Unity backpack system

Tips ： The following is the main body of this article

Briefly explain

utilize ScriptableObject Custom resource script saves data

Backpack system material

1. scene
   
2. GUI

3. Gear

UI Simply create

1、 establish Panel

2、Panel nesting Img、button

effect ：

3、Panel Nested management grid Img、 Lick and add Grid Layout Group Components , Use components to adjust the grid layout

4、 Nested mesh Img Nest again Img Nest again Text

The effect is shown below ：

The same four nested grids Img Nest again Button Nest again Text

Realize data storage

5. establish Item Save data script

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

[CreateAssetMenu(fileName = "Item", menuName = "Item")]
public class Item : ScriptableObject
{
    [Header(" Equipment pictures ")]
    public Sprite ItemSprite;
    [Header(" Equipment name ")]
    public string ItemName;
    [Header(" Equipment quantity ")]
    public int ItemCount;

    [Header(" Equipment details ")]
    [TextArea]
    public string ItemInfo;

    [Header(" equipment ")]
    public bool Equip;
    
}

7、. Create a data manager

8、 Use List Create a backpack system for storing data

using System.Collections.Generic;
using UnityEngine;

[CreateAssetMenu(fileName = "InventoryScript", menuName = "InventoryScript")]
public class Inventory : ScriptableObject
{
    // Create a backpack system ： list 
    public List<Item> ItemList = new List<Item>();
}

9、. establish WorldEquip( Preparation in the world )： Script

using UnityEngine;

public class WorldEquip : MonoBehaviour
{
    public Item item;
    public Inventory inventory;

    private void OnTriggerEnter2D(Collider2D collision)
    {
        if (collision.CompareTag("Player"))
        {
            if (!inventory.ItemList.Contains(item))
            {
                inventory.ItemList.Add(item);
            }
            else
            {
                item.ItemCount++;
            }
             Pick up items and generate corresponding items 
            InvensoryManager.UpdateEquipState(); 
        }
    }
}

technological process ：WorldEquip Ground equipment meets detection and licks to ItemList（ Backpack system ）

The effect is as follows ：

Realize data display

10、. Grid own script 、 Create a generated mesh Grid Script 、 Display equipment 、 Lick equipment details, etc

 Grid own script 
using UnityEngine;
using UnityEngine.UI;

public class Slot : MonoBehaviour
{
	 Click on the equipment to display the corresponding details 
    public Item slotItem;
    
     picture 
    public Image slotImg;
    
     Quantity of equipment 
    public Text slotText;
    
	 Click to display the corresponding details 
    public void ItemOnClick()
    {
        InvensoryManager.UpdateInformation(slotItem.ItemInfo);
    }
}

 Create a generated mesh Grid Script 
using UnityEngine;
using UnityEngine.UI;

public class InvensoryManager : MonoBehaviour
{
    public static InvensoryManager Instance;
	
	 knapsack 
    public Inventory myBag;
	 Father of grid 
    public GameObject slotGrid;
     Grid of equipment 
    public Slot slotPrefeb;
     Details text 
    public Text itemInfromation;

    private void Awake()
    {
        if (Instance != null)
            Destroy(gameObject);
        Instance = this;
    }
	
	 start-up play Update backpack equipment 
    private void OnEnable()
    {
        UpdateEquipState();
    }
    
     Lick add equipment details function 
    public static void UpdateInformation(string informText)
    {
        Instance.itemInfromation.text = informText;
    }
	
	 Update backpack equipment 
    public static void UpdateBag(Item item)
    {
        Slot newItem = Instantiate(Instance.slotPrefeb,Instance.slotGrid.transform.position, Quaternion.identity);
        newItem.gameObject.transform.SetParent(Instance.slotGrid.transform);
        newItem.slotItem = item;
        newItem.slotImg.sprite = item.ItemSprite;
        newItem.slotText.text = item.ItemCount.ToString();
    }

    public static void UpdateEquipState()
    {
        for (int i = 0; i < Instance.slotGrid.transform.childCount; i++)
        {
            if (Instance.slotGrid.transform.childCount ==0)
                break;
            Destroy(Instance.slotGrid.transform.GetChild(i).gameObject);
        }
        for (int i = 0; i < Instance.myBag.ItemList.Count; i++)
        {
            UpdateBag(Instance.myBag.ItemList[i]);
        }
    }
}

technological process ： Create grid self generating script Slot, picture 、 written words 、 Click and so on to execute through the trigger condition of the equipment InvensoryManager Manage script functions and then give Slot Assignment etc.
effect ： as follows

Realize the dragging of equipment

11、 Realize the dragging and exchanging of backpacks

Because you need to lick and exchange positions and other functions, you need to make adjustments ：
technological process ： First give the backpack system Inventory Set the seat and then judge the position Item Is it empty , Hide when empty , If not, it will be displayed and assigned

