2 files changed, 2 insertions, 1 deletions
diff --git a/src/fields/Document.ts b/src/fields/Document.ts
index 5c0a9caf0..ef759615b 100644
--- a/src/fields/Document.ts
+++ b/src/fields/Document.ts
@@ -32,7 +32,7 @@ export class Document extends Field {
         return field;
     }
 
-    GetFieldT<T extends Field = Field>(key: Key, ctor: { new(): T }, ignoreProto: boolean = false): Opt<T> {
+    GetFieldT<T extends Field = Field>(key: Key, ctor: { new(...args: any[]): T }, ignoreProto: boolean = false): Opt<T> {
         return Cast(this.GetField(key, ignoreProto), ctor);
     }
 
diff --git a/src/fields/Key.ts b/src/fields/Key.ts
index 4da800fac..5cd43f55e 100644
--- a/src/fields/Key.ts
+++ b/src/fields/Key.ts
@@ -41,6 +41,7 @@ export namespace KeyStore {
     export const Scale = new Key("Scale");
     export const Width = new Key("Width");
     export const Height = new Key("Height");
+    export const ZIndex = new Key("ZIndex");
     export const Data = new Key("Data");
     export const Layout = new Key("Layout");
     export const LayoutKeys = new Key("LayoutKeys");