I need to stop theBox - javascript

Hey guys I need to stop theBox when it moves out of the screeen (500x500)
I dont know how to anyhelp?
<style>
#box { position: absolute; top: 0; left: 0; background-color: green; }
</style>
<script>
onload = function() {
var theBox = document.getElementById("box");
function animate() {
if ("theBox")
theBox.style.left = (theBox.offsetLeft+5)+"px";
theBox.style.top = (theBox.offsetTop+5)+"px";
}
setInterval(animate,100);
}
</script>
</head>
<body>
<div id="box">The box</div>
</body>

Just add a check to see if the next move will take the box up to or over 500. Also, I've added a call to clearInterval() when the box stops, to stop the timer.
onload = function() {
var timer;
var theBox = document.getElementById("box");
function animate() {
if(theBox.offsetLeft+5 < 500 && theBox.offsetTop+5 < 500){
theBox.style.left = (theBox.offsetLeft+5)+"px";
theBox.style.top = (theBox.offsetTop+5)+"px";
} else {
clearInterval(timer);
}
}
timer = setInterval(animate,100);
}

I have added and if statement to check if the height of the page is higher than the offset top of the box:
onload = function() {
var theBox = document.getElementById("box");
function animate() {
if ("theBox")
if(window.innerHeight > (theBox.offsetTop+25)){
console.log(theBox.offsetTop+5)
theBox.style.left = (theBox.offsetLeft+5)+"px";
theBox.style.top = (theBox.offsetTop+5)+"px";
}
}
setInterval(animate,100);
}
Code Pen

Related

Getting setTimeout() to work with loading a page

I am trying to move an element in a page after the page loads. I'm trying to get the element to load, and then move after three seconds. Instead, the element just moves immediately on the page load. Here is my code so far:
<!DOCTYPE html>
<html>
<style>
#container {
width: 400px;
height: 400px;
position: relative;
}
#animate {
width: 50px;
height: 50px;
position: absolute;
background-color: red;
}
</style>
<body id="body">
<div id="container">
<div id="animate"></div>
</div>
<script>
var elem = document.getElementById("animate");
function myMove(element) {
var posx = 0;
var posy = 25;
var opacity = 0;
var id = setInterval(frame, 40);
function frame() {
if (posx == 10) {
clearInterval(id);
} else {
posx++;
opacity = opacity + .1
element.style.top = posy + "%";
element.style.left = posx + "%";
element.style.opacity = opacity;
}
}
}
document.getElementById("body").addEventListener("load", setTimeout(myMove(elem), 3000))
</script>
</body>
</html>
Any help would be greatly appreciated.
You need to do
setTimeout(() => myMove(elem), 3000)
otherwise it sets a timeout for whatever myMove(elem) returns, which means myMove(elem) runs immediately
So basically you need this:
// Run at DOM loaded
document.addEventListener("DOMContentLoaded", function() {
console.log('DOM is loaded');
// Move
setTimeout(function(){ myMove(elem); }, 3000)
});
OR
// Run at full page load
window.addEventListener("load", function() {
console.log('Page is loaded');
// Move
setTimeout(function(){ myMove(elem); }, 3000)
});
Currently, the myMove methods execute immediately. To avoid this you can use arrow functions supported in ES6 or move myMove to a function
using arrow function (supported in ES6):
document.getElementById('body').addEventListener(
'load',
setTimeout(() => myMove(elem), 3000),
);
Convert to function
document.getElementById('body').addEventListener(
'load',
setTimeout(function () {
myMove(elem);
}, 3000),
);

