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Is there a way to run a line of code after a marquee has finished scrolling once?

Is there a way to run a line of code after a marquee has finished scrolling its text one time? I was going to use it to whenever the text was gone I would remove the element in the queue index with the location of 0 and then use the marquee to show the next element in the queue. How would I do this?
I'm kinda new to coding, so please excuse me if this is a bad question to ask.
let scroller = document.getElementById("scrollText")
let news = function (news, id) {
this.text = news;
this.id = id;
}
let newsFeed = [
new news("Bob has slipped and fell once again. Oh dear.", 1),
new news("Alicia has lost her keys.", 2)
]
let queue = []
scroller.innerHTML = queue[0]
queue.append(newsFeed[Math.round(math.random) * newsFeed.length])
//Whenever the marquee is done scrolling
queue.pop()
scroller.innerHTML = queue[0];

as #WoIIe suggest you can check on the marquee element left position to find out if its finished scrolling, try doing somthing like this :
$(function () {
var numberofCycles = 0;
setInterval(function () {
var currentLeft = $('#scrollText').position().left;
if (currentLeft < 0 && numberofCycles == 0) {
numberofCycles += 1;
alert("One cycle finished!");
}
}, 100)
});

JavaScript Choose your own adventure game random number function in loop problem

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>

jQuery fade in box with unique content

I am making an info screen, and for that, it needs to show reviews from their customers pulled from Trustpilot.
I got the reviews and everything formatted in HTML showing the 20 latest, but I want to present it very sweet. I am not a JavaScript guru, but I thought i would do it using jQuery and its fadein function.
What is want, is have 20 unique divs fading in with X milliseconds difference popping randomly up. By unique I mean, that each div must have unique content. And by randomly popping up, I mean that if box 1 spawns first, then the next should be 5, then 14 etc, and then another cycle the next time around.
Just like what I made here;
$(function() {
var box = $('.box');
var delay = 100;
for (i = 0; i < 30; i++) {
setTimeout(function() {
var new_box = box.clone();
$('.container').append(new_box);
new_box.fadeIn();
}, delay);
delay += 500; // Delay the next box by an extra 500ms
}
});
http://jsfiddle.net/CCawh/5/
Is this even possible, and how would this be done?
I am very new to JavaScript, so please bear with me if I ask to much
Thanks in advance.
EDIT:
The HTML i want to spawn will all be wrapped in divs, so it would go like this;
<div id="one">content</div>
<div id="two">content</div>
<div id="three">content</div>
<div id="four">content</div>
etc.

Made up a nice function for you. I believe this may be what you are looking for
Here's a rundown of how it works :
Populate an array with numbers randomly generated 1-10 in this case.
Run through that array with a set interval, and when everything has
been added stop the interval
pretty straightforward from there. Set the visibility etc. You should be able to change up the function to dynamically add HTML elements and what-not, but just giving you something to start with.
var usedNum = [];
var i, j, y;
i = 0;
for(y = 0; y < 10; y++){
var x = Math.floor((Math.random() * 10) + 1);
if(!isUsed(x)) usedNum.push(x);
else y--;
}
var showInterval = setInterval ( function(){
if(i == 10){
clearInterval(showInterval);
}
$(".container div[data-line='" + usedNum[i] + "']").css({opacity: 0.0, visibility: "visible"}).animate({opacity: 1.0});
i++;
}, 500);
function isUsed(num) {
var used = false;
for(j = 0; j < usedNum.length; j++){
if(usedNum[j] == num){
used = true;
}
}
return used;
}
Demo fiddle : http://jsfiddle.net/xS39F/3/
Edit:
You can also mess around with the speed of the animation. In this demo (http://jsfiddle.net/adjit/XYU34/1/) I set the speed to 1000 so the next element starts fading in before the last element was done fading in. Makes it look a little smoother.

