/// Must be drawn before DefaultProperty in order to receive input
public static void DrawSelectionButtonForManagedReference(this SerializedProperty property,
Rect position, IEnumerable <Func <Type, bool> > filters = null)
{
//var backgroundColor = new Color(0f, 0.7f, 0.7f, 1f);
var backgroundColor = new Color(0.1f, 0.45f, 0.8f, 1f);
//var backgroundColor = GUI.backgroundColor;
var buttonPosition = position;
buttonPosition.x += EditorGUIUtility.labelWidth + 1 * EditorGUIUtility.standardVerticalSpacing;
buttonPosition.width = position.width - EditorGUIUtility.labelWidth - 1 * EditorGUIUtility.standardVerticalSpacing;
buttonPosition.height = EditorGUIUtility.singleLineHeight;
var storedIndent = EditorGUI.indentLevel;
EditorGUI.indentLevel = 0;
var storedColor = GUI.backgroundColor;
GUI.backgroundColor = backgroundColor;
var names = SerializeReferenceTypeNameUtility.GetSplitNamesFromTypename(property.managedReferenceFullTypename);
var className = string.IsNullOrEmpty(names.ClassName) ? "Null (Assign)" : names.ClassName;
var assemblyName = names.AssemblyName;
if (GUI.Button(buttonPosition, new GUIContent(className, className + " ( " + assemblyName + " )")))
{
property.ShowContextMenuForManagedReference(filters);
}
GUI.backgroundColor = storedColor;
EditorGUI.indentLevel = storedIndent;
}
/// Purpose.
/// This is generic selection menu.
/// Filtering.
/// You can add substring filter here to filter by search string.
/// As well ass type or interface restrictions.
/// As well as any custom restriction that is based on input type.
/// And it will be performed on each Appropriate type found by TypeCache.
public static void ShowContextMenuForManagedReference(this SerializedProperty property, IEnumerable <Func <Type, bool> > filters = null)
{
var context = new GenericMenu();
FillContextMenu();
context.ShowAsContext();
void FillContextMenu()
{
context.AddItem(new GUIContent("Null"), false, MakeNull);
var realPropertyType = SerializeReferenceTypeNameUtility.GetRealTypeFromTypename(property.managedReferenceFieldTypename);
if (realPropertyType == null)
{
Debug.LogError("Can not get type from");
return;
}
var types = TypeCache.GetTypesDerivedFrom(realPropertyType);
foreach (var type in types)
{
// Skips unity engine Objects (because they are not serialized by SerializeReference)
if (type.IsSubclassOf(typeof(UnityEngine.Object)))
{
continue;
}
// Skip abstract classes because they should not be instantiated
if (type.IsAbstract)
{
continue;
}
if (FilterTypeByFilters(filters, type) == false)
{
continue;
}
AddContextMenu(type, context);
}
void MakeNull()
{
property.serializedObject.Update();
property.managedReferenceValue = null;
property.serializedObject.ApplyModifiedPropertiesWithoutUndo(); // undo is bugged for now
}
void AddContextMenu(Type type, GenericMenu genericMenuContext)
{
var assemblyName = type.Assembly.ToString().Split('(', ',')[0];
var entryName = type.Name + " ( " + assemblyName + " )";
genericMenuContext.AddItem(new GUIContent(entryName), false, AssignNewInstanceOfType, type);
}
void AssignNewInstanceOfType(object typeAsObject)
{
var type = (Type)typeAsObject;
var instance = Activator.CreateInstance(type);
property.serializedObject.Update();
property.managedReferenceValue = instance;
property.serializedObject.ApplyModifiedPropertiesWithoutUndo(); // undo is bugged for now
}
bool FilterTypeByFilters(IEnumerable <Func <Type, bool> > filters_, Type type) =>
filters_.All(f => f.Invoke(type));
}
}