Can't start and stop animation that runs in a constant loop

To simplify this question I have created two divs: when you click on the orange box the blue box below it will move back and forth in a continuous loop. What I want to be able to do is:
Click the orange box to start and STOP the blue box loop
After starting and stopping, the blue box will stop and continue each time where it left off.
I've tried just about everything and can't get it to work. Any advice would be greatly appreciated.
var hoverSlideBox = document.getElementById("hover_slide_box");
var slidingBox = document.getElementById("sliding_box");
hoverSlideBox.onclick = function() {
var pos = 0;
var moveLeft = false;
var stopAnimate = false;
init();
function init() {
setInterval(boxRight, 5);
}
function boxRight() {
if (!moveLeft) {
pos++;
slidingBox.style.left = pos + 'px';
}
if (pos == 500 || moveLeft) {
moveLeft = true;
boxLeft();
}
}
function boxLeft() {
if (moveLeft) {
pos--;
slidingBox.style.left = pos + 'px';
}
if (pos == 0 || !moveLeft) {
moveLeft = false;
}
}
}
<div id="hover_slide_box" style="background-color: #ff931e; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
<div id="sliding_box" style="top: 120px; background-color: #0071bc; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
You need to move some variables out of the onclick function so that they are not reset each time you click on the orange box. That, together with clearInterval, will give you a start/stop button.
var hoverSlideBox = document.getElementById("hover_slide_box");
var slidingBox = document.getElementById("sliding_box");
var running = false;
var intervalId;
var pos = 0;
var moveLeft = false;
hoverSlideBox.onclick = function() {
init();
function init() {
if (!running) {
intervalId = setInterval(boxRight, 5);
running = true;
} else {
clearInterval(intervalId);
running = false;
}
}
function boxRight() {
if (!moveLeft) {
pos++;
slidingBox.style.left = pos + 'px';
}
if (pos == 500 || moveLeft) {
moveLeft = true;
boxLeft();
}
}
function boxLeft() {
if (moveLeft) {
pos--;
slidingBox.style.left = pos + 'px';
}
if (pos == 0 || !moveLeft) {
moveLeft = false;
}
}
}
<div id="hover_slide_box" style="background-color: #ff931e; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
<div id="sliding_box" style="top: 120px; background-color: #0071bc; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
To do this, you can use clearInterval to stop the movement. To make it resume when you click again, you just need to have your position variable in a permanent scope (I move it to the global scope for simplicity).
Changed code:
var pos = 0;
var moveLeft = false;
var stopAnimate = false;
var slideInterval;
hoverSlideBox.onclick = function() {
init();
function init() {
if (slideInterval) {
clearInterval(slideInterval);
slideInterval = null;
} else {
slideInterval = setInterval(boxRight, 5);
}
}
Snippet:
var hoverSlideBox = document.getElementById("hover_slide_box");
var slidingBox = document.getElementById("sliding_box");
var pos = 0;
var moveLeft = false;
var stopAnimate = false;
var slideInterval;
hoverSlideBox.onclick = function() {
init();
function init() {
if (slideInterval) {
clearInterval(slideInterval);
slideInterval = null;
} else {
slideInterval = setInterval(boxRight, 5);
}
}
function boxRight() {
if (!moveLeft) {
pos++;
slidingBox.style.left = pos + 'px';
}
if (pos == 500 || moveLeft) {
moveLeft = true;
boxLeft();
}
}
function boxLeft() {
if (moveLeft) {
pos--;
slidingBox.style.left = pos + 'px';
}
if (pos == 0 || !moveLeft) {
moveLeft = false;
}
}
}
<div id="hover_slide_box" style="background-color: #ff931e; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
<div id="sliding_box" style="top: 120px; background-color: #0071bc; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
setInterval returns interval id which you can use to cancel the interval using clearInterval
You could cancel the timer as the other answer says, or use requestAnimationFrame which is specifically designed for animations like these. See documentation here
This way we can simply check if stopAnimating is set before queueing up our next frame. You could do the same thing with setInterval if you wanted to, but requestAnimationFrame is probably better.
var hoverSlideBox = document.getElementById("hover_slide_box");
var slidingBox = document.getElementById("sliding_box");
hoverSlideBox.onclick = function() {
var pos = 0;
var moveLeft = false;
var stopAnimate = false;
init();
function init() {
animate();
}
function animate(){
// stop animating without queueing up thenext frame
if (stopAnimate) return;
//queue up theh next frame.
requestAnimationFrame(boxRight);
}
function boxRight() {
if (!moveLeft) {
pos++;
slidingBox.style.left = pos + 'px';
}
if (pos == 500 || moveLeft) {
moveLeft = true;
boxLeft();
}
animate();
}
function boxLeft() {
if (moveLeft) {
pos--;
slidingBox.style.left = pos + 'px';
}
if (pos == 0 || !moveLeft) {
moveLeft = false;
}
}
}
<div id="hover_slide_box" style="background-color: #ff931e; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
<div id="sliding_box" style="top: 120px; background-color: #0071bc; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
Your code doesn't clear the interval when box is clicked again. setInterval executes a function every number of given seconds. To stop it, you have use the function clearInterval, passing the timer id that the function setInterval returned.
Also, your code can be better organized. I've refactorized it base in the following advices:
Don't use different functions for each direction. Your code have two different functions (moveLeft and moveRight) that are almost the same. Instead, use a simpler function that increments position given the current direction. Use a simple variable with the position increment, using -1 for left movement and +1 for right movement. If you have to modify the way the box moves you only have to change the moveBox function.
Use a function to check if the box have reached the boundaries. In general is good to have small functions that do one simple thing. In your code, boundaries check is splited in the two movement functions. In the proposed code the check code is a separate function where you can modify boundaries easily in the future if needed, instead of changing them in different places of your code.
Don't put all your logic in the click listener. Again, use simple functions that perform one simple task. The click listener should do a simple task, that's switching animation on and off. Initialization code should be in its onw function.
Again, for simplicity, use a simple function as the function executed by setInterval. If not, you would have to change the function that is executed by the setInterval function: moveRight when box is moving to the right and moveLeft when the box is moving to the left. This makes the code more complex and hard to debug and mantain.
Those advices are not very useful with a small code like this, but its benefits are more visible when your code gets more complex.
var hoverSlideBox = document.getElementById("hover_slide_box");
var slidingBox = document.getElementById("sliding_box");
var pos = 0;
var direction = 1;
var animate = false;
var intervalHandler;
hoverSlideBox.onclick = function() {
if (animate) {
stop();
}
else {
init();
}
}
function init() {
animate = true;
intervalHandler = setInterval(moveBox, 5);
}
function stop() {
animate = false;
clearInterval(intervalHandler);
}
function tic() {
if (animate) {
moveBox();
}
}
function checkBoundaries() {
if (pos == 500) {
direction = -1;
}
else if (pos == 0) {
direction = 1;
}
}
function moveBox() {
pos += direction;
slidingBox.style.left = pos + 'px';
checkBoundaries();
}
<div id="hover_slide_box" style="background-color: #ff931e; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
<div id="sliding_box" style="top: 120px; background-color: #0071bc; cursor: pointer; position: absolute; height: 100px; width: 100px;"></div>
Try this snippet, it should work aswell
var hoverSlideBox = document.getElementById("hover_slide_box");
var slidingBox = document.getElementById("sliding_box");
var moveLeft = false;
var pos = 0;
var intervalID = null;
hoverSlideBox.onclick = function(){
if (intervalID) {
clearInterval(intervalID);
intervalID = null;
} else {
intervalID = setInterval(function () {
pos += moveLeft ? -1 : 1;
slidingBox.style.left = pos + 'px';
moveLeft = pos >= 500 ? true : pos <= 0 ? false : moveLeft;
}, 5);
}
}
<div id="hover_slide_box" style="background-color: #ff931e; cursor: pointer; position: absolute; height: 100px; width: 100px;">
<div id="sliding_box" style="top: 120px; background-color: #0071bc; cursor: pointer; position: absolute; height: 100px; width: 100px;">

