176747 - nsISound::Play(aSoundURL) not working except in one weird case

Status: RESOLVED INVALID

(Core :: XUL, defect)

Description

[Aaron Leventhal]

I can't add a custom .wav file to typeaheadfind, because
nsISound::Play(aSoundURL) is not working.

The strange thing is, I can get it to work if I use the debugger, trace into
this one line of code and step over it.
  BOOL PlaySound(const char *aSoundFile,HMODULE aModule,DWORD aOptions) {
    return (mPlay) ? mPlay(aSoundFile, aModule, aOptions) : FALSE;
  }

If I just let it run normally the sound won't play, either in the debug or
release builds.

Comment 1

[Aaron Leventhal]

This stinks, I want my custom sound. Someone gimme a clue to what's going on
here? Something to do with threads?

Comment 2

[Aaron Leventhal]

Okay, I figured out what was going wrong. I was using:
nsCOMPtr<nsISound> soundInterface = do_CreateInstance("@mozilla.org/sound;1");

The problem with this is that nsISound::Play() uses OnStreamComplete() to play
the sound, which might not be called before the com pointer goes out of scope,
and thus the destructor gets called before the sound has a chance to get played.

Comment 3

[Aaron Leventhal]

The caller just needs to make sure their COMPtr doesn't go out of scope too soon.