"Enqueue Next" item displays on Play queue incorrectly

[Naginipython]

Checklist

• I am able to reproduce the bug with the latest version.
• I made sure that there are no existing issues - open or closed - which I could contribute my information to.
• I have read the FAQ and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• This issue contains only one bug.
• I have read and understood the contribution guidelines.

Affected version

0.24.1

Steps to reproduce the bug

1. Take an existing playlist of videos
2. Press 'Play All' at the top
3. Press 'Background' on video
4. Find any other video, long-click and press 'Enqueue Next'
5. Press either the 'Play Queue' button near the play button, or the music notification
6. The video that was enqueued will appear 2 videos after current video, however, if the current video ends, is fast-forwarded or pressed, the video that was enqueued will correctly play next and update the tags. Yet, also still appear as the next video, to be correctly updated once it's turn is up.

Expected behavior

Enqueue Next should display the item in the Play queue next. It currently DOES play the video next, but display isn't correct.

Actual behavior

Play Queue displays incorrectly

Screenshots/Screen recordings

Interestingly, I made a different recording that found another Play Queue-related display issue. I will upload both. The one with anime has the different yet similar issue

screen-20230111-204703.1.mp4

screen-20230111-204455.1.mp4

Logs

No response

Affected Android/Custom ROM version

Android 13 (Rooted)

Affected device model

Pixel 5

Additional information

No response

[vomindoraan]

Can confirm, I've been experiencing this bug since v0.24.0, which is why I'm still using v0.23.3 on my phone.

[vomindoraan]

This issue is still happening on v0.25.1 whenever I try to use Enqueue next while streams are playing in the background. Here is a screen recording:

Screenrecorder-2023-04-25-21-29-00-586.mp4

As you can see, the stream I enqueued to play next seems to get shifted down and replaced by the last stream in the queue. However, this appears to be purely visual, as moving to the next item in the list plays the actual stream I enqueued. Therefore, it looks like there's a discrepancy between what is displayed to the user and the underlying list of streams.

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Other times, using Enqueue next seems to add the stream twice; however, this is again purely visual. You can see this behavior in the following screen recording when I start playing a fresh playlist and then try enqueuing a video from search results as the next stream:

Screenrecorder-2023-04-25-21-46-43-721.mp4

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Finally, the regular Enqueue button that adds a stream to the end of the queue works fine and does not cause any ordering issues: screen recording

[vomindoraan]

Still experiencing this issue. Could anyone give me any pointers as to which files I should look into if I wanted to contribute a fix for this issue? I'm unfamiliar with the codebase.

[TobiGr]

This is a visual bug only, so most likely related to the corresponding PlayQueueAdapter. The items inside the PlayQueue are ordered correctly. The interesting thing is that it only happens with the background player for me:

Video Player	Background Player
Video Player.webm

Notice that the items are swapped when opening the fragment. Maybe something is not cleared correctly.

In PlayQueueAdapter, onNext() seems to be called again when opening the View.

[TobiGr]

The underlying issue is that the PlayQueue uses a BehaviorSubject<PlayQueueEvent>. It emits the last event after onSubscribe(). @Stypox Is there a reason, why a BehaviorSubject was used and not a PublishSubject? This uses the expected flow.