onClick event on image while already moving

I'm trying to make an image that moves to the right on my website. When you click the image, it should move to the left. For now, this doesn't happen, any ideas? If possible, in pure Javascript and no Jquery ;)
Also, if you click the image for a second time, it should move to the right again. Every consecutive time, the image should move to the other side. I guess this would be best with a for-loop?
<script type"text/javascript">
window.onload = init;
var winWidth = window.innerWidth - movingblockobject.scrollWidth; //get width of window
var movingblock = null //object
movingblock.onclick = moveBlockLeft();
function init() {
movingblock = document.getElementById('movingblockobject'); //get object
movingblock.style.left = '0px'; //initial position
moveBlockRight(); //start animiation
}
function moveBlockRight() {
if (parseInt(movingblock.style.left) < winWidth) { // stop function if element touches max window width
movingblock.style.left = parseInt(movingblock.style.left) + 10 + 'px'; //move right by 10px
setTimeout(moveBlockRight,20); //call moveBlockRight in 20 msec
} else {
return;
}
}
function moveBlockLeft () {
movingblock.style.right = parseInt(movingblock.style.right) + 10 + 'px'
}
</script>
Please first go through the Basics of javascript before trying out something .
window.onload = init;
var winWidth = window.innerWidth;
var movingblock = null;
var intervalid = null;
var isLeft = false;
function init() {
console.log('Init');
movingblock = document.getElementById('movingblockobject');
movingblock.style.left = '0px';
intervalid = setInterval(function() {
moveBlock(true);
}, 2000);
movingblock.onclick = function() {
moveBlock(false);
};
}
function moveBlock(isSetInterval) {
if (!isSetInterval)
isLeft = !isLeft;
if (parseInt(movingblock.style.left) < winWidth) {
if (isLeft)
movingblock.style.left = parseInt(movingblock.style.left) - 10 + 'px';
else
movingblock.style.left = parseInt(movingblock.style.left) + 10 + 'px';
} else {
movingblock.style.left = '0px';
}
}
function moveBlockLeft() {
clearInterval(intervalid);
movingblock.style.right = parseInt(movingblock.style.right) + 10 + 'px';
intervalid = setInterval(moveBlockRight, 20);
}
<div id="movingblockobject" style="width:50px;height:50px;border:solid;position: absolute;">
var movingblock = null
this are mistakes you have delclared it as null and next line you are binding click event.Also for assigning click event you should assign the name of the function.
movingblock.onclick = moveBlockLeft;
above is basic bug there are lot like the above.I feel Self learning is much better for basics
try yourself.
try the above it will work but please try yourself
You should CSS3 transition, works like a charm. Just toggle a class "right"
HTML:
<html>
<head>
<style>
#movingblockobject{
width: 40px;
padding: 10px;
position: fixed;
height:10px;
left:0px;
-webkit-transition: left 2s; /* For Safari 3.1 to 6.0 */
transition: left 2s;
}
#movingblockobject.right{
left:200px;
}
</style>
<script src="http://code.jquery.com/jquery-1.11.1.min.js"></script>
<script>
$( document ).ready(function() {
$('#movingblockobject').on('click', function (e) {
$('#movingblockobject').toggleClass("right");
});
});
</script>
</head>
<body>
<div id="movingblockobject" class="demo">add image here</div>
</body>
</html>

