[video_player][iOS] Playback speed resets when seeking

[guoyiheng]

Description :
When you set double speed playback, dragging the progress bar will invalidate the double speed, but the displayed double speed will not change.

Step:

1. Set double speed playback.
2. Tap the progress bar to seekTo
3. speed is wired.

Example: https://github.com/flutter/plugins/tree/master/packages/video_player/video_player/example

flutter doctor
[✓] Flutter (Channel stable, 1.22.4, on macOS 11.0.1 20B29 darwin-x64, locale zh-Hans-CN)
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
[✓] Xcode - develop for iOS and macOS (Xcode 12.2)
[!] Android Studio (version 4.1)
✗ Flutter plugin not installed; this adds Flutter specific functionality.
✗ Dart plugin not installed; this adds Dart specific functionality.
[✓] VS Code (version 1.51.1)
[✓] Connected device (1 available)

! Doctor found issues in 1 category.

[pedromassangocode]

Hi @mypridelife
I cannot reproduce this with the latest version of the plugin.

flutter doctor -v

[✓] Flutter (Channel stable, 1.22.4, on Mac OS X 10.15.7 19H2 darwin-x64, locale en)
    • Flutter version 1.22.4 at /Users/pedromassango/dev/SDKs/flutter_stable
    • Framework revision 1aafb3a8b9 (13 days ago), 2020-11-13 09:59:28 -0800
    • Engine revision 2c956a31c0
    • Dart version 2.10.4

[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
    • Android SDK at /Users/pedromassango/Library/Android/sdk
    • Platform android-30, build-tools 30.0.2
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 12.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 12.1, Build version 12A7403
    • CocoaPods version 1.9.3

[!] Android Studio (version 4.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b3-6915495)

[✓] IntelliJ IDEA Community Edition (version 2020.2.3)
    • IntelliJ at /Applications/IntelliJ IDEA CE.app
    • Flutter plugin installed
    • Dart plugin version 202.8070

[✓] VS Code (version 1.51.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.16.0

[✓] Connected device (1 available)
    • iPhone 12 Pro Max (mobile) • ECCF5C4A-8BEC-411D-B23E-85A836C3847E • ios • com.apple.CoreSimulator.SimRuntime.iOS-14-1 (simulator)

! Doctor found issues in 1 category.

[guoyiheng]

The sample video is too short to reproduce. Try a long video or: http://cdn.binfenyingyu.com/wx_class_file_1606440527690?sign=f0abbab3545ec5b01dbc8b3140b608dc&t=5fc990e9
If you don’t distinguish the speed, you can pause and play after seekTo. And pause and play after seekTo also can reproduce this strange speed phenomenon. @pedromassangocode

[guoyiheng]

FLTVideoPlayerPlugin.m

- (void)seekTo:(FLTPositionMessage*)input error:(FlutterError**)error {
  FLTVideoPlayer* player = _players[input.textureId];
  [player seekTo:[input.position intValue]];
}

I found that the key point is completionHandler

- (void)seekTo:(int)location {
  [_player seekToTime:CMTimeMake(location, 1000)
      toleranceBefore:kCMTimeZero
       toleranceAfter:kCMTimeZero
    completionHandler:^(BOOL finished) {
      NSLog(@"seekTo...end, finished = %d",finished);
  }];
    NSLog(@"seekTo-location = %d",location);
}

Since seekTo is not completed, we set the double speed. When the seekTo is completed, the speed will be set back to 1.0, causing the set speed to be invalid.

[pedromassangocode]

Reproducible with the latest version of the plugin (video_player: ^1.0.1).

flutter doctor -v

[✓] Flutter (Channel stable, 1.22.4, on Mac OS X 10.15.7 19H2 darwin-x64, locale
    en)
    • Flutter version 1.22.4 at /Users/pedromassango/dev/SDKs/flutter_stable
    • Framework revision 1aafb3a8b9 (2 weeks ago), 2020-11-13 09:59:28 -0800
    • Engine revision 2c956a31c0
    • Dart version 2.10.4

 
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
    • Android SDK at /Users/pedromassango/Library/Android/sdk
    • Platform android-30, build-tools 30.0.2
    • Java binary at: /Applications/Android
      Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build
      1.8.0_242-release-1644-b3-6915495)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 12.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 12.1, Build version 12A7403
    • CocoaPods version 1.9.3

[!] Android Studio (version 4.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
    • Java version OpenJDK Runtime Environment (build
      1.8.0_242-release-1644-b3-6915495)

[✓] IntelliJ IDEA Community Edition (version 2020.2.3)
    • IntelliJ at /Applications/IntelliJ IDEA CE.app
    • Flutter plugin installed
    • Dart plugin version 202.8070

[✓] VS Code (version 1.51.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.16.0

[✓] Connected device (1 available)
    • iPhone 12 Pro Max (mobile) • ECCF5C4A-8BEC-411D-B23E-85A836C3847E • ios •
      com.apple.CoreSimulator.SimRuntime.iOS-14-1 (simulator)

! Doctor found issues in 1 category.