UnityEditor: Drag and Drop Prefab Preview in Scene View

This tutorial teaches you how to display a preview of a prefab in the Scene view of Unity Editor when you drag and drop it. This feature enhances your workflow by providing instant visual feedback.

Steps:

1. Create a New Script: Create a new C# script file named 'PrefabPreview' (or any name you prefer) within your Unity project.

2. Implement the Code: Paste the following code into the script:

using UnityEditor;
using UnityEngine;

[CustomEditor(typeof(Prefab))]
public class PrefabPreview : Editor
{
    private GameObject _previewObject;

    public override bool HasPreviewGUI()
    {
        return true;
    }

    public override void OnPreviewGUI(Rect r, GUIStyle background)
    {
        if (_previewObject == null)
        {
            _previewObject = (target as Prefab).gameObject;
        }

        if (_previewObject != null)
        {
            EditorGUI.DrawPreviewTexture(r, _previewObject.GetComponent<SpriteRenderer>().sprite.texture);
        }
    }
}

3. Add Script to Editor Folder: Place the 'PrefabPreview.cs' script in your Unity project's 'Assets/Editor' folder. This ensures the script is recognized by the Editor.

4. Test the Preview: Now, drag a prefab from your Project window into the Scene view. You should see a preview image of the prefab being displayed.

Important Note: This custom editor functionality only works within Unity Editor and has no effect on your game's runtime behavior.