Edit chosen material in the inspector for custom editor.

[TheOrangeMan]

So when an object has a mesh renderer with a material selected, you can edit the material in the same inspector window. Is there anyway to do this with a custom editor?

[Xaurrien]

Hi, I know this topic is old but I think I have a nice way to achieve this with shader selection.
I use a MaterialEditor with the following methods: MaterialEditor.DrawHeader () and MaterialEditor.OnInspectorGUI ().

Example code:

using UnityEditor;

[CustomEditor(typeof(MyScript))]
public class MyScriptEditor : Editor
{
	private MyScript _myScript;

	// We need to use and to call an instnace of the default MaterialEditor
	private MaterialEditor _materialEditor; 

	void OnEnable ()
	{
		_myScript = (MyScript)target;

		if (_myScript.material != null) {
			// Create an instance of the default MaterialEditor
			_materialEditor = (MaterialEditor)CreateEditor (_myScript.material);
		}
	}

	public override void OnInspectorGUI ()
	{
		EditorGUI.BeginChangeCheck ();

		// Draw the material field of MyScript
		EditorGUILayout.PropertyField (serializedObject.FindProperty ("material"));

		if (EditorGUI.EndChangeCheck ()) {
			serializedObject.ApplyModifiedProperties (); 

			if (_materialEditor != null) {
				// Free the memory used by the previous MaterialEditor
				DestroyImmediate (_materialEditor);
			}

			if (_myScript.material != null) {
				// Create a new instance of the default MaterialEditor
				_materialEditor = (MaterialEditor)CreateEditor (_myScript.material);

			}
		}


		if (_materialEditor != null) {
			// Draw the material's foldout and the material shader field
			// Required to call _materialEditor.OnInspectorGUI ();
			_materialEditor.DrawHeader (); 
		
			//  We need to prevent the user to edit Unity default materials
			bool isDefaultMaterial = !AssetDatabase.GetAssetPath (_myScript.material).StartsWith ("Assets");

			using (new EditorGUI.DisabledGroupScope(isDefaultMaterial)) {

				// Draw the material properties
				// Works only if the foldout of _materialEditor.DrawHeader () is open
				_materialEditor.OnInspectorGUI (); 
			}
		}
	}

	void OnDisable ()
	{
		if (_materialEditor != null) {
			// Free the memory used by default MaterialEditor
			DestroyImmediate (_materialEditor);
		}
	}
}

[numberkruncher]

With the new Unity 4 Editor.CreateEditor class you can in fact render a preview interface as well. Here is a simple demonstration:

using UnityEngine;
using UnityEditor;

class MaterialEditorWindow : EditorWindow {

	[MenuItem("Window/Material Editor Test")]
	static void ShowWindow() {
		GetWindow<MaterialEditorWindow>("Material Editor Test");
	}

	Material mat;
	Editor matEditor;

	void OnGUI() {
		mat = EditorGUILayout.ObjectField(mat, typeof(Material)) as Material;
		if (mat != null) {
			if (matEditor == null)
				matEditor = Editor.CreateEditor(mat);

			matEditor.OnPreviewGUI(GUILayoutUtility.GetRect(200, 300), EditorStyles.whiteLabel);
		}
	}

}