diff --git a/shell/platform/darwin/macos/framework/Source/FlutterCompositor.h b/shell/platform/darwin/macos/framework/Source/FlutterCompositor.h
index 575742df2c8ef..ce22bb9f54916 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterCompositor.h
+++ b/shell/platform/darwin/macos/framework/Source/FlutterCompositor.h
@@ -49,7 +49,7 @@ class FlutterCompositor {
 
   // Presents the FlutterLayers by updating the FlutterView specified by
   // `view_id` using the layer content. Sets frame_started_ to false.
-  bool Present(uint64_t view_id, const FlutterLayer** layers, size_t layers_count);
+  bool Present(FlutterViewId view_id, const FlutterLayer** layers, size_t layers_count);
 
  private:
   void PresentPlatformViews(FlutterView* default_base_view,
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterCompositor.mm b/shell/platform/darwin/macos/framework/Source/FlutterCompositor.mm
index 96acf4bb2a189..3da1c44edf0c4 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterCompositor.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterCompositor.mm
@@ -37,7 +37,7 @@
   return true;
 }
 
-bool FlutterCompositor::Present(uint64_t view_id,
+bool FlutterCompositor::Present(FlutterViewId view_id,
                                 const FlutterLayer** layers,
                                 size_t layers_count) {
   FlutterView* view = [view_provider_ viewForId:view_id];
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterCompositorTest.mm b/shell/platform/darwin/macos/framework/Source/FlutterCompositorTest.mm
index 4005b176aaf24..f7ac37e01be68 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterCompositorTest.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterCompositorTest.mm
@@ -11,8 +11,6 @@
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterViewProvider.h"
 #import "flutter/testing/testing.h"
 
-extern const uint64_t kFlutterDefaultViewId;
-
 @interface FlutterViewMockProvider : NSObject <FlutterViewProvider> {
   FlutterView* _defaultView;
 }
@@ -32,7 +30,7 @@ - (nonnull instancetype)initWithDefaultView:(nonnull FlutterView*)view {
   return self;
 }
 
-- (nullable FlutterView*)viewForId:(uint64_t)viewId {
+- (nullable FlutterView*)viewForId:(FlutterViewId)viewId {
   if (viewId == kFlutterDefaultViewId) {
     return _defaultView;
   }
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterEngine.mm b/shell/platform/darwin/macos/framework/Source/FlutterEngine.mm
index 3d3c60b69ff45..16e8405a6fcdd 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterEngine.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterEngine.mm
@@ -23,8 +23,6 @@
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterViewController_Internal.h"
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProvider.h"
 
-const uint64_t kFlutterDefaultViewId = 0;
-
 NSString* const kFlutterPlatformChannel = @"flutter/platform";
 
 /**
@@ -88,7 +86,7 @@ @interface FlutterEngine () <FlutterBinaryMessenger>
  */
 @property(nonatomic, strong) NSMutableArray<NSNumber*>* isResponseValid;
 
-- (nullable FlutterViewController*)viewControllerForId:(uint64_t)viewId;
+- (nullable FlutterViewController*)viewControllerForId:(FlutterViewId)viewId;
 
 /**
  * An internal method that adds the view controller with the given ID.
@@ -96,7 +94,7 @@ - (nullable FlutterViewController*)viewControllerForId:(uint64_t)viewId;
  * This method assigns the controller with the ID, puts the controller into the
  * map, and does assertions related to the default view ID.
  */
-- (void)registerViewController:(FlutterViewController*)controller forId:(uint64_t)viewId;
+- (void)registerViewController:(FlutterViewController*)controller forId:(FlutterViewId)viewId;
 
 /**
  * An internal method that removes the view controller with the given ID.
@@ -105,7 +103,7 @@ - (void)registerViewController:(FlutterViewController*)controller forId:(uint64_
  * map. This is an no-op if the view ID is not associated with any view
  * controllers.
  */
-- (void)deregisterViewControllerForId:(uint64_t)viewId;
+- (void)deregisterViewControllerForId:(FlutterViewId)viewId;
 
 /**
  * Shuts down the engine if view requirement is not met, and headless execution
@@ -259,6 +257,8 @@ - (void)requestApplicationTermination:(id)sender
 @interface FlutterEngineRegistrar : NSObject <FlutterPluginRegistrar>
 - (instancetype)initWithPlugin:(nonnull NSString*)pluginKey
                  flutterEngine:(nonnull FlutterEngine*)flutterEngine;
+
+- (NSView*)viewForId:(FlutterViewId)viewId;
 @end
 
 @implementation FlutterEngineRegistrar {
@@ -291,7 +291,7 @@ - (NSView*)view {
   return [self viewForId:kFlutterDefaultViewId];
 }
 