UI adjustment

 Code tuning 

 Create a generated mesh Grid Script 
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class InvensoryManager : MonoBehaviour
{
    public static InvensoryManager Instance;

    public Inventory myBag;

    public GameObject slotGrid;

    //public Slot slotPrefeb;

    public GameObject slotObj;

    public Text itemInfromation;

    private List<GameObject> slotObjList = new List<GameObject>();

    private void Awake()
    {
        if (Instance != null)
            Destroy(gameObject);
        Instance = this;
    }

    private void OnEnable()
    {
        itemInfromation.text = "";
        UpdateEquipState();
    }
    //private void OnDisable()
    //{
    //    myBag.ItemList.Clear();
    //}

    public static void UpdateInformation(string informText)
    {
        Instance.itemInfromation.text = informText;
    }

    //public static void UpdateBag(Item item)
    //{
    //    Slot newItem = Instantiate(Instance.slotPrefeb,Instance.slotGrid.transform.position, Quaternion.identity);
    //    newItem.gameObject.transform.SetParent(Instance.slotGrid.transform);
    //    newItem.slotItem = item;
    //    newItem.slotImg.sprite = item.ItemSprite;
    //    newItem.slotText.text = item.ItemCount.ToString();
    //}

    public static void UpdateEquipState()
    {
        for (int i = 0; i < Instance.slotGrid.transform.childCount; i++)
        {
            if (Instance.slotGrid.transform.childCount ==0)
                break;
            Destroy(Instance.slotGrid.transform.GetChild(i).gameObject);
            Instance.slotObjList.Clear();
        }
        for (int i = 0; i < Instance.myBag.ItemList.Count; i++)
        {
            //updatebag(instance.mybag.itemlist[i]);
            Instance.slotObjList.Add(Instantiate(Instance.slotObj));
            Instance.slotObjList[i].transform.SetParent(Instance.slotGrid.transform);
            Instance.slotObjList[i].GetComponent<Slot>().SetUpSlot(Instance.myBag.ItemList[i]);
        }
    }


 Grid own script 
using UnityEngine;
using UnityEngine.UI;

public class Slot : MonoBehaviour
{
    public Item slotItem;
    public Image slotImg;
    public Text slotText;
    private string slotInfo;

    public GameObject itemInSlot;

    public void ItemOnClick()
    {
        InvensoryManager.UpdateInformation(slotInfo);
    }
    
    public void SetUpSlot(Item item)
    {
        if (item == null)
        {
            itemInSlot.SetActive(false);
            return;
        }
        slotImg.sprite = item.ItemSprite;
        slotText.text = item.ItemCount.ToString();
        slotInfo = item.ItemInfo;
    }
}
}

 Use List Create a backpack system for storing data 
using UnityEngine;

public class WorldEquip : MonoBehaviour
{
    public Item item;
    public Inventory inventory;

    private void OnTriggerEnter2D(Collider2D collision)
    {
        Destroy(gameObject);

        if (collision.CompareTag("Player"))
        {
            if (!inventory.ItemList.Contains(item))
            {
                //inventory.ItemList.Add(item);
                for (int i = 0; i < inventory.ItemList.Count; i++)
                {
                    if (inventory.ItemList[i] == null)
                    {
                        inventory.ItemList[i] = item;
                        break;
                    }
                }
                item.ItemCount++;
            }
            else
            {
                item.ItemCount++;
            }
            InvensoryManager.UpdateEquipState();
        }
    }
}

 Dragging of backpack 
using UnityEngine;
using UnityEngine.EventSystems;

public class MouseBag : MonoBehaviour,IDragHandler
{
    private RectTransform rectTransform;
    public Canvas canvas;

    private void Awake()
    {
        rectTransform = GetComponent<RectTransform>();
    }

    public void OnDrag(PointerEventData eventData)
    {
    	UI In the center of + Where the mouse clicks （ Very easy to use ）
        rectTransform.anchoredPosition += eventData.delta;
    }
}

 Exchange of equipment 
using UnityEngine;
using UnityEngine.EventSystems;

public class ItemOnDrag : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{

    private Transform originalPos;
	
	 Mouse click 
    public void OnBeginDrag(PointerEventData eventData)
    {
        originalPos = transform.parent;
        transform.transform.SetParent(transform.parent.parent.parent);
        transform.position = eventData.position;   
    }

	 Mouse dragging 
    public void OnDrag(PointerEventData eventData)
    {
        transform.position = eventData.position;
        
        Canvas Group Components 
        GetComponent<CanvasGroup>().blocksRaycasts = false;
        
         Print the object at the ray 
        Debug.Log(eventData.pointerCurrentRaycast.gameObject);

