Getting 'sending message to a Handler on a dead thread' (dev branch)

[dnutcracker]

When performing the following call from the UI main thread:
exoPlayer.blockingSendMessage(videoRenderer, MediaCodecVideoTrackRenderer.MSG_SET_SURFACE, null);

I randomly get the following exception:

05-03 13:41:39.468  23310-25973/me.samba.app W/MessageQueue﹕ Handler (com.google.android.exoplayer.upstream.Loader$LoadTask) {44fe3a10} sending message to a Handler on a dead thread
    java.lang.RuntimeException: Handler (com.google.android.exoplayer.upstream.Loader$LoadTask) {44fe3a10} sending message to a Handler on a dead thread
            at android.os.MessageQueue.enqueueMessage(MessageQueue.java:320)
            at android.os.Handler.enqueueMessage(Handler.java:626)
            at android.os.Handler.sendMessageAtTime(Handler.java:595)
            at android.os.Handler.sendMessageDelayed(Handler.java:566)
            at android.os.Handler.sendEmptyMessageDelayed(Handler.java:530)
            at android.os.Handler.sendEmptyMessage(Handler.java:515)
            at com.google.android.exoplayer.upstream.Loader$LoadTask.run(Loader.java:249)
            at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:422)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:841)

What am I doing wrong?

[ojw28]

It's only a warning in the logs, right? What's actually happening here is that one of ExoPlayer's loading threads is notifying the playback thread after the playback thread has exited (because you called release() on the player). This is working as intended, and the warning can be safely ignored.

It's slightly unfortunate that the platform chooses to print this warning at all, since there are cases such as this one where the behavior is intentional and expected.

[dnutcracker]

Yep - it is a little bit annoying.

Can the release() ask the loading threads to stop?
Can the loading threads check if release() was called before trying to notify the playback thread?

[ojw28]

We can probably suppress it in most cases; I'll take a look at doing that. It's not possible to suppress it in 100% of cases though (doing this would require the playback thread to potentially block on network reads, which violates the threading model and may lead to application ANRs).

[dnutcracker]

Great. Thanks.

On Tue, May 5, 2015 at 11:41 AM, ojw28 notifications@github.com wrote:

We can probably suppress it in most cases; I'll take a look at doing that.
It's not possible to suppress it in 100% of cases though (doing this would
require the playback thread to potentially block on network reads, which
violates the threading model and may lead to application ANRs).

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Reply to this email directly or view it on GitHub
#426 (comment).

[chrisjenx]

Wouldn't getLooper().getThread().isAlive() make more sense?

[ojw28]

I don't think any of these solutions are completely ideal. I'm inclined to do nothing, given there's no actual adverse affects to the user or application. The best long term solution would be a platform change to allow these kind of warnings to be turned off. I'll follow up internally about that (obviously it would only help in new platform releases).

[chrisjenx]

Yeah, I've seen them before, not sure why they are exposed to the user.

Agreed, was just my two cents.

On Thu, 20 Aug 2015 12:50 ojw28 notifications@github.com wrote:

I don't think any of these solutions are completely ideal. I'm inclined to
do nothing, given there's no actual adverse affects to the user or
application. The best long term solution would be a platform change to
allow these kind of warnings to be turned off. I'll follow up internally
about that (obviously it would only help in new platform releases).

—
Reply to this email directly or view it on GitHub
#426 (comment).

[issamux]

Any solution for this warning ?
Player show a warning icon (File not found) even if the link is ok .??)

08-26 13:07:45.977: W/MessageQueue(3405): Handler (android.os.Handler) {422005a8} sending message to a Handler on a dead thread

[chrisjenx]

@issamux sounds like two different issues, The Handler issue is safe to ignore as stated. Its just a warning, they shouldn't really be exposed to the user.

[issamux]

@chrisjenx yes, u're right ,bad link issue solved... but the handler warning message still loged in android log messages
thanks