation, int itemCode){List<InventoryItem> inventoryList = inventoryLists[(int)inventoryLocation];// Check if inventory already contains the itemint itemPosition = FindItemInInventory(inventoryLocation, itemCode);if(itemPosition != -1){RemoveItemAtPosition(inventoryList, itemCode, itemPosition);}// Send event that inventory has been updatedEventHandler.CallInventoryUpdatedEvent(inventoryLocation, inventoryLists[(int)inventoryLocation]);}private void RemoveItemAtPosition(List<InventoryItem> inventoryList, int itemCode, int position){InventoryItem inventoryItem = new InventoryItem();int quantity = inventoryList[position].itemQuantity - 1;if(quantity > 0){inventoryItem.itemQuantity = quantity;inventoryItem.itemCode = itemCode;inventoryList[position] = inventoryItem;}else{inventoryList.RemoveAt(position);   }}/// <summary>/// Swap item at fromItem index with item at toItem index in inventoryLocation inventory list/// </summary>/// <param name="inventoryLocation"></param>/// <param name="fromItem"></param>/// <param name="toItem"></param>public void SwapInventoryItems(InventoryLocation inventoryLocation, int fromItem, int toItem){// if fromItem index and toItemIndex are within the bounds of the list, not the same, and greater than or equal to zeroif(fromItem < inventoryLists[(int)inventoryLocation].Count && toItem < inventoryLists[(int)inventoryLocation].Count&& fromItem != toItem && fromItem >= 0 && toItem >= 0){InventoryItem fromInventoryItem = inventoryLists[(int)inventoryLocation][fromItem];InventoryItem toInventoryItem = inventoryLists[(int)inventoryLocation][toItem];inventoryLists[(int)inventoryLocation][toItem] = fromInventoryItem;inventoryLists[(int)inventoryLocation][fromItem] = toInventoryItem;// Send event that inventory has been updatedEventHandler.CallInventoryUpdatedEvent(inventoryLocation, inventoryLists[(int)inventoryLocation]);}}private void DebugPrintInventoryList(List<InventoryItem> inventoryList){foreach(InventoryItem inventoryItem in inventoryList){Debug.Log("Item Description:" + InventoryManager.Instance.GetItemDetails(inventoryItem.itemCode).itemDescription + "    Item Quantity:" + inventoryItem.itemQuantity);}Debug.Log("*******************************************************************************");}/// <summary>/// Add item to the end of the inventory /// </summary>/// <param name="inventoryList"></param>/// <param name="itemCode"></param>/// <exception cref="NotImplementedException"></exception>private void AddItemPosition(List<InventoryItem> inventoryList, int itemCode){InventoryItem inventoryItem = new InventoryItem(); inventoryItem.itemCode = itemCode;inventoryItem.itemQuantity = 1;inventoryList.Add(inventoryItem);//DebugPrintInventoryList(inventoryList);}/// <summary>/// Find if an itemCode is already in the inventory. Returns the item position/// in the inventory list, or -1 if the item is not in the inventory/// </summary>/// <param name="inventoryLocation"></param>/// <param name="itemCode"></param>/// <returns></returns>/// <exception cref="NotImplementedException"></exception>private int FindItemInInventory(InventoryLocation inventoryLocation, int itemCode){List<InventoryItem> inventoryList = inventoryLists[(int)inventoryLocation];for (int i = 0; i < inventoryList.Count; i++){if(inventoryList[i].itemCode == itemCode){return i;}}return -1;}/// <summary>/// Returns the itemDetails (from the SO_ItemList) for the itemCode, or null if the item doesn't exist/// </summary>/// <param name="itemCode"></param>/// <returns></returns>public ItemDetails GetItemDetails(int itemCode) {ItemDetails itemDetails;if(itemDetailsDictionary.TryGetValue(itemCode, out itemDetails)){return itemDetails;}else{return null;}}
}

（3）更新Inspector中的slotNumber值

依次修改UIInventorySlot0~11中的SlotNumber值。