Instead of using a for loop and setTimeout, would setInterval work better for what you need? Some HTML might help better understand what you're trying to achieve.
$(function() {
var box = $('.box');
var delay = 100;
var interval = setInterval(function() {
var new_box = box.clone();
$('.container').append(new_box);
new_box.fadeIn();
}, delay);
delay += 500; // Delay the next box by an extra 500ms
}, delay);
});

ReactJS: Modeling Bi-Directional Infinite Scrolling

Our application uses infinite scrolling to navigate large lists of heterogenous items. There are a few wrinkles:
It's common for our users to have a list of 10,000 items and need to scroll through 3k+.
These are rich items, so we can only have a few hundred in the DOM before browser performance becomes unacceptable.
The items are of varying heights.
The items may contain images and we allow the user to jump to a specific date. This is tricky because the user can jump to a point in the list where we need to load images above the viewport, which would push the content down when they load. Failing to handle that means that the user may jump to a date, but then be shifted to an earlier date.
Known, incomplete solutions:
(react-infinite-scroll) - This is just a simple "load more when we hit the bottom" component. It does not cull any of the DOM, so it will die on thousands of items.
(Scroll Position with React) - Shows how to store and restore the scroll position when inserting at the top or inserting at the bottom, but not both together.
I'm not looking for the code for a complete solution (although that would be great.) Instead, I'm looking for the "React way" to model this situation. Is scroll position state or not? What state should I be tracking to retain my position in the list? What state do I need to keep so that I trigger a new render when I scroll near the bottom or top of what is rendered?

This is a mix of an infinite table and an infinite scroll scenario. The best abstraction I found for this is the following:
Overview
Make a <List> component that takes an array of all children. Since we do not render them, it's really cheap to just allocate them and discard them. If 10k allocations is too big, you can instead pass a function that takes a range and return the elements.
<List>
{thousandelements.map(function() { return <Element /> })}
</List>
Your List component is keeping track of what the scroll position is and only renders the children that are in view. It adds a large empty div at the beginning to fake the previous items that are not rendered.
Now, the interesting part is that once an Element component is rendered, you measure its height and store it in your List. This lets you compute the height of the spacer and know how many elements should be displayed in view.
Image
You are saying that when the image are loading they make everything "jump" down. The solution for this is to set the image dimensions in your img tag: <img src="..." width="100" height="58" />. This way the browser doesn't have to wait to download it before knowing what size it is going to be displayed. This requires some infrastructure but it's really worth it.
If you can't know the size in advance, then add onload listeners to your image and when it is loaded then measure its displayed dimension and update the stored row height and compensate the scroll position.
Jumping at a random element
If you need to jump at a random element in the list that's going to require some trickery with scroll position because you don't know the size of the elements in between. What I suggest you to do is to average the element heights you already have computed and jump to the scroll position of last known height + (number of elements * average).
Since this is not exact it's going to cause issues when you reach back to the last known good position. When a conflict happens, simply change the scroll position to fix it. This is going to move the scroll bar a bit but shouldn't affect him/her too much.
React Specifics
You want to provide a key to all the rendered elements so that they are maintained across renders. There are two strategies: (1) have only n keys (0, 1, 2, ... n) where n is the maximum number of elements you can display and use their position modulo n. (2) have a different key per element. If all the elements share a similar structure it's good to use (1) to reuse their DOM nodes. If they don't then use (2).
I would only have two pieces of React state: the index of the first element and the number of elements being displayed. The current scroll position and the height of all the elements would be directly attached to this. When using setState you are actually doing a rerender which should only happen when the range changes.
Here is an example of infinite list using some of the techniques I describe in this answer. It's going to be some work but React is definitively a good way to implement an infinite list :)

have a look at http://adazzle.github.io/react-data-grid/index.html#
This looks like a powerful and performant datagrid with Excel-like features and lazy loading/optimized rendering (for millions of rows) with rich editing features (MIT licenced).
Not yet tried in our project but will do so pretty soon.
A great resource to search for things like these is also http://react.rocks/
In this case, a tag search is helpful:
http://react.rocks/tag/InfiniteScroll

I was facing a similar challenge for modeling single-direction infinite scrolling with heterogeneous item heights and so made an npm package out of my solution:
https://www.npmjs.com/package/react-variable-height-infinite-scroller
and a demo: http://tnrich.github.io/react-variable-height-infinite-scroller/
You can check out the source code for the logic, but I basically followed the recipe #Vjeux outlined in the above answer. I haven't yet tackled jumping to a particular item, but I'm hoping to implement that soon.
Here's the nitty-gritty of what the code currently looks like:
var React = require('react');
var areNonNegativeIntegers = require('validate.io-nonnegative-integer-array');
var InfiniteScoller = React.createClass({
propTypes: {
averageElementHeight: React.PropTypes.number.isRequired,
containerHeight: React.PropTypes.number.isRequired,
preloadRowStart: React.PropTypes.number.isRequired,
renderRow: React.PropTypes.func.isRequired,
rowData: React.PropTypes.array.isRequired,
},
onEditorScroll: function(event) {
var infiniteContainer = event.currentTarget;
var visibleRowsContainer = React.findDOMNode(this.refs.visibleRowsContainer);
var currentAverageElementHeight = (visibleRowsContainer.getBoundingClientRect().height / this.state.visibleRows.length);
this.oldRowStart = this.rowStart;
var newRowStart;
var distanceFromTopOfVisibleRows = infiniteContainer.getBoundingClientRect().top - visibleRowsContainer.getBoundingClientRect().top;
var distanceFromBottomOfVisibleRows = visibleRowsContainer.getBoundingClientRect().bottom - infiniteContainer.getBoundingClientRect().bottom;
var rowsToAdd;
if (distanceFromTopOfVisibleRows < 0) {
if (this.rowStart > 0) {
rowsToAdd = Math.ceil(-1 * distanceFromTopOfVisibleRows / currentAverageElementHeight);
newRowStart = this.rowStart - rowsToAdd;
if (newRowStart < 0) {
newRowStart = 0;
}
this.prepareVisibleRows(newRowStart, this.state.visibleRows.length);
}
} else if (distanceFromBottomOfVisibleRows < 0) {
//scrolling down, so add a row below
var rowsToGiveOnBottom = this.props.rowData.length - 1 - this.rowEnd;
if (rowsToGiveOnBottom > 0) {
rowsToAdd = Math.ceil(-1 * distanceFromBottomOfVisibleRows / currentAverageElementHeight);
newRowStart = this.rowStart + rowsToAdd;
if (newRowStart + this.state.visibleRows.length >= this.props.rowData.length) {
//the new row start is too high, so we instead just append the max rowsToGiveOnBottom to our current preloadRowStart
newRowStart = this.rowStart + rowsToGiveOnBottom;
}
this.prepareVisibleRows(newRowStart, this.state.visibleRows.length);
}
} else {
//we haven't scrolled enough, so do nothing
}
this.updateTriggeredByScroll = true;
//set the averageElementHeight to the currentAverageElementHeight
// setAverageRowHeight(currentAverageElementHeight);
},
componentWillReceiveProps: function(nextProps) {
var rowStart = this.rowStart;
var newNumberOfRowsToDisplay = this.state.visibleRows.length;
this.props.rowData = nextProps.rowData;
this.prepareVisibleRows(rowStart, newNumberOfRowsToDisplay);
},
componentWillUpdate: function() {
var visibleRowsContainer = React.findDOMNode(this.refs.visibleRowsContainer);
this.soonToBeRemovedRowElementHeights = 0;
this.numberOfRowsAddedToTop = 0;
if (this.updateTriggeredByScroll === true) {
this.updateTriggeredByScroll = false;
var rowStartDifference = this.oldRowStart - this.rowStart;
if (rowStartDifference < 0) {
// scrolling down
for (var i = 0; i < -rowStartDifference; i++) {
var soonToBeRemovedRowElement = visibleRowsContainer.children[i];
if (soonToBeRemovedRowElement) {
var height = soonToBeRemovedRowElement.getBoundingClientRect().height;
this.soonToBeRemovedRowElementHeights += this.props.averageElementHeight - height;
// this.soonToBeRemovedRowElementHeights.push(soonToBeRemovedRowElement.getBoundingