WebAPI/SpeakerManager
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< WebAPI
Contents
Speaker Control API
General Use Cases: Allow application can control acoustic sound output through speaker.
Proposed API
[Constructor()] interface MozSpeakerManager : EventTarget { /* query the speaker status */ readonly attribute boolean speakerforced; /* force the device's sound go through speaker */ attribute boolean forcespeaker; /* this event will be fired when force speaker status change */ attribute EventHandler onspeakerforcedchange; };
Example:Turn on speaker
var sm = new MozSpeakerManager(); // fired anytime when device's speaker status changed sm.onspeakerforcedchange = function() { bool enabled = sm.speakerforced; // Refresh UI return; } if (sm.speakerforced) { // device's speaker is on } else { sm.forcespeaker = true; }
Use cases
- Listen to FM Radio and want to output sounds to speaker audio path.
- Dialer can force output sound from earpiece to speaker
Behavior
- speakerforced reflects phone status. I.e. if the speaker is currently forced on then this always returns true, no matter which app forced the speaker to be on.
- onspeakerforcedchange fires anytime speakerforced changes.
- forcespeaker=true means that this app attempts to force the speaker to be on. This is only honored if the app is currently in the foreground. So if a foreground app calls forcespeaker=true that means that 'speakerforced' in all applications switches to true, and any audio from any application will go to the speaker.
- If a background app calls forcespeaker=true that doesn't change anything. 'speakerforced' remains false everywhere.
- If an app that has called forcespeaker=true, but no audio is currently playing in the app itself, is switched to the background we switch 'speakerforced' to false in all apps.
- If an app that has called forcespeaker=true, and audio is currently playing in the app itself, is switched to the background 'speakerforced' remains true in all apps. If/when the app stops playing audio, 'speakerforced' switches to false in all apps.
- If an app that has called forcespeaker=true is switched from the background to the foreground 'speakerforced' switches to true in all apps. I.e. the app doesn't have to call forcespeaker=true again when it comes into foreground.
Permissions Table
Type | Use Cases | Authorization Model | Notes & Other Controls |
---|---|---|---|
Web Content | None | No access | |
Installed Web Apps | None | No access | |
Privileged Web Apps | General use cases | Implicit | |
Certified Web Apps | General use cases | Implicit |