I am trying to get a sound file to play faster in order to keep up with the text reveal in the following code. The sound works (in Firefox, anyway), but it only seems to play one instance of the file at a time.
I'd like to have each letter pop onto the screen accompanied by the popping sound. Right now the popping sound is sort of random, and not timed to play with each letter.
I'm wondering if I need to have multiple instances of the sound object, and how to do that.
I already shortened the sound file as much as I could, and the length of the file is shorter than the setTimeout interval I'm using. It just won't overlap multiple copies of the same sound file, for some very good reason that I don't know, I'm sure.
Here is the whole code:
(I tried to JSFiddle it, but couldn't get that to work (I'll save that question for a later date))
<html>
<head>
<style>
#display {
color: white;
font-size: 150%;
padding: 2em 5em;
min-height: 600px;
max-width: 600px;
margin-left: auto;
margin-right: auto;
}
body {
background-color: black;
padding: 0;
margin:0;
}
</style>
<script>
var text = "Test String... 1, 2, 3; Everything seems to be working, but the sound is lagging.";
var charDelay = 40; // Sets the delay time for the character loop
function loadText() {
var i = 0; // Character counter
var myPud = new Audio("http://southernsolutions.us/audio/pud03.ogg");
var displayBox = document.getElementById("display");
displayBox.innerHTML = "<p>";
textLoop();
function textLoop() {
if (i == text.length){ // This condition terminates the loop
displayBox.innerHTML += "</p>";
return;
} else if (i < text.length) { // This condition appends the next character
displayBox.innerHTML += text[i];
i++;
myPud.play();
setTimeout(function(){return textLoop()}, charDelay);
}
}
}
window.onload = function(){loadText()};
</script>
</head>
<body>
<div id="display"></div>
</body>
</html>
I'd suggest that you make the sound loop a little longer, say 1 second. Then, control the sound playing through event listeners so that once the text has finished, you stop the sound playing.
Trying to do it as you're doing it now, you could speed up the sound with how its playing in the audio file. This should give better results. That, or slow down the time out.
Below is some code that I've tested which would let you do it through event listeners. The results are similar to what you had, but if you took your audio file, increased it to 1 second and changed it up to have 24 clicks in there, you'd get the exact effect you were looking for.
Edit: I've also updated the below to take into account the comments.
<script>
var text = "Test String... 1, 2, 3; Everything seems to be working, but the sound is lagging.";
var charDelay = 40; // Sets the delay time for the character loop
function loadText() {
var i = 0; // Character counter
var myPud = new Audio("http://southernsolutions.us/audio/pud03.ogg");
var displayBox = document.getElementById("display");
// Toggle for whether to loop
var stillPlay = true;
displayBox.innerHTML = "<p>";
// Listen for when it ends
myPud.addEventListener("ended", onAudioComplete);
// Begin playing
myPud.play();
// Start the loop
textLoop();
function textLoop() {
if (i == text.length){ // This condition terminates the loop
displayBox.innerHTML += "</p>";
// If we're at the end, we want to stop playing
stillPlay = false;
// Rather than duplicate code, jump straight into the complete function
onAudioComplete(null);
return;
} else if (i < text.length) { // This condition appends the next character
displayBox.innerHTML += text[i];
i++;
// Direct reference to the function to avoid more anony. functions
setTimeout(textLoop, charDelay);
}
}
// On audio complete
function onAudioComplete(e){
// Can we still play? If so, play
if(stillPlay){
myPud.play();
} else {
// Otherwise, remove the event listener, stop and null out.
myPud.removeEventListener("ended", onAudioComplete);
myPud.stop();
myPud = null;
}
}
}
window.onload = loadText;
</script>
Related
I'm writing a choose your own adventure program where If a specific option is chosen (example to wait) the user gets a random number between 1-10 to do push ups(the push-ups would be the user clicking on the prompt "ok" button however many times the random number is equal to) here's my code so far but I keep getting errors. I'm a complete noob so go easy on me.
var count = Math.floor((Math.random() * 10) + 1);
var setsOf10 = false;
function pushUps() {
alert("Nice! Lets see you crank out " + pushUps + "!");
}
if (setsOf10 == pushUp) {
alert("Nice! Lets see you crank out " + pushUp + "!");
setsOf10 = true;
}
for (var i=0; i<count; i++){
pushUps();
}
else {
alert("Really, thats it? Try again");
}
while ( setsOf10 == false);
}
After playing with this some more I can tell i'm close but still don't have it. and again, I'M NOT ASKING YOU TO SOLVE THIS FOR ME JUST NEED POINTERS AS TO WHAT IM DOING WRONG OR MISSING. Here's what I have, Its giving me my random number I just need it to allow me to click the "ok" button however many times the random number has assigned me.
