| // Copyright 2012 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // Custom binding for the tts API. |
| |
| var idGenerator = requireNative('id_generator'); |
| var lazyBG = requireNative('lazy_background_page'); |
| |
| apiBridge.registerCustomHook(function(api) { |
| var apiFunctions = api.apiFunctions; |
| var tts = api.compiledApi; |
| var handlers = {}; |
| |
| function ttsEventListener(event) { |
| var eventHandler = handlers[event.srcId]; |
| if (eventHandler) { |
| eventHandler({ |
| type: event.type, |
| charIndex: event.charIndex, |
| length: event.length, |
| errorMessage: event.errorMessage |
| }); |
| if (event.isFinalEvent) { |
| delete handlers[event.srcId]; |
| // Balanced in 'speak' handler. |
| lazyBG.DecrementKeepaliveCount(); |
| } |
| } |
| } |
| |
| // This file will get run if an extension needs the ttsEngine permission, but |
| // it doesn't necessarily have the tts permission. If it doesn't, trying to |
| // add a listener to chrome.tts.onEvent will fail. |
| // See http://crbug.com/122474. |
| try { |
| tts.onEvent.addListener(ttsEventListener); |
| } catch (e) {} |
| |
| apiFunctions.setHandleRequest( |
| 'speak', function(utterance, options, callback) { |
| if (options && options.onEvent) { |
| var id = idGenerator.GetNextId(); |
| options.srcId = id; |
| handlers[id] = options.onEvent; |
| // Keep the page alive until the event finishes. |
| // Balanced in eventHandler. |
| lazyBG.IncrementKeepaliveCount(); |
| } |
| bindingUtil.sendRequest( |
| 'tts.speak', [utterance, options, callback], undefined); |
| }); |
| }); |