    }

	 Release the mouse 
    public void OnEndDrag(PointerEventData eventData)
    {
        if (eventData.pointerCurrentRaycast.gameObject.name == "Image")
        {
            transform.SetParent(eventData.pointerCurrentRaycast.gameObject.transform.parent.parent);
            transform.position = eventData.pointerCurrentRaycast.gameObject.transform.parent.parent.position;
            eventData.pointerCurrentRaycast.gameObject.transform.parent.position = originalPos.position;
            eventData.pointerCurrentRaycast.gameObject.transform.parent.SetParent(originalPos);
            
	        Canvas Group Components 
            GetComponent<CanvasGroup>().blocksRaycasts = true;
            return;
        }
        transform.SetParent(eventData.pointerCurrentRaycast.gameObject.transform);
        transform.position = eventData.pointerCurrentRaycast.gameObject.transform.position;
        Canvas Group Components 
        GetComponent<CanvasGroup>().blocksRaycasts = true;
    }
}

technological process ： Use using UnityEngine.EventSystems Interface implementation under namespace UI Mobile knot and Canvas Group Component judgment

The effect is as follows ：

Adjustment issues

12、 Adjust small problems
The modified code is as follows

using UnityEngine;
using UnityEngine.EventSystems;

public class ItemOnDrag : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{

    private Transform originalPos;

    public Inventory MyBag;

    private int currentSoltID;
    
    public void OnBeginDrag(PointerEventData eventData)
    {
        originalPos = transform.parent;
        currentSoltID = originalPos.GetComponent<Slot>().slotID;
        transform.transform.SetParent(transform.parent.parent.parent);
        transform.position = eventData.position;
    }

    public void OnDrag(PointerEventData eventData)
    {
        transform.position = eventData.position;
        GetComponent<CanvasGroup>().blocksRaycasts = false;
    }

    public void OnEndDrag(PointerEventData eventData)
    {
        if(eventData.pointerCurrentRaycast.gameObject.name !=null)
            if (eventData.pointerCurrentRaycast.gameObject.name == "Image")
            {
                transform.SetParent(eventData.pointerCurrentRaycast.gameObject.transform.parent.parent);
                transform.position = eventData.pointerCurrentRaycast.gameObject.transform.parent.parent.position;

                //ItemList Database text exchange  
                var temp = MyBag.ItemList[currentSoltID];
                MyBag.ItemList[currentSoltID] = MyBag.ItemList[eventData.pointerCurrentRaycast.gameObject.transform.GetComponentInParent<Slot>().slotID];
                MyBag.ItemList[eventData.pointerCurrentRaycast.gameObject.transform.GetComponentInParent<Slot>().slotID] = temp;

                eventData.pointerCurrentRaycast.gameObject.transform.parent.position = originalPos.position;
                eventData.pointerCurrentRaycast.gameObject.transform.parent.SetParent(originalPos);
                GetComponent<CanvasGroup>().blocksRaycasts = true;

                return;
            }
            if(eventData.pointerCurrentRaycast.gameObject.name == "Grid(Clone)")
            {
                MyBag.ItemList[eventData.pointerCurrentRaycast.gameObject.GetComponentInParent<Slot>().slotID] = MyBag.ItemList[currentSoltID];
                if (eventData.pointerCurrentRaycast.gameObject.GetComponentInParent<Slot>().slotID!= currentSoltID)
                    MyBag.ItemList[currentSoltID] = null;

                transform.SetParent(eventData.pointerCurrentRaycast.gameObject.transform);
                transform.position = eventData.pointerCurrentRaycast.gameObject.transform.position;
                GetComponent<CanvasGroup>().blocksRaycasts = true;
                return;
            }
            // Other places   Equipment return 
            transform.SetParent(originalPos);
            transform.position = originalPos.position;
            GetComponent<CanvasGroup>().blocksRaycasts = true;
    }
}

effect ：

Complete data storage

13、 Complete data storage

* You can skip to the data storage and see the instructions PlayerPrefs&&JsonUtility

using UnityEngine;

public class SaverData : MonoBehaviour
{
	// Test use 
    private void Update()
    {
        if (Input.GetKeyDown(KeyCode.R))
        {
             SaveBagData();
        }
        if (Input.GetKeyDown(KeyCode.T))
        {
            LoadBagData();
        }
    }

    private void OnEnable()
    {
        LoadBagData();
    }

    private void OnDisable()
    {
        SaveBagData();
    }


    public void SaveBagData()
    {
        for (int i = 0; i < inventory.ItemList.Count; i++)
        {
            if (inventory.ItemList[i] != null)
            {
                Save(inventory.ItemList[i], inventory.ItemList[i].name);
                Debug.Log(inventory.ItemList[i].ItemCount);
            }
        }
    }

    public void LoadBagData()
    {
        for (int i = 0; i < inventory.ItemList.Count; i++)
        {
            if (inventory.ItemList[i] != null)
            {
                Load(inventory.ItemList[i], inventory.ItemList[i].name);
            }
        }
    }

    pri Please add a picture description 

}

effect ：