From f72695af6bd5027dbc70fb7f628977fb1e30843c Mon Sep 17 00:00:00 2001
From: luckysmg <2539699336@qq.com>
Date: Sat, 20 Nov 2021 14:26:25 +0800
Subject: [PATCH 1/2] [iOS] Fix keyboard inset is not correct when presenting
 and native ViewController on FlutterViewController

---
 .../darwin/ios/framework/Source/FlutterViewController.mm     | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/shell/platform/darwin/ios/framework/Source/FlutterViewController.mm b/shell/platform/darwin/ios/framework/Source/FlutterViewController.mm
index 4f7125f8248dc..7f5ebd1e81932 100644
--- a/shell/platform/darwin/ios/framework/Source/FlutterViewController.mm
+++ b/shell/platform/darwin/ios/framework/Source/FlutterViewController.mm
@@ -1200,9 +1200,10 @@ - (void)startKeyBoardAnimation:(NSTimeInterval)duration {
       }
       completion:^(BOOL finished) {
         if (self.displayLink == currentDisplayLink) {
+          // Indicates the displaylink captured by this block is the original one,which also
+          // indicates the animation has not been interrupted from its beginning. Moreover,indicates
+          // the animation is over and there is no more animation about to exectute.
           [self invalidateDisplayLink];
-        }
-        if (finished) {
           [self removeKeyboardAnimationView];
           [self ensureViewportMetricsIsCorrect];
         }

From ac4fa44a9d96f0acc2acd17f01e8cb85875852a6 Mon Sep 17 00:00:00 2001
From: Jenn Magder <magder@google.com>
Date: Mon, 22 Nov 2021 11:11:20 -0800
Subject: [PATCH 2/2] Add viewport update unit test

---
 .../ios/framework/Source/FlutterViewControllerTest.mm     | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/shell/platform/darwin/ios/framework/Source/FlutterViewControllerTest.mm b/shell/platform/darwin/ios/framework/Source/FlutterViewControllerTest.mm
index 2c462e479c56d..0bb8346572891 100644
--- a/shell/platform/darwin/ios/framework/Source/FlutterViewControllerTest.mm
+++ b/shell/platform/darwin/ios/framework/Source/FlutterViewControllerTest.mm
@@ -173,9 +173,17 @@ - (void)testkeyboardWillChangeFrameWillStartKeyboardAnimation {
                     @"UIKeyboardAnimationDurationUserInfoKey" : [NSNumber numberWithDouble:0.25],
                     @"UIKeyboardIsLocalUserInfoKey" : [NSNumber numberWithBool:isLocal]
                   }];
+
+  XCTestExpectation* expectation = [self expectationWithDescription:@"update viewport"];
+  OCMStub([mockEngine updateViewportMetrics:flutter::ViewportMetrics()])
+      .ignoringNonObjectArgs()
+      .andDo(^(NSInvocation* invocation) {
+        [expectation fulfill];
+      });
   id viewControllerMock = OCMPartialMock(viewController);
   [viewControllerMock keyboardWillChangeFrame:notification];
   OCMVerify([viewControllerMock startKeyBoardAnimation:0.25]);
+  [self waitForExpectationsWithTimeout:5.0 handler:nil];
 }
 
 - (void)testEnsureViewportMetricsWillInvokeAndDisplayLinkWillInvalidateInViewDidDisappear {