I'm looking for code examples for the Gamepad API for Google Dart.
I've tried relying on the API doc directly and attempted to write out an instance for it.
//Gamepad Example:
Gamepad g = new Gamepad();
g.id.toString(); // This doesn't seem to return anything...
If anyone has any code examples for this that would be fantastic!
I tried this and it worked for me :
import "dart:html";
main(){
window.animationFrame.then(runAnimation);
}
runAnimation(timestamp){
var gamepads = window.navigator.getGamepads();
for (var pad in gamepads)
{
if(pad != null){
querySelector("#buttons").setInnerHtml("${pad.buttons.join(" ")}</br>${pad.axes.join(" ")}");
}
}
window.requestAnimationFrame(runAnimation);
}
I don't have a gamepad to try but
Gamepad g = new Gamepad();
doesn't work because Gamepade has no public constructor.
Try
var gp = window.navigator.getGamepads();
//or
// haven't tried because I don't know how to provoke this event without a gamepad
window.on['gamepadconnected'].listen((e) {
var gamepad = e.gamepad;
});
instead.
I get an empty list so I can't examine more.
see also:
- https://developer.mozilla.org/en-US/docs/Web/Guide/API/Gamepad
- https://dvcs.w3.org/hg/gamepad/raw-file/default/gamepad.html
Following HTML shows empty array in console on first click:
<!DOCTYPE html>
<html>
<head>
<script>
function test(){
console.log(window.speechSynthesis.getVoices())
}
</script>
</head>
<body>
Test
</body>
</html>
In second click you will get the expected list.
If you add onload event to call this function (<body onload="test()">), then you can get correct result on first click. Note that the first call on onload still doesn't work properly. It returns empty on page load but works afterward.
Questions:
Since it might be a bug in beta version, I gave up on "Why" questions.
Now, the question is if you want to access window.speechSynthesis on page load:
What is the best hack for this issue?
How can you make sure it will load speechSynthesis, on page load?
Background and tests:
I was testing the new features in Web Speech API, then I got to this problem in my code:
<script type="text/javascript">
$(document).ready(function(){
// Browser support messages. (You might need Chrome 33.0 Beta)
if (!('speechSynthesis' in window)) {
alert("You don't have speechSynthesis");
}
var voices = window.speechSynthesis.getVoices();
console.log(voices) // []
$("#test").on('click', function(){
var voices = window.speechSynthesis.getVoices();
console.log(voices); // [SpeechSynthesisVoice, ...]
});
});
</script>
<a id="test" href="#">click here if 'ready()' didn't work</a>
My question was: why does window.speechSynthesis.getVoices() return empty array, after page is loaded and onready function is triggered? As you can see if you click on the link, same function returns an array of available voices of Chrome by onclick triger?
It seems Chrome loads window.speechSynthesis after the page load!
The problem is not in ready event. If I remove the line var voice=... from ready function, for first click it shows empty list in console. But the second click works fine.
It seems window.speechSynthesis needs more time to load after first call. You need to call it twice! But also, you need to wait and let it load before second call on window.speechSynthesis. For example, following code shows two empty arrays in console if you run it for first time:
// First speechSynthesis call
var voices = window.speechSynthesis.getVoices();
console.log(voices);
// Second speechSynthesis call
voices = window.speechSynthesis.getVoices();
console.log(voices);
According to Web Speech API Errata (E11 2013-10-17), the voice list is loaded async to the page. An onvoiceschanged event is fired when they are loaded.
voiceschanged: Fired when the contents of the SpeechSynthesisVoiceList, that the getVoices method will return, have changed. Examples include: server-side synthesis where the list is determined asynchronously, or when client-side voices are installed/uninstalled.
So, the trick is to set your voice from the callback for that event listener:
// wait on voices to be loaded before fetching list
window.speechSynthesis.onvoiceschanged = function() {
window.speechSynthesis.getVoices();
...
};
You can use a setInterval to wait until the voices are loaded before using them however you need and then clearing the setInterval:
var timer = setInterval(function() {
var voices = speechSynthesis.getVoices();
console.log(voices);
if (voices.length !== 0) {
var msg = new SpeechSynthesisUtterance(/*some string here*/);
msg.voice = voices[/*some number here to choose from array*/];
speechSynthesis.speak(msg);
clearInterval(timer);
}
}, 200);
$("#test").on('click', timer);
After studying the behavior on Google Chrome and Firefox, this is what can get all voices:
Since it involves something asynchronous, it might be best done with a promise:
const allVoicesObtained = new Promise(function(resolve, reject) {
let voices = window.speechSynthesis.getVoices();
if (voices.length !== 0) {
resolve(voices);
} else {
window.speechSynthesis.addEventListener("voiceschanged", function() {
voices = window.speechSynthesis.getVoices();
resolve(voices);
});
}
});
allVoicesObtained.then(voices => console.log("All voices:", voices));
Note:
When the event voiceschanged fires, we need to call .getVoices() again. The original array won't be populated with content.
On Google Chrome, we don't have to call getVoices() initially. We only need to listen on the event, and it will then happen. On Firefox, listening is not enough, you have to call getVoices() and then listen on the event voiceschanged, and set the array using getVoices() once you get notified.
Using a promise makes the code more clean. Everything related to getting voices are in this promise code. If you don't use a promise but instead put this code in your speech routine, it is quite messy.
You can write a voiceObtained promise to resolve to a voice you want, and then your function to say something can just do: voiceObtained.then(voice => { }) and inside that handler, call the window.speechSynthesis.speak() to speak something. Or you can even write a promise speechReady("hello world").then(speech => { window.speechSynthesis.speak(speech) }) to say something.
heres the answer
function synthVoice(text) {
const awaitVoices = new Promise(resolve=>
window.speechSynthesis.onvoiceschanged = resolve)
.then(()=> {
const synth = window.speechSynthesis;
var voices = synth.getVoices();
console.log(voices)
const utterance = new SpeechSynthesisUtterance();
utterance.voice = voices[3];
utterance.text = text;
synth.speak(utterance);
});
}
At first i used onvoiceschanged , but it kept firing even after the voices was loaded, so my goal was to avoid onvoiceschanged at all cost.
This is what i came up with. It seems to work so far, will update if it breaks.
loadVoicesWhenAvailable();
function loadVoicesWhenAvailable() {
voices = synth.getVoices();
if (voices.length !== 0) {
console.log("start loading voices");
LoadVoices();
}
else {
setTimeout(function () { loadVoicesWhenAvailable(); }, 10)
}
}
setInterval solution by Salman Oskooi was perfect
Please see https://jsfiddle.net/exrx8e1y/
function myFunction() {
dtlarea=document.getElementById("details");
//dtlarea.style.display="none";
dtltxt="";
var mytimer = setInterval(function() {
var voices = speechSynthesis.getVoices();
//console.log(voices);
if (voices.length !== 0) {
var msg = new SpeechSynthesisUtterance();
msg.rate = document.getElementById("rate").value; // 0.1 to 10
msg.pitch = document.getElementById("pitch").value; //0 to 2
msg.volume = document.getElementById("volume").value; // 0 to 1
msg.text = document.getElementById("sampletext").value;
msg.lang = document.getElementById("lang").value; //'hi-IN';
for(var i=0;i<voices.length;i++){
dtltxt+=voices[i].lang+' '+voices[i].name+'\n';
if(voices[i].lang==msg.lang) {
msg.voice = voices[i]; // Note: some voices don't support altering params
msg.voiceURI = voices[i].voiceURI;
// break;
}
}
msg.onend = function(e) {
console.log('Finished in ' + event.elapsedTime + ' seconds.');
dtlarea.value=dtltxt;
};
speechSynthesis.speak(msg);
clearInterval(mytimer);
}
}, 1000);
}
This works fine on Chrome for MAC, Linux(Ubuntu), Windows and Android
Android has non-standard en_GB wile others have en-GB as language code
Also you will see that same language(lang) has multiple names
On Mac Chrome you get en-GB Daniel besides en-GB Google UK English Female and n-GB Google UK English Male
en-GB Daniel (Mac and iOS)
en-GB Google UK English Female
en-GB Google UK English Male
en_GB English United Kingdom
hi-IN Google हिन्दी
hi-IN Lekha (Mac and iOS)
hi_IN Hindi India
Another way to ensure voices are loaded before you need them is to bind their loading state to a promise, and then dispatch your speech commands from a then:
const awaitVoices = new Promise(done => speechSynthesis.onvoiceschanged = done);
function listVoices() {
awaitVoices.then(()=> {
let voices = speechSynthesis.getVoices();
console.log(voices);
});
}
When you call listVoices, it will either wait for the voices to load first, or dispatch your operation on the next tick.
I used this code to load voices successfully:
<select id="voices"></select>
...
function loadVoices() {
populateVoiceList();
if (speechSynthesis.onvoiceschanged !== undefined) {
speechSynthesis.onvoiceschanged = populateVoiceList;
}
}
function populateVoiceList() {
var allVoices = speechSynthesis.getVoices();
allVoices.forEach(function(voice, index) {
var option = $('<option>').val(index).html(voice.name).prop("selected", voice.default);
$('#voices').append(option);
});
if (allVoices.length > 0 && speechSynthesis.onvoiceschanged !== undefined) {
// unregister event listener (it is fired multiple times)
speechSynthesis.onvoiceschanged = null;
}
}
I found the 'onvoiceschanged' code from this article: https://hacks.mozilla.org/2016/01/firefox-and-the-web-speech-api/
Note: requires JQuery.
Works in Firefox/Safari and Chrome (and in Google Apps Script too - but only in the HTML).
async function speak(txt) {
await initVoices();
const u = new SpeechSynthesisUtterance(txt);
u.voice = speechSynthesis.getVoices()[3];
speechSynthesis.speak(u);
}
function initVoices() {
return new Promise(function (res, rej){
speechSynthesis.getVoices();
if (window.speechSynthesis.onvoiceschanged) {
res();
} else {
window.speechSynthesis.onvoiceschanged = () => res();
}
});
}
While the accepted answer works great but if you're using SPA and not loading full-page, on navigating between links, the voices will not be available.
This will run on a full-page load
window.speechSynthesis.onvoiceschanged
For SPA, it wouldn't run.
You can check if it's undefined, run it, or else, get it from the window object.
An example that works:
let voices = [];
if(window.speechSynthesis.onvoiceschanged == undefined){
window.speechSynthesis.onvoiceschanged = () => {
voices = window.speechSynthesis.getVoices();
}
}else{
voices = window.speechSynthesis.getVoices();
}
// console.log("voices", voices);
I had to do my own research for this to make sure I understood it properly, so just sharing (feel free to edit).
My goal is to:
Get a list of voices available on my device
Populate a select element with those voices (after a particular page loads)
Use easy to understand code
The basic functionality is demonstrated in MDN's official live demo of:
https://github.com/mdn/web-speech-api/tree/master/speak-easy-synthesis
but I wanted to understand it better.
To break the topic down...
SpeechSynthesis
The SpeechSynthesis interface of the Web Speech API is the controller
interface for the speech service; this can be used to retrieve
information about the synthesis voices available on the device, start
and pause speech, and other commands besides.
Source
onvoiceschanged
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.)
Source
Example A
If my application merely has:
var synth = window.speechSynthesis;
console.log(synth);
console.log(synth.onvoiceschanged);
Chrome developer tools console will show:
Example B
If I change the code to:
var synth = window.speechSynthesis;
console.log("BEFORE");
console.log(synth);
console.log(synth.onvoiceschanged);
console.log("AFTER");
var voices = synth.getVoices();
console.log(voices);
console.log(synth);
console.log(synth.onvoiceschanged);
The before and after states are the same, and voices is an empty array.
Solution
Although i'm not confident implementing Promises, the following worked for me:
Defining the function
var synth = window.speechSynthesis;
// declare so that values are accessible globally
var voices = [];
function set_up_speech() {
return new Promise(function(resolve, reject) {
// get the voices
var voices = synth.getVoices();
// get reference to select element
var $select_topic_speaking_voice = $("#select_topic_speaking_voice");
// for each voice, generate select option html and append to select
for (var i = 0; i < voices.length; i++) {
var option = $("<option></option>");
var suffix = "";
// if it is the default voice, add suffix text
if (voices[i].default) {
suffix = " -- DEFAULT";
}
// create the option text
var option_text = voices[i].name + " (" + voices[i].lang + suffix + ")";
// add the option text
option.text(option_text);
// add option attributes
option.attr("data-lang", voices[i].lang);
option.attr("data-name", voices[i].name);
// append option to select element
$select_topic_speaking_voice.append(option);
}
// resolve the voices value
resolve(voices)
});
}
Calling the function
// in your handler, populate the select element
if (page_title === "something") {
set_up_speech()
}
Android Chrome - turn off data saver. It was helpfull for me.(Chrome 71.0.3578.99)
// wait until the voices load
window.speechSynthesis.onvoiceschanged = function() {
window.speechSynthesis.getVoices();
};
let voices = speechSynthesis.getVoices();
let gotVoices = false;
if (voices.length) {
resolve(voices, message);
} else {
speechSynthesis.onvoiceschanged = () => {
if (!gotVoices) {
voices = speechSynthesis.getVoices();
gotVoices = true;
if (voices.length) resolve(voices, message);
}
};
}
function resolve(voices, message) {
var synth = window.speechSynthesis;
let utter = new SpeechSynthesisUtterance();
utter.lang = 'en-US';
utter.voice = voices[65];
utter.text = message;
utter.volume = 100.0;
synth.speak(utter);
}
Works for Edge, Chrome and Safari - doesn't repeat the sentences.
I'm trying to teach myself how to write Chrome extensions and ran into a snag when I realized that my jQuery was breaking because it was getting information from the extension page itself and not the tab's current page like I had expected.
Quick summary, my sample extension will refresh the page every x seconds, look at the contents/DOM, and then do some stuff with it. The first and last parts are fine, but getting the DOM from the page that I'm on has proven very difficult, and the documentation hasn't been terribly helpful for me.
You can see the code that I have so far at these links:
Current manifest
Current js script
Current popup.html
If I want to have the ability to grab the DOM on each cycle of my setInterval call, what more needs to be done? I know that, for example, I'll need to have a content script. But do I also need to specify a background page in my manifest? Where do I need to call the content script within my extension? What's the easiest/best way to have it communicate with my current js file on each reload? Will my content script also be expecting me to use jQuery?
I know that these questions are basic and will seem trivial to me in retrospect, but they've really been a headache trying to explore completely on my own. Thanks in advance.
In order to access the web-pages DOM you'll need to programmatically inject some code into it (using chrome.tabs.executeScript()).
That said, although it is possible to grab the DOM as a string, pass it back to your popup, load it into a new element and look for what ever you want, this is a really bad approach (for various reasons).
The best option (in terms of efficiency and accuracy) is to do the processing in web-page itself and then pass just the results back to the popup. Note that in order to be able to inject code into a web-page, you have to include the corresponding host match pattern in your permissions property in manifest.