-- (NSView*)viewForId:(uint64_t)viewId {
+- (NSView*)viewForId:(FlutterViewId)viewId {
   FlutterViewController* controller = [_flutterEngine viewControllerForId:viewId];
   if (controller == nil) {
     return nil;
@@ -578,7 +578,7 @@ - (void)loadAOTData:(NSString*)assetsDir {
   }
 }
 
-- (void)registerViewController:(FlutterViewController*)controller forId:(uint64_t)viewId {
+- (void)registerViewController:(FlutterViewController*)controller forId:(FlutterViewId)viewId {
   NSAssert(controller != nil, @"The controller must not be nil.");
   NSAssert(![controller attached],
            @"The incoming view controller is already attached to an engine.");
@@ -588,7 +588,7 @@ - (void)registerViewController:(FlutterViewController*)controller forId:(uint64_
   [_viewControllers setObject:controller forKey:@(viewId)];
 }
 
-- (void)deregisterViewControllerForId:(uint64_t)viewId {
+- (void)deregisterViewControllerForId:(FlutterViewId)viewId {
   FlutterViewController* oldController = [self viewControllerForId:viewId];
   if (oldController != nil) {
     [oldController detachFromEngine];
@@ -602,7 +602,7 @@ - (void)shutDownIfNeeded {
   }
 }
 
-- (FlutterViewController*)viewControllerForId:(uint64_t)viewId {
+- (FlutterViewController*)viewControllerForId:(FlutterViewId)viewId {
   FlutterViewController* controller = [_viewControllers objectForKey:@(viewId)];
   NSAssert(controller == nil || controller.viewId == viewId,
            @"The stored controller has unexpected view ID.");
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterEngineTest.mm b/shell/platform/darwin/macos/framework/Source/FlutterEngineTest.mm
index af2cc140f909f..d7aa813ca2fbf 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterEngineTest.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterEngineTest.mm
@@ -646,7 +646,7 @@ - (nonnull NSView*)createWithViewIdentifier:(int64_t)viewId arguments:(nullable
   @autoreleasepool {
     // Create FVC1.
     viewController1 = [[FlutterViewController alloc] initWithProject:project];
-    EXPECT_EQ(viewController1.viewId, 0ull);
+    EXPECT_EQ(viewController1.viewId, 0ll);
 
     engine = viewController1.engine;
     engine.viewController = nil;
@@ -663,7 +663,7 @@ - (nonnull NSView*)createWithViewIdentifier:(int64_t)viewId arguments:(nullable
 
   engine.viewController = viewController1;
   EXPECT_EQ(engine.viewController, viewController1);
-  EXPECT_EQ(viewController1.viewId, 0ull);
+  EXPECT_EQ(viewController1.viewId, 0ll);
 }
 
 TEST_F(FlutterEngineTest, ManageControllersIfInitiatedByEngine) {
@@ -677,7 +677,7 @@ - (nonnull NSView*)createWithViewIdentifier:(int64_t)viewId arguments:(nullable
 
   @autoreleasepool {
     viewController1 = [[FlutterViewController alloc] initWithEngine:engine nibName:nil bundle:nil];
-    EXPECT_EQ(viewController1.viewId, 0ull);
+    EXPECT_EQ(viewController1.viewId, 0ll);
     EXPECT_EQ(engine.viewController, viewController1);
 
     engine.viewController = nil;
@@ -685,7 +685,7 @@ - (nonnull NSView*)createWithViewIdentifier:(int64_t)viewId arguments:(nullable
     FlutterViewController* viewController2 = [[FlutterViewController alloc] initWithEngine:engine
                                                                                    nibName:nil
                                                                                     bundle:nil];
-    EXPECT_EQ(viewController2.viewId, 0ull);
+    EXPECT_EQ(viewController2.viewId, 0ll);
     EXPECT_EQ(engine.viewController, viewController2);
   }
   // FVC2 is deallocated but FVC1 is retained.
@@ -694,7 +694,7 @@ - (nonnull NSView*)createWithViewIdentifier:(int64_t)viewId arguments:(nullable
 
   engine.viewController = viewController1;
   EXPECT_EQ(engine.viewController, viewController1);
-  EXPECT_EQ(viewController1.viewId, 0ull);
+  EXPECT_EQ(viewController1.viewId, 0ll);
 }
 
