How to create custom editor script only for one field of an object and leave the rest default in Unity?

Question

I have a script attached to a game object. The script has many public fields and I'm satisfied with how Unity displays most of the fields for editing in the Editor. Except for a few. I'd like to write a complex custom editor script for those fields and leave the rest as is - public and visible in the Editor. I don't want to write lots of extra code to mimic what the editor does so far.

The perfect scenario would be to be able to define a custom editor script for a certain type (the type is not derived from MonoBehavior and cannot be). If a field of that type is public in any script attached to a GO I'd like the Editor to display it the way I've defined.

Answer 1

In your MonoBehavior script, you can use [HideInInspector] to hide your variable.

public class GameObjectScript: MonoBehaviour
{
    public int randomInt;

    [HideInInspector]
    public string name;
}

---

You can edit your Inspector view by creating an editor script for GameObjectScript that inherits from Editor.

[CustomEditor(typeof(GameObjectScript))]
public class GameObjectScriptEditor: Editor
{

    GameObjectScript myScript;

    public override void OnInspectorGUI()
    {
        DrawDefaultInspector(); //Drawing the default inspector except the one you hide.
                               //Which is only int randomInt

        myScript.name = EditorGUILayout.TextField("My Name: ", myScript.name); //Draw whatever you want in the inspector
    }
}

Please note to place the GameObjectScriptEditor into "Asset/Script/Editor". You can read more in the Unity documentation.