Wrong currentWindowIndex onPlayerError

[Khang-NT]

Issue description & Reproduction steps

When using ConcatenatingMediaSource to play a playlist of media, let say I'm playing at position i, and position i + 1 failed to load. Then within onPlayerError callback, I expectcurrentWindowIndex should return i + 1 but actually it return i. Is it intended behavior?

Version of ExoPlayer being used

2.9.3

[tonihei]

Is it intended behavior?

That's not exactly intended behaviour and for load errors specifically we should report the loading source window index. Note that the non-fatal onLoadError callbacks already have the correct window index. However, the fatal onPlayerError always gets assigned to the currently playing window index. As we can't switch to the next window if there is a load error, you still see the previous window index in onPlayerError as the "playing" one.

[tonihei]

Probably wasn't clear from my previous comment:

• player.getCurrentWindowIndex will still return the previous window index in all cases because we can't switch to the next item we don't get any samples.
• EventTime.windowIndex in the AnalyticsListener callbacks will contain the correct association from error to window.

[Khang-NT]

This behavior will lead to:

• PlayerView display last video frame or thumbnail of item i while showing error message of item i + 1. When shuffle is enabled, it will confuse user because next item is unknown random position.
• I can't call skip() within onPlayerError. Because it actually set the window index to i + 1 where the media item can't play. Then somehow I need to call skip "twice".

[tonihei]

Fixing it in the way you describe would require some changes in how we progress internally through the playlist. Right now, we don't change the playing source to the next item until the next source is fully prepared. I agree that this not ideal, but it requires moving around some code in our core player. And a lot of care not to break things in the process. :)

I'll re-open as an enhancement, but also mark it as low priority for now for the reason given above.