 TEST_F(FlutterEngineTest, HandlesTerminationRequest) {
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h b/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h
index 13c47f239ab69..e291094eaa342 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h
+++ b/shell/platform/darwin/macos/framework/Source/FlutterEngine_Internal.h
@@ -135,7 +135,7 @@ typedef NS_ENUM(NSInteger, FlutterAppExitResponse) {
 /**
  * The |FlutterViewController| associated with the given view ID, if any.
  */
-- (nullable FlutterViewController*)viewControllerForId:(uint64_t)viewId;
+- (nullable FlutterViewController*)viewControllerForId:(FlutterViewId)viewId;
 
 /**
  * Informs the engine that the specified view controller's window metrics have changed.
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h b/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h
index 483a858032bc8..1665008d20840 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h
+++ b/shell/platform/darwin/macos/framework/Source/FlutterRenderer.h
@@ -38,12 +38,12 @@
 /**
  * Called by the engine when the given view's buffers should be swapped.
  */
-- (BOOL)present:(uint64_t)viewId texture:(nonnull const FlutterMetalTexture*)texture;
+- (BOOL)present:(FlutterViewId)viewId texture:(nonnull const FlutterMetalTexture*)texture;
 
 /**
  * Creates a Metal texture for the given view with the given size.
  */
-- (FlutterMetalTexture)createTextureForView:(uint64_t)viewId size:(CGSize)size;
+- (FlutterMetalTexture)createTextureForView:(FlutterViewId)viewId size:(CGSize)size;
 
 /**
  * Populates the texture registry with the provided metalTexture.
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterRenderer.mm b/shell/platform/darwin/macos/framework/Source/FlutterRenderer.mm
index d7d2c2fc7d6ac..cf05690f5254c 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterRenderer.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterRenderer.mm
@@ -17,7 +17,7 @@ static FlutterMetalTexture OnGetNextDrawableForDefaultView(FlutterEngine* engine
   // TODO(dkwingsmt): This callback only supports single-view, therefore it only
   // operates on the default view. To support multi-view, we need a new callback
   // that also receives a view ID, or pass the ID via FlutterFrameInfo.
-  uint64_t viewId = kFlutterDefaultViewId;
+  FlutterViewId viewId = kFlutterDefaultViewId;
   CGSize size = CGSizeMake(frameInfo->size.width, frameInfo->size.height);
   return [engine.renderer createTextureForView:viewId size:size];
 }
@@ -27,7 +27,7 @@ static bool OnPresentDrawableOfDefaultView(FlutterEngine* engine,
   // TODO(dkwingsmt): This callback only supports single-view, therefore it only
   // operates on the default view. To support multi-view, we need a new callback
   // that also receives a view ID.
-  uint64_t viewId = kFlutterDefaultViewId;
+  FlutterViewId viewId = kFlutterDefaultViewId;
   return [engine.renderer present:viewId texture:texture];
 }
 
@@ -88,7 +88,7 @@ - (FlutterRendererConfig)createRendererConfig {
 
 #pragma mark - Embedder callback implementations.
 
-- (FlutterMetalTexture)createTextureForView:(uint64_t)viewId size:(CGSize)size {
+- (FlutterMetalTexture)createTextureForView:(FlutterViewId)viewId size:(CGSize)size {
   FlutterView* view = [_viewProvider viewForId:viewId];
   NSAssert(view != nil, @"Can't create texture on a non-existent view 0x%llx.", viewId);
   if (view == nil) {
@@ -98,7 +98,7 @@ - (FlutterMetalTexture)createTextureForView:(uint64_t)viewId size:(CGSize)size {
   return [view.surfaceManager surfaceForSize:size].asFlutterMetalTexture;
 }
 
-- (BOOL)present:(uint64_t)viewId texture:(const FlutterMetalTexture*)texture {
+- (BOOL)present:(FlutterViewId)viewId texture:(const FlutterMetalTexture*)texture {
   FlutterView* view = [_viewProvider viewForId:viewId];
   if (view == nil) {
     return NO;
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterView.h b/shell/platform/darwin/macos/framework/Source/FlutterView.h
index 73425737fbd3a..f581079574bdc 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterView.h
+++ b/shell/platform/darwin/macos/framework/Source/FlutterView.h
@@ -9,6 +9,19 @@
 
 #include <stdint.h>
 
+typedef int64_t FlutterViewId;
+
+/**
+ * The view ID for APIs that don't support multi-view.
+ *
+ * Some single-view APIs will eventually be replaced by their multi-view
+ * variant. During the deprecation period, the single-view APIs will coexist with
+ * and work with the multi-view APIs as if the other views don't exist.  For
+ * backward compatibility, single-view APIs will always operate on the view with
+ * this ID. Also, the first view assigned to the engine will also have this ID.
+ */
+constexpr FlutterViewId kFlutterDefaultViewId = 0ll;
+
 /**
  * Listener for view resizing.
  */
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterViewController.mm b/shell/platform/darwin/macos/framework/Source/FlutterViewController.mm
index 6ae3d5ab2f7f3..f6e9aa3eb957f 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterViewController.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterViewController.mm
@@ -370,6 +370,8 @@ @implementation FlutterViewController {
   FlutterDartProject* _project;
 
   std::shared_ptr<flutter::AccessibilityBridgeMac> _bridge;
+
+  FlutterViewId _id;
 }
 
