Version: 2017.2
public string GetInfoString ();



You will also have to implement HasPreviewGUI and OnPreviewGUI in addition to this method. The default implementation just returns an empty string, which disables the feature.

Note: Inspector previews are limited to the primary editor of persistent objects (assets), e.g., GameObjectInspector, MaterialEditor, TextureInspector. This means that it is currently not possible for a component to have its own inspector preview.