Unity3D: loading and using sprite atlas from Resources

Trabla: Unity3D: loading and using sprite atlas from Resources

Solving:


1. Create sprite atlas ( .png file images, background transparent )

"sprite-atlas.png" File

2. Create new unity2D project

3. Create folder "Resources" in folder "Assets"
and drag-n-drop sprite atlas file into folder "Resources"

4. Select sprite atlas file - set "Sprite Mode" -> "Multiple" + click "Apply"

5. Click "Sprite Editor" - slice sprite in automatic mode - will create separate sprites.

Slice Result

6. Create following UI structure:
Panel
- Text
- Button
- Image

7. Create new C# script , name it "SpriteAtlasController"  and add as component to "Panel"

8. Copy following code into "SpriteAtlasController.cs"

using UnityEngine;
using System.Collections;
using UnityEngine.UI; // Add this directive for UI Components e.g. Text, Button etc.
using System.Collections.Generic; 


public class SpriteAtlasController : MonoBehaviour {

public Button btnChangeImage;
public Text txtImageName;
public Image imgImage;

Sprite[] arrSprites;
int spriteIndexInArray = -1;

// Use this for initialization
void Start () {

Debug.Log("Try to load : sprite-atlas ");
arrSprites = Resources.LoadAll<Sprite>("sprite-atlas");
Debug.Log(arrSprites.Length);


foreach (Sprite lvSprite in arrSprites)
{
Debug.Log(lvSprite.name);

}

ChangeImage();

}

// Update is called once per frame
void Update () {

}

// Call this function when button click
public void ChangeImage(){

spriteIndexInArray = spriteIndexInArray < arrSprites.Length - 1 ? spriteIndexInArray + 1 : 0;


Debug.Log ("spriteIndexInArray : " + spriteIndexInArray );

imgImage.sprite = arrSprites[spriteIndexInArray];
txtImageName.text = arrSprites[spriteIndexInArray].name;
}
}

9. Drag-n-drop UI elements to "SpriteAtlasController.cs" script

10. Add OnClick call of method "ChangeImage()" for Button in UI

Hooray!!! :)