 @synthesize viewId = _viewId;
@@ -510,7 +512,7 @@ - (void)setBackgroundColor:(NSColor*)color {
   [_flutterView setBackgroundColor:_backgroundColor];
 }
 
-- (uint64_t)viewId {
+- (FlutterViewId)viewId {
   NSAssert([self attached], @"This view controller is not attched.");
   return _viewId;
 }
@@ -539,7 +541,7 @@ - (void)notifySemanticsEnabledChanged {
   return _bridge;
 }
 
-- (void)attachToEngine:(nonnull FlutterEngine*)engine withId:(uint64_t)viewId {
+- (void)attachToEngine:(nonnull FlutterEngine*)engine withId:(FlutterViewId)viewId {
   NSAssert(_engine == nil, @"Already attached to an engine %@.", _engine);
   _engine = engine;
   _viewId = viewId;
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterViewController_Internal.h b/shell/platform/darwin/macos/framework/Source/FlutterViewController_Internal.h
index 467bf644c9e74..62801f9bce739 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterViewController_Internal.h
+++ b/shell/platform/darwin/macos/framework/Source/FlutterViewController_Internal.h
@@ -21,7 +21,7 @@
  * If the view controller is unattached (see FlutterViewController#attached),
  * reading this property throws an assertion.
  */
-@property(nonatomic, readonly) uint64_t viewId;
+@property(nonatomic, readonly) FlutterViewId viewId;
 
 // The FlutterView for this view controller.
 @property(nonatomic, readonly, nullable) FlutterView* flutterView;
@@ -43,7 +43,7 @@
  *
  * This method is called by FlutterEngine.
  */
-- (void)attachToEngine:(nonnull FlutterEngine*)engine withId:(uint64_t)viewId;
+- (void)attachToEngine:(nonnull FlutterEngine*)engine withId:(FlutterViewId)viewId;
 
 /**
  * Reset the `engine` and `id` of this controller.
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProvider.mm b/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProvider.mm
index 95c3aa53e0ee5..eabf7e13d938b 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProvider.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProvider.mm
@@ -22,7 +22,7 @@ - (instancetype)initWithEngine:(FlutterEngine*)engine {
   return self;
 }
 
-- (nullable FlutterView*)viewForId:(uint64_t)viewId {
+- (nullable FlutterView*)viewForId:(FlutterViewId)viewId {
   return [_engine viewControllerForId:viewId].flutterView;
 }
 
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProviderTest.mm b/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProviderTest.mm
index 86c94a70caa60..403639b79e62a 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProviderTest.mm
+++ b/shell/platform/darwin/macos/framework/Source/FlutterViewEngineProviderTest.mm
@@ -25,9 +25,9 @@
   OCMStub([mockEngine viewControllerForId:0])
       .ignoringNonObjectArgs()
       .andDo(^(NSInvocation* invocation) {
-        uint64_t viewId;
+        FlutterViewId viewId;
         [invocation getArgument:&viewId atIndex:2];
-        if (viewId == 0 /* kFlutterDefaultViewId */) {
+        if (viewId == kFlutterDefaultViewId) {
           if (mockFlutterViewController != nil) {
             [invocation setReturnValue:&mockFlutterViewController];
           }
diff --git a/shell/platform/darwin/macos/framework/Source/FlutterViewProvider.h b/shell/platform/darwin/macos/framework/Source/FlutterViewProvider.h
index 9548b7afab1b8..0e78c2bdf0a2d 100644
--- a/shell/platform/darwin/macos/framework/Source/FlutterViewProvider.h
+++ b/shell/platform/darwin/macos/framework/Source/FlutterViewProvider.h
@@ -4,8 +4,6 @@
 
 #import "flutter/shell/platform/darwin/macos/framework/Source/FlutterView.h"
 
-extern const uint64_t kFlutterDefaultViewId;
-
 /**
  * An interface to query FlutterView.
  *
@@ -20,6 +18,6 @@ extern const uint64_t kFlutterDefaultViewId;
  *
  * Returns nil if the ID is invalid.
  */
-- (nullable FlutterView*)viewForId:(uint64_t)id;
+- (nullable FlutterView*)viewForId:(FlutterViewId)id;
 
 @end