[video_player] fix: add missing isPlaybackLikelyToKeepUp check. (#3826)

When watching a live stream, if the playback buffers but the AVPlayerItem is likely to keep up, it is necessary to recheck AVPlayerItem.isPlaybackLikelyToKeepUp. If isPlaybackLikelyToKeepUp, a bufferingEnd event should be immediately triggered. I am encountering an issue with my product where, when watching a live stream, if I seek to the latest time, it continuously `bufferingStart` and does not come to an `bufferingEnd`.

packages/video_player/video_player_avfoundation/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.4.8
+
+* Fixes missing `isPlaybackLikelyToKeepUp` check for iOS video player `bufferingEnd` event and `bufferingStart` event.
+
 ## 2.4.7
 
 * Updates minimum supported SDK version to Flutter 3.3/Dart 2.18.

packages/video_player/video_player_avfoundation/example/ios/RunnerTests/VideoPlayerTests.m

@@ -207,6 +207,52 @@
   [self waitForExpectationsWithTimeout:30.0 handler:nil];
 }
 
+- (void)testBufferingStateFromPlayer {
+  NSObject<FlutterPluginRegistry> *registry =
+      (NSObject<FlutterPluginRegistry> *)[[UIApplication sharedApplication] delegate];
+  NSObject<FlutterPluginRegistrar> *registrar =
+      [registry registrarForPlugin:@"testLiveStreamBufferEndFromPlayer"];
+  FLTVideoPlayerPlugin *videoPlayerPlugin =
+      (FLTVideoPlayerPlugin *)[[FLTVideoPlayerPlugin alloc] initWithRegistrar:registrar];
+
+  FlutterError *error;
+  [videoPlayerPlugin initialize:&error];
+  XCTAssertNil(error);
+
+  FLTCreateMessage *create = [FLTCreateMessage
+      makeWithAsset:nil
+                uri:@"https://flutter.github.io/assets-for-api-docs/assets/videos/bee.mp4"
+        packageName:nil
+         formatHint:nil
+        httpHeaders:@{}];
+  FLTTextureMessage *textureMessage = [videoPlayerPlugin create:create error:&error];
+  XCTAssertNil(error);
+  XCTAssertNotNil(textureMessage);
+  FLTVideoPlayer *player = videoPlayerPlugin.playersByTextureId[textureMessage.textureId];
+  XCTAssertNotNil(player);
+  AVPlayer *avPlayer = player.player;
+  [avPlayer play];
+
+  [player onListenWithArguments:nil
+                      eventSink:^(NSDictionary<NSString *, id> *event) {
+                        if ([event[@"event"] isEqualToString:@"bufferingEnd"]) {
+                          XCTAssertTrue(avPlayer.currentItem.isPlaybackLikelyToKeepUp);
+                        }
+
+                        if ([event[@"event"] isEqualToString:@"bufferingStart"]) {
+                          XCTAssertFalse(avPlayer.currentItem.isPlaybackLikelyToKeepUp);
+                        }
+                      }];
+  XCTestExpectation *bufferingStateExpectation =
+      [self expectationWithDescription:@"bufferingState"];
+  NSTimeInterval timeout = 10;
+  dispatch_time_t delay = dispatch_time(DISPATCH_TIME_NOW, timeout * NSEC_PER_SEC);
+  dispatch_after(delay, dispatch_get_main_queue(), ^{
+    [bufferingStateExpectation fulfill];
+  });
+  [self waitForExpectationsWithTimeout:timeout + 1 handler:nil];
+}
+
 - (void)testVideoControls {
   NSObject<FlutterPluginRegistry> *registry =
       (NSObject<FlutterPluginRegistry> *)[[UIApplication sharedApplication] delegate];

packages/video_player/video_player_avfoundation/ios/Classes/FLTVideoPlayerPlugin.m

@@ -72,8 +72,6 @@ static void *statusContext = &statusContext;
 static void *presentationSizeContext = &presentationSizeContext;
 static void *durationContext = &durationContext;
 static void *playbackLikelyToKeepUpContext = &playbackLikelyToKeepUpContext;
-static void *playbackBufferEmptyContext = &playbackBufferEmptyContext;
-static void *playbackBufferFullContext = &playbackBufferFullContext;
 static void *rateContext = &rateContext;
 
 @implementation FLTVideoPlayer
@@ -108,14 +106,6 @@ static void *rateContext = &rateContext;
          forKeyPath:@"playbackLikelyToKeepUp"
             options:NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew
             context:playbackLikelyToKeepUpContext];
-  [item addObserver:self
-         forKeyPath:@"playbackBufferEmpty"
-            options:NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew
-            context:playbackBufferEmptyContext];
-  [item addObserver:self
-         forKeyPath:@"playbackBufferFull"
-            options:NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew
-            context:playbackBufferFullContext];
 
   // Add observer to AVPlayer instead of AVPlayerItem since the AVPlayerItem does not have a "rate"
   // property
@@ -330,19 +320,15 @@ NS_INLINE UIViewController *rootViewController(void) {
       [self updatePlayingState];
     }
   } else if (context == playbackLikelyToKeepUpContext) {
+    [self updatePlayingState];
     if ([[_player currentItem] isPlaybackLikelyToKeepUp]) {
-      [self updatePlayingState];
       if (_eventSink != nil) {
         _eventSink(@{@"event" : @"bufferingEnd"});
       }
-    }
-  } else if (context == playbackBufferEmptyContext) {
-    if (_eventSink != nil) {
-      _eventSink(@{@"event" : @"bufferingStart"});
-    }
-  } else if (context == playbackBufferFullContext) {
-    if (_eventSink != nil) {
-      _eventSink(@{@"event" : @"bufferingEnd"});
+    } else {
+      if (_eventSink != nil) {
+        _eventSink(@{@"event" : @"bufferingStart"});
+      }
     }
   } else if (context == rateContext) {
     // Important: Make sure to cast the object to AVPlayer when observing the rate property,
@@ -528,8 +514,6 @@ NS_INLINE UIViewController *rootViewController(void) {
   [currentItem removeObserver:self forKeyPath:@"presentationSize"];
   [currentItem removeObserver:self forKeyPath:@"duration"];
   [currentItem removeObserver:self forKeyPath:@"playbackLikelyToKeepUp"];
-  [currentItem removeObserver:self forKeyPath:@"playbackBufferEmpty"];
-  [currentItem removeObserver:self forKeyPath:@"playbackBufferFull"];
 
   [self.player replaceCurrentItemWithPlayerItem:nil];
   [[NSNotificationCenter defaultCenter] removeObserver:self];

packages/video_player/video_player_avfoundation/pubspec.yaml

@@ -2,7 +2,7 @@ name: video_player_avfoundation
 description: iOS implementation of the video_player plugin.
 repository: https://github.com/flutter/packages/tree/main/packages/video_player/video_player_avfoundation
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+video_player%22
-version: 2.4.7
+version: 2.4.8
 
 environment:
   sdk: ">=2.18.0 <4.0.0"