var pushUpSets = Math.floor((Math.random() * 10) + 1);
function pushUps(){
alert(pushUpSets);
if (pushUpSets < 3){
var weak = "Thats it? Weak sauce!";
alert(weak);
}
else{
alert("Sweet lets get some reps in!");
}
for (i=0; i>3; i++){
pushUps(pushUpSets);
}
}
Here, the make a choice button is just dummy to allow us to go to do push ups. Each click decrements our count.
// This is important, we use this event to wait and let the HTML (DOM) load
// before we go ahead and code.
document.addEventListener('DOMContentLoaded', () => {
document.querySelector('#choice').addEventListener('click', makeChoice);
});
function makeChoice() {
// Call a method to set random pushups and setup the click event
setUpPushUp();
// Here we change the display style of the push up section so that it shows to the player.
document.querySelector('.activity').style.display = 'block';
}
// The pushups variable is declared at the document level
// This way our setUpPushUp and doPushUp functions have easy access.
let pushUps = 0;
function setUpPushUp() {
// Create a random number of pushups, in sets of 10.
// We add an extra 1 so we can call the doPushUp method to initialize.
pushUps = (Math.floor((Math.random() * 10)+1)*10)+1 ;
// Add a click event to the push up button and call our doPushUp method on each click.
document.querySelector('#push').addEventListener('click', doPushUp);
// This is just an init call, it will use the extra 1 we added and place test in our P tag.
doPushUp();
}
function doPushUp() {
// Get a reference to our output element, we will put text to player here.
let result = document.querySelector('p');
// They have clicked, so remove a push up.
pushUps--;
// See if the player has done all the required push ups (i.e. pushUps is 0 or less.)
if (pushUps > 0) {
result.innerText = `You need to crank out ${pushUps} pushUps`;
} else {
result.innerText = 'Nice work!';
}
}
.activity {
display: none;
}
<button id="choice">Make a choice !</button>
<div class="activity">
<p></p>
<button id="push">Push</button>
</div>
I need to emulate what an old manual typewriter does when printing what is being typed on a web page. I want to develop JavaScript functions to pass it a string, and it would print out each character with a delay, and the sound file synced with each letter.
I'm new to JavaScript. What is the preferred method to do this? Should I be looking at jQuery for this? Or is this something simple to do?
I've seen problems with sound files being triggered like this on some web browsers, is there an audio file format which is best for this sort of thing?
I've found this, but the problem is, it doesn't work on all web browsers:
https://rawgit.com/mehaase/js-typewriter/master/example3-typewriter/index.html
You can try something like this:
// The delay between each keystroke
var delay = 300;
// The typewriter sound file url
var clickURL = "https://cdn.rawgit.com/halimb/res/6ffa798d/typewriter.wav";
// Get a reference to the container div
var container = document.getElementById("container");
var sampleString = "Hello world!";
//get a reference to the start button and typewrite onclick
var start = document.getElementById("btn");
start.onclick = function() { typewrite( sampleString ); };
function typewrite( str ) {
var i = 0;
container.innerHTML = "";
type();
function type() {
var click = new Audio( clickURL );
// This is triggered when the browser has enough of the file to play through
click.oncanplaythrough = function() {
click.play();
// Add the character to the container div
container.innerHTML += str[i];
i++;
if(i < str.length) {
window.setTimeout(type, delay);
}
}
}
}
* {
font-family: Courier;
font-size: 32px;
}
.btn {
display: inline-block;
border: 1px solid black;
border-radius: 5px;
padding: 10px;
cursor: pointer;
margin: 10px;
}
<div class="btn" id="btn">Start</div>
<div id="container"></div>
Update: on Safari. It seems the audio has to be triggered by a user event (e.g: onclick..), so I added a button, and made the typewriter start onclick.
The downside is that there's no way to pre-load the audio file, Safari make a server request and downloads the audio each time it is played. the only (dirty) way I could think of to overcome this is to provide a data URI instead of the audioURL.. you can try that if the playback speed really matters (this can be helpful: https://www.ibm.com/developerworks/library/wa-ioshtml5/)
I'm trying to create a simple slideshow effect. I have 10 images, and I've created a basic HTML page with 2 buttons to go to the right or left image. On clicking the button, the images change.
Now, I'm trying to add a basic fade functionality to the changing image. But the fade effect isn't getting displayed. When I put alerts, I notice that the fade is taking place, but without the alerts it is too fast to be visible. Also, it is happening on the previous image, instead of the next one.
<html>
<head>
<style>
.main {
text-align: center;
}
.centered {
display: inline-block;
}
#image {
border: solid 2px;
width: 500px;
height: 500px;
}
#number {
font-size: 30px;
}
</style>
<script>
function goLeft() {
var image = document.getElementById("image");
var pos = document.getElementById("number");
if(Number(pos.innerHTML)==1) {
image.src = "Images\\10.jpg"
pos.innerHTML = 10;
} else {
image.src = "Images\\" + (Number(pos.innerHTML)-1).toString() + ".jpg"
pos.innerHTML = (Number(pos.innerHTML)-1).toString();
}
for (var i=0; i<25; i++) {
setTimeout(changeOpacity(image, i), 1000);
}
}
function changeOpacity(image, i) {
alert(parseFloat(i*4/100).toString());
image.style.opacity = (parseFloat(i*4/100).toString()).toString();
}
function goRight() {
var image = document.getElementById("image");
var pos = document.getElementById("number");
if(Number(pos.innerHTML)==10) {
image.src = "Images\\1.jpg"
pos.innerHTML = 1;
} else {
image.src = "Images\\" + (Number(pos.innerHTML)+1).toString() + ".jpg"
pos.innerHTML = (Number(pos.innerHTML)+1).toString();
}
for (var i=0; i<25; i++) {
setTimeout(changeOpacity(image, i), 1000);
}
}
</script>
</head>
<body>
<div class="main">
<div class="centered">
<img id="image" src="Images\1.jpg">
</div>
</div>
<div class="main">
<div class="centered">
<span id="number">1</span>
</div>
</div>
<div class="main">
<div class="centered">
<button onclick="goLeft()" style="margin-right:50px;">Go Left</button>
<button onclick="goRight()" style="margin-left:50px;">Go Right</button>
</div>
</div>
</body>
The problem is this block of code that is in your goLeft method, and goRight method:
for (var i=0; i<25; i++) {
setTimeout(changeOpacity(image, i), 1000);
}
You are creating 25 timers that, and each timer will execute approximately 1 second later.
Creating animations is best left to the CSS.
In your CSS add:
#image {
transition: opacity 0.5s ease;
}
And then in your JavaScript, simply: image.style.opacity = 1.0;
When the opacity changes, CSS will automatically transition the opacity length at the speed defined in the css, e.g 0.5s. Feel free to experiment.
I also added a jsfiddle here: http://jsfiddle.net/dya7L8wq/
You misunderstood setTimeout and the for loop.
Norman's answer provides a good solution with CSS, but he doesn't talk too much about why your code is not working. So I'd like to explain.
for (var i=0; i<25; i++) {
setTimeout(changeOpacity(image, i), 1000);
}
You assumption is:
invoke changeOpacity(image, 0) after 1 second
invoke changeOpacity(image, 1) 1 second after step 1
invoke changeOpacity(image, 2) 1 second after step 2
invoke changeOpacity(image, 3) 1 second after step 3
....
And the last step is invoking changeOpacity(image, 24) 1 second after previous step.
What actually happens is:
The loop is finished almost immediately!
In each iteration, setTimeout queues an asynchronous function invocation, and it's done! That says, it will return right away, rather than wait until changeOpacity returns.
And then, after about 1 second, changeOpacity fires 25 times almost at the same time, because you queued it 25 times in the for loop.
Another problem here is: in changeOpacity invocations, passed-in parameter i are not 1, 2, 3...., they all have the same value that causes for loop to exit (1 second ago) - 25, because JS doesn't have a block scope prior to ES6 (in ES6 we have keyword let for it).
In a pure JS solution, to ensure the time sequence we'd usually queue next invocation at the end of every step:
function changeOpacity() {
// do something here
// before the function returns, set up a future invocation
setTimeout(changeOpacity, 1000)
}
Here's an example to print a list of numbers from 1 to 5:
var go = document.getElementById('go')
var op = document.getElementById('output')
var i = 0
function printNum() {
var p = document.createElement('p')
p.innerHTML = ++i
op.appendChild(p)
// next step
if(i < 5) {
setTimeout(printNum, 500)
}
}
go.onclick = printNum
<button id="go">GO</button>
<div id="output"></div>
Why use pure JavaScript?
Use jQuery.
It has a pretty neat fadeTo() function and a useful fadeIn() function.
Might wanna use that ;)
I have a site that has an image gallery that changes images every few seconds using JavaScript; however, I want to know how to STOP the images from changing when a user clicks on one of the images.
So far, the images are rotating as planned, but I can't seem to get the "onClick" scripting to STOP the rotation when the user clicks on an image. I don't need to have an alert popup or need it to do anything, I just need it to STOP the image rotation when someone clicks on one of the pictures.
Here's the HTML code I have:
else (getValue=='STOP')
{
alert("STOPPED");
}
That won't do what you probably want it to do. It should be:
else if (getValue=='STOP')
{
alert("STOPPED");
}
First of all, you missed out on the keyword "IF" in one of the lines of your code.
However, the way to create a terminable repetitive action is to setInterval and then use clearInterval to terminate the repetition.
semaphore = setInterval(somefunction, someinterval);
clearInterval(semaphore);
Example (I wrote this off-the-cuff, so there might be some errors, but you shd get the idea):
<img src="./images/image1.jpg" id="imageGallery" name="imageGallery"
onclick="chooseImg(this)" />
<script>
var turn = setInterval(function(){imgTurn()},5000);
var images = function2CreateImgArray();
var imageN = 0;
function chooseImg(img){
clearInterval(turn);
function2DisplayImg(imageN); // or do whatever
}
function imgTurn(){
if (imageN++ >= images.length) imageN = 0;
function2DisplayImg(imageN++);
}
</script>
You could replace the setInterval with setTimeout.
var turn = setTimeout(function(){imgTurn()},5000);
But then you need to use clearTimeout to stop it:
clearTimeout(turn);
But if you use setTimeout, you would need to setTimeout for the next image display, so you would not even need to clearTimeout to stop the rotation.
<img src="./images/image1.jpg" id="imageGallery" name="imageGallery"
onclick="chooseImg(this)" />
<script>
setTimeout(function(){imgTurn()},5000);
var images = function2CreateImgArray();
var imageN = 0;
var turn = 1;
function chooseImg(img){
turn = 0;
function2DisplayImg(imageN); // or do whatever
}
function imgTurn(){
if (turn==0) return;
if (imageN++ >= images.length) imageN = 0;
function2DisplayImg(imageN++);
}
</script>
I`m having a troubble with a simple thing.
I have an div, when clicked, an amination start (an infinite loop of images changing, simulating an animated gif).
But, when i click on the other div, the first one need to stop, and start just the other animation, and this goes on to every animation (will be 8 on total).
Here is the code for just one image loop:
var t1;
var t2;
var anim1 = new Array ('img/testes2/anim1_1.png','img/testes2/anim1_2.png');
var anim2 = new Array ('img/testes2/anim2_1.png','img/testes2/anim2_2.png');
var index = 1;
var verifica1 = 0;
var verifica2 = 0;
function rotateImage1(){
$('#imagemPrinc').fadeOut(0, function(){
$(this).attr('src', anim1[index]);
$(this).fadeIn(0, function(){
if (index == anim1.length-1){
index = 0;
}
else{
index++;
}
});
});
return false;
}
function stopTimer1(){
if(verifica1 = 1){
clearInterval(t2);
}
}
function muda1(){
if (verifica1 = 1){
//stopTimer2();
//$('#bgImagem').css({'background-image':'url(img/testes2/anim1_1.png)'});
t1 = setInterval(rotateImage1,500);
}
}
The same function for the second animation.
The verifica var, and the stopTimer function, i tried to make one stop, and just the other plays, but doesn't seems to be working. That's why it's commented on the code.
It will be easier to look the code running, so thats it ---HERE---
The clickable divs are those two Red Squares.
Someone can help me please!?
Thanks!
clearTimeout takes as argument the timer id returned by the setInterval function (here it's t1).
Instead of using fadeOut and fadeIn with a duration of 0, you should simply use hide and show.
As an aside, you can simplify this block :
if (index == anim1.length-1){
index = 0;
}
else{
index++;
}
in
index = [(index+1)%anim1.length];
And this is very wrong :
if(verifica1 = 1){
This is not a test : it always change verifica1 and is always true. You probably want ==.
Is there a point in your code where you (voluntarily) set verifica1 ?