RCTSurface: Couple helper functions for Stage

Summary: We need this trivial funcs to unify spinner appearance logic.

Reviewed By: rsnara

Differential Revision: D6367072

fbshipit-source-id: 70e288bc1fed5911828a5f6deaa829597bf8ebff

Author: shergin

Libraries/SurfaceBackedComponent/RCTSurfaceBackedComponent.mm

@@ -55,7 +55,7 @@ + (instancetype)newWithBridge:(RCTBridge *)bridge
                                        options:options];
 
   CKComponent *component;
-  if (options.activityIndicatorComponentFactory == nil || state.surface.stage & RCTSurfaceStageSurfaceDidInitialLayout) {
+  if (options.activityIndicatorComponentFactory == nil || RCTSurfaceStageIsRunning(state.surface.stage)) {
     component = surfaceHostingComponent;
   } else {
     component = [CKOverlayLayoutComponent newWithComponent:surfaceHostingComponent

React/Base/Surface/RCTSurface.mm

@@ -82,7 +82,7 @@ - (instancetype)initWithBridge:(RCTBridge *)bridge
     _stage = RCTSurfaceStageSurfaceDidInitialize;
 
     if (!bridge.loading) {
-      _stage = (RCTSurfaceStage)(_stage | RCTSurfaceStageBridgeDidLoad);
+      _stage = _stage | RCTSurfaceStageBridgeDidLoad;
     }
 
     [self _registerRootViewTag];

React/Base/Surface/RCTSurfaceStage.h

@@ -9,6 +9,8 @@
 
 #import <UIKit/UIKit.h>
 
+#import <React/RCTDefines.h>
+
 /**
  * The stage of the Surface
  */
@@ -22,3 +24,13 @@ typedef NS_OPTIONS(NSInteger, RCTSurfaceStage) {
   RCTSurfaceStageSurfaceDidInitialMounting = 1 << 6,   // UIManager completed the first mounting pass
   RCTSurfaceStageSurfaceDidInvalidate = 1 << 7,        // Surface received `invalidate` message
 };
+
+/**
+ * Returns `YES` if the stage is suitable for displaying normal React Native app.
+ */
+RCT_EXTERN BOOL RCTSurfaceStageIsRunning(RCTSurfaceStage stage);
+
+/**
+ * Returns `YES` if the stage is suitable for displaying activity indicator.
+ */
+RCT_EXTERN BOOL RCTSurfaceStageIsPreparing(RCTSurfaceStage stage);

React/Base/Surface/RCTSurfaceStage.m

@@ -0,0 +1,22 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#import "RCTSurfaceStage.h"
+
+BOOL RCTSurfaceStageIsRunning(RCTSurfaceStage stage) {
+  return
+    (stage & RCTSurfaceStageSurfaceDidInitialLayout) &&
+    !(stage & RCTSurfaceStageSurfaceDidInvalidate);
+}
+
+BOOL RCTSurfaceStageIsPreparing(RCTSurfaceStage stage) {
+  return
+    !(stage & RCTSurfaceStageSurfaceDidInitialLayout) &&
+    !(stage & RCTSurfaceStageSurfaceDidInvalidate);
+}