public override void OnInspectorGUI()
            {
                serializedObject.Update();

                ShapeKeyMorphSO morph = (ShapeKeyMorphSO)serializedObject.targetObject;
                Mesh            m     = (Mesh)m_propMesh.objectReferenceValue;

                EditorGUILayout.BeginHorizontal();
                {
                    GUILayout.Label("Morph Name:");
                    GUILayout.Space(20f);

                    string morphName = m_propName.stringValue;
                    if (EUtil.StringField("MorphName", ref morphName))
                    {
                        m_propName.stringValue = morphName;
                        _ChangeAssetNameIfNeeded();
                    }
                }
                EditorGUILayout.EndHorizontal();

                EditorGUILayout.ObjectField(new GUIContent("Working Mesh", "The mesh on which this morph is applied"),
                                            m, typeof(Mesh), true);

                EditorGUILayout.HelpBox(
                    string.Format("vertex: {0},  {1},  {2}", m.vertexCount,
                                  morph.HasNormals ? "normals" : "NO normals",
                                  morph.HasTangents ? "tangents" : "NO tangents"),
                    MessageType.Info);

                // show each shapeKeyData
                for (int i = 0; i < morph.ShapeKeyCnt; ++i)
                {
                    _DrawShapeKeyData(morph, i);
                }

                // add new shapeKeyData button
                GUILayout.BeginHorizontal();
                {
                    GUILayout.Space(30f);
                    if (GUILayout.Button("Add New Shape Key"))
                    {
                        Undo.RecordObject(morph, "ShapeKeyMorphSO inspector");
                        morph.AddNewShapeKeyByMeshCurrentData();
                    }
                    GUILayout.Space(30f);
                }
                GUILayout.EndHorizontal();

                serializedObject.ApplyModifiedProperties();
            }