How to make marquee when hover in - text scroll and infinite loop, out - back to start position?

here is my jsfiddle http://jsfiddle.net/9XdV7/, how to make when hover in - text scroll and infinite loop, out - back to start position? now it can't infinite loop scroll
for (var i = 0; i < $('.list').length; i++) {
var this_el = $('.list').eq(i);
var interval = null;
$(this_el).hover(function() {
var that = $(this);
var this_indent = 0;
interval = setInterval(function(){
this_indent--;
if (this_indent == -($(that).find('.text').width())) {
clearInterval(interval);
this_indent = 0;
// how to loop scroll
}
$(that).css('text-indent', this_indent);
},20);
}, function() {
clearInterval(interval);
$(this).css('text-indent', 0);
});
}
html & css
<div class="list"><div class="text">stringstringstringstring</div></div>
<div class="list"><div class="text">stringstringstring</div></div>
<div class="list"><div class="text">stringstringstringstring</div></div>
.list {
width: 100px;
overflow: hidden;
white-space:nowrap;
height: 15px;
background-color: red;
margin: 10px;
}
.text {
text-align: left;
background-color: purple;
display: inline;
}
Is this what you're looking for? Fiddle
I used mouseenter and mouseleave instead of hover.
$(elem).on("mouseenter",function() { ... });
I stored the identifier belonging to the element in its data: $(this).data("interval",interval);
I added
if(this_indent < -150) {
this_indent = 100;
}
to make the effect infinite. -150 is a value I got from the developer tools. 100 is pure testing.
This still wants some tweaking for determining the point at which to loop, but I think it's basically what you want:
$(function() {
for (var i = 0; i < $('.list').length; i++) {
var this_el = $('.list').eq(i);
var interval = null;
$(this_el).hover(function() {
var that = $(this);
var this_indent = 0;
interval = setInterval(function(){
this_indent--;
if (this_indent < that.width() * -1)
this_indent = that.width();
that.css('text-indent', this_indent);
},20);
}, function() {
clearInterval(interval);
$(this).css('text-indent', 0);
});
}
});
It's looping based on the width of the div, rather than the actual length of the text. If you want the text width, you could look here: Calculating text width

Running a javascript function several times onmouseover

I have a function that moves a box when hovering a button. I would like the function to run over and over again every second as long as the mouse hovers over the button. I have tried loops too but I can't get this to work. I would be very thankful if you would look into this.
Here is my code:
<!DOCTYPE html>
<head>
<style>
#box {
position: relative;
top: 20px;
left: 10px;
width: 50px;
height: 50px;
background:#333366;
}
</style>
<script>
function Start() {
setInterval(Move('box'),1000);
}
var value = 0;
function Move(element) {
value += 50;
var box = document.getElementById(element);
box.style.transition = "left 0.2s ease-in-out 0s";
box.style.left = value+'px';
}
</script>
</head>
<body>
<button onmouseover="Start();">Hover to move</button>
<div id="box"></div>
</body>
</html>
Use this:
setInterval(function(){
Move('box')
},1000);
You have to pass a function to setInterval. You were actually calling Move and passing its return value.
something like this maybe?
http://jsfiddle.net/blackjim/HwKb3/1/
var value = 0,
timer,
btn = document.getElementById('btn');
btn.onmouseover = function(){
timer = setInterval(function(){
// your loop code here
Move('box');
}, 1000);
};
btn.onmouseout = function(){
clearInterval(timer);
}
function Move(element) {
value += 50;
var box = document.getElementById(element);
box.style.transition = "left 0.2s ease-in-out 0s";
box.style.left = value + 'px';
}
Try to see jQuery, it might help you in the beginning.
When this line
setInterval(Move('box'),1000);
is executed, Move('box') is evaluated (and executed one), therefore, your argument to setInterval is the return value for it, that is null
Try this:
var value = 0;
function move(element) {
value += 50;
var box = document.getElementById(element);
box.style.transition = "left 0.2s ease-in-out 0s";
box.style.left = value+'px';
// console.log(box);
}
var button = document.getElementById("buttonID");
button.onmouseover = function() {
this.iid = setInterval(function() {
move("boxID");
}, 1000);
};
button.onmouseout = function() {
this.iid && clearInterval(this.iid);
};

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