This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The onvoiceschanged
property of the SpeechSynthesis
interface represents an event handler that will run when the list of SpeechSynthesisVoice
objects that would be returned by the SpeechSynthesis.getVoices()
method has changed (when the voiceschanged
event fires.)
This may occur when speech synthesis is being done on the server-side and the voices list is being determined asynchronously, or when client-side voices are installed/uninstalled while a speech synthesis application is running.
Syntax
speechSynthesisInstance.onvoiceschanged = function() { ... };
Examples
This could be used to populate a list of voices that the user can choose between when the event fires (see our Speak easy synthesis demo.) Note that Firefox doesn't support it at present, and will just return a list of voices when SpeechSynthesis.getVoices()
is fired. With Chrome however, you have to wait for the event to fire before populating the list, hence the bottom if statement seen below.
var voices = []; function populateVoiceList() { voices = synth.getVoices(); for(i = 0; i < voices.length ; i++) { var option = document.createElement('option'); option.textContent = voices[i].name + ' (' + voices[i].lang + ')'; if(voices[i].default) { option.textContent += ' -- DEFAULT'; } option.setAttribute('data-lang', voices[i].lang); option.setAttribute('data-name', voices[i].name); voiceSelect.appendChild(option); } } populateVoiceList(); if (speechSynthesis.onvoiceschanged !== undefined) { speechSynthesis.onvoiceschanged = populateVoiceList; }
Specifications
Specification | Status | Comment |
---|---|---|
Web Speech API The definition of 'onvoiceschanged' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | 33 | (Yes) | No support | No support | No support | No support |
Feature | Android | Chrome | Edge | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | No support | No support | No support | No support | No support |