What I describe above can be achieved like this:
editorMarket.js
var refresherID = 0;
var currentID = 0;
$(document).ready(function(){
$('.start-button').click(function(){
oldGroupedHTML = null;
oldIndividualHTML = null;
chrome.tabs.query({ active: true }, function(tabs) {
if (tabs.length === 0) {
return;
}
currentID = tabs[0].id;
refresherID = setInterval(function() {
chrome.tabs.reload(currentID, { bypassCache: true }, function() {
chrome.tabs.executeScript(currentID, {
file: 'content.js',
runAt: 'document_idle',
allFrames: false
}, function(results) {
if (chrome.runtime.lastError) {
alert('ERROR:\n' + chrome.runtime.lastError.message);
return;
} else if (results.length === 0) {
alert('ERROR: No results !');
return;
}
var nIndyJobs = results[0].nIndyJobs;
var nGroupJobs = results[0].nGroupJobs;
$('.lt').text('Indy: ' + nIndyJobs + '; '
+ 'Grouped: ' + nGroupJobs);
});
});
}, 5000);
});
});
$('.stop-button').click(function(){
clearInterval(refresherID);
});
});
content.js:
(function() {
function getNumberOfIndividualJobs() {...}
function getNumberOfGroupedJobs() {...}
function comparator(grouped, individual) {
var IndyJobs = getNumberOfIndividualJobs();
var GroupJobs = getNumberOfGroupedJobs();
nIndyJobs = IndyJobs[1];
nGroupJobs = GroupJobs[1];
console.log(GroupJobs);
return {
nIndyJobs: nIndyJobs,
nGroupJobs: nGroupJobs
};
}
var currentGroupedHTML = $(".grouped_jobs").html();
var currentIndividualHTML = $(".individual_jobs").html();
var result = comparator(currentGroupedHTML, currentIndividualHTML);
return result;
})();
I am using google translate on my website. (https://translate.google.com/manager/website/suggestions)
Everything works as I want, but how do I manually (with javascript) restore the original language button ?
The idea is this: I got my pages in my languages, so if a user changes this manually (without google translate) I want to disable the actual translation of google translate.
is this possible ?
I checked the iframe that translates generates, but I didn't find an answer there.
with kind regards
Try using this to restore original state:
function() {
var iframe = document.getElementsByClassName('goog-te-banner-frame')[0];
if(!iframe) return;
var innerDoc = iframe.contentDocument || iframe.contentWindow.document;
var restore_el = innerDoc.getElementsByTagName("button");
for(var i = 0; i < restore_el.length; i++){
if(restore_el[i].id.indexOf("restore") >= 0) {
restore_el[i].click();
var close_el = innerDoc.getElementsByClassName("goog-close-link");
close_el[0].click();
return;
}
}
}
Is there some way to get the tab id's of only the tabs that are part of my extension?
myTabs[i].location.reload()
makes error:
Uncaught TypeError: Cannot call method 'reload' of undefined
but this code:
chrome.tabs.executeScript(myTabs[i].id, {code:"document.location.reload(true);"});
works. But better to use correct method:
chrome.tabs.reload(myTabs[i].id)
This really depends on what you mean by "part of my extension".
If you mean tabs that are displaying a page that is contained within your extension you can do the following;
chrome.tabs.query({}, function (tabs) {
var myTabs = [];
for (var i = 0; i < tabs.length; i++) {
if (tabs[i].url.indexOf(chrome.extension.getURL('')) === 0) {
myTabs.push(tabs[i].id);
}
}
console.log(myTabs);
});
If you want to access the DOM of your tabs instead, it gets even easier;
var myTabs = chrome.extension.getViews({type: 'tab'});
With access to the DOM you can simply iterate of each view (DOMWindow) and refresh each page;
for (var i = 0; i < myTabs.length; i++) {
myTabs[i].location.reload()
}
I've tried to do the same thing and using chrome.tabs.query and chrome.tabs.get didn't work for me. This worked perfectly:
var data = chrome.extension.getViews({'type':'tab'});
$.each(data, function(k,v) {
v.window.location.reload();
});