position	Rectangle on the screen to use for the field.
label	Optional label in front of the field.
obj	The object the field shows.
objType	The type of the objects that can be assigned.
allowSceneObjects	Allow assigning scene objects. See Description for more info.

Returns
Object The object that has been set by the user.

Make an object field. You can assign objects either by drag and drop objects or by selecting an object using the Object Picker.

Ensure that the allowSceneObjects parameter is false if the object reference is stored as part of an asset, since assets can't store references to objects in a scene.
If the ObjectField is part of a custom Editor for a script component, use EditorUtility.IsPersistent() to check if the component is on an asset or a scene object.
See example in Editor class.

Object field in an Editor Window.

	//Select the dependencies of the found GameObject
	
	class EditorGUIObjectField extends EditorWindow {
		
		var obj : GameObject = null;
		
		@MenuItem("Examples/Select Dependencies")
		static function Init () {
			var window = GetWindow(EditorGUIObjectField);
			window.position = Rect(0, 0, 250, 80);
			window.Show();
		}
		
		function OnInspectorUpdate () {
			Repaint ();
		}
	
		function OnGUI () {		
			obj = EditorGUI.ObjectField(Rect(3,3,position.width - 6, 20),
					"Find Dependency",
					obj,
					GameObject);
			
			if (obj)	{	
				if (GUI.Button(Rect(3,25,position.width - 6, 20), "Check Dependencies"))
					Selection.objects = EditorUtility.CollectDependencies ([obj]);
			} else {
				EditorGUI.LabelField (Rect (3, 25, position.width - 6, 20),
					"Missing:", 
					"Select an object first");
			}
		}
	}