无法动态设置图像 object 的图像

Question

I'm trying to make an inventory system. When the player presses tab, a UI opens with three images. I dragged all three images from the Hierarchy into an Image array, and I want to iterate through this array and set the image of each image object to an image path that I have in a string array.

The images are not updating at all, and I don't know why. The errors being spammed are strange and are thrown even when I comment out the call to updateimages(), so I'm not sure if they are relevent.

the error being spammed:

Edit: relaunching Unity got rid of the error being spammed. Images are still not being updated.

// update images dynamically.
//array is a string array filled with image paths.
//objects is an array of images from the Hierarchy.

private void updateimages()
{
    for (int i = 0; i < 3; i++)
    {
        objects[i].GetComponent<Image>().sprite = Resources.Load<Sprite>(array[i]);
        // not working, images are still blank.
    }
    
    /* Does not work either.
    for (int i = 0; i < 3; i++)
    {
        Texture2D spriteTexture = LoadTexture(array[i]);
        if (spriteTexture != null)
        {
            Sprite sprite = Sprite.Create(spriteTexture, new Rect(0, 0, spriteTexture.width, spriteTexture.height), Vector2.zero);
            objects[i].sprite = sprite;
        }
    }
    */
}

private Dictionary<int, int> itemInventory;     // Item ID to quantity mapping
private Dictionary<int, string> itemNameLookup; // Item ID to name mapping
private Dictionary<string, string> itemToImage; // Item Name to image path mapping

itemToImage = new Dictionary<string, string>();
itemToImage.Add("Health Pack", Application.dataPath + "/Player_Types/Item_Health.png");
itemToImage.Add("Poop", Application.dataPath + "/Player_Types/Item_Poop.png");



this block fills the array with image paths. 
// iterate through inventory
foreach (KeyValuePair<int, int> entry in itemInventory) 
{
    // iterate through item names
    foreach (KeyValuePair<int, string> entry_i in itemNameLookup)  
        {
            // if inventoryitem.key == itemname.key
            if (entry.Key == entry_i.Key)  
            {
                //get image path from itemName.value into an array.
                array.Append(itemToImage[entry_i.Value]);
            }
        }
}

Answer 1

The path used in the resources api is relative to the Resources folder(s) in your project. Remove the Application.dataPath portion of the paths and make sure the paths are relative to the Resources folder(s).

From Docs

for example loading a GameObject at "Assets/Guns/Resources/Shotgun.prefab" would only require "Shotgun" as the path.

The Resources are compiled into your project.
You cannot add to the resources of a compiled build.

Answer 2

My problem was trying to load textures into a sprite. I thought a sprite was just an image, so setting the sprite to a.png file I set to a texture in the engine made sense to me. I fixed it by creating a sprite with the texture, then setting the image object's sprite to the sprite I created.

Problem line:

objects[i].GetComponent<Image>().sprite = Resources.Load<Sprite>(array[i]);

soulution:

Sprite tmp = Sprite.Create(ACTIVE_INVENTORY[i].texture, new Rect(0.0f, 0.0f, ACTIVE_INVENTORY[i].texture.width, ACTIVE_INVENTORY[i].texture.height), new Vector2(0.5f, 0.5f), 100.0f);
objects[i].sprite = tmp; // set the inventory slot's image to the image of the item
objectNames[i].text = ACTIVE_INVENTORY[i].itemName; // set item name to item.