EditorGUIUtility.ShowObjectPicker
static function ShowObjectPicker(obj: Object, allowSceneObjects: bool, searchFilter: string, controlID: int): void;
static void ShowObjectPicker(Object obj, bool allowSceneObjects, string searchFilter, int controlID);
static def ShowObjectPicker(obj as Object, allowSceneObjects as bool, searchFilter as string, controlID as int) as void
Parameters

obj The object to be selected by default.
allowSceneObjects Is selection of scene objects allowed, or should it only show assets.
searchFilter Default search filter to apply.
controlID The id of the control to set. This is useful if you are showing more than one of these. You can get the value at a later time.
Description

Show the object picker from code.

Once the user interacts with the Object Picker, it will respond by sending ExecuteCommand events back to the calling OnGUI that called this function. The messages are:

ObjectSelectorUpdated - The selected object was changed. The selected object can be read by calling GetObjectPickerObject ObjectSelectorClosed - The user closed the object picker.