Media Session: add support for platform-specific interruption providers

• Component: Media
• Status: RESOLVED FIXED

[Matt Rajca]

Interruption providers will notify media sessions of start/end-of-interruption events.

[Matt Rajca]

Created attachment 256916 [details]
Patch

[Radar WebKit Bug Importer]

<rdar://problem/21858652>

[Eric Carlson]

Comment on attachment 256916 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=256916&action=review

> Source/WebCore/ChangeLog:9
> +        * platform/audio/MediaSessionInterruptionProvider.cpp: Added base class to be used by MediaSessionManager to

Nit: This isn't audio-specific, so why don't you put it into a new "platform/mediasession" directory?

> Source/WebCore/platform/audio/MediaSessionInterruptionProvider.cpp:37
> +MediaSessionInterruptionProvider::MediaSessionInterruptionProvider(MediaSessionInterruptionProviderClient& client)
> +    : m_client(&client)
> +{
> +    beginListeningForInterruptions();
> +}

Will there ever be more than one interruption provider? If so, what is the lifetime of an object - who creates it?

If there will only ever be one, you need a static accessor method and you need a way to add/remove clients.

[Matt Rajca]

(In reply to comment #3)
> Comment on attachment 256916 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=256916&action=review
> 
> > Source/WebCore/ChangeLog:9
> > +        * platform/audio/MediaSessionInterruptionProvider.cpp: Added base class to be used by MediaSessionManager to
> 
> Nit: This isn't audio-specific, so why don't you put it into a new
> "platform/mediasession" directory?

Will do.

> 
> > Source/WebCore/platform/audio/MediaSessionInterruptionProvider.cpp:37
> > +MediaSessionInterruptionProvider::MediaSessionInterruptionProvider(MediaSessionInterruptionProviderClient& client)
> > +    : m_client(&client)
> > +{
> > +    beginListeningForInterruptions();
> > +}
> 
> Will there ever be more than one interruption provider? If so, what is the
> lifetime of an object - who creates it?

The interruption provider will only be used by the MediaSessionManager singleton (there will only be one client).

> 
> If there will only ever be one, you need a static accessor method and you
> need a way to add/remove clients.

[Eric Carlson]

Comment on attachment 256916 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=256916&action=review

> Source/WebCore/platform/audio/MediaSessionInterruptionProvider.h:57
> +    // To be overriden by subclasses.
> +    virtual void beginListeningForInterruptions();
> +    virtual void stopListeningForInterruptions();

If these must be overridden, why not make the pure-virtual?

> Source/WebCore/platform/audio/mac/MediaSessionInterruptionProviderMac.h:37
> +    using MediaSessionInterruptionProvider::MediaSessionInterruptionProvider;

Is this necessary?

[Matt Rajca]

(In reply to comment #5)
> Comment on attachment 256916 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=256916&action=review
> 
> > Source/WebCore/platform/audio/MediaSessionInterruptionProvider.h:57
> > +    // To be overriden by subclasses.
> > +    virtual void beginListeningForInterruptions();
> > +    virtual void stopListeningForInterruptions();
> 
> If these must be overridden, why not make the pure-virtual?

These methods are called from the base class's constructor and destructor so they cannot be pure virtual.

> 
> > Source/WebCore/platform/audio/mac/MediaSessionInterruptionProviderMac.h:37
> > +    using MediaSessionInterruptionProvider::MediaSessionInterruptionProvider;
> 
> Is this necessary?

Yes, constructors aren't inherited.

[Matt Rajca]

Committed r186917: <http://trac.webkit.org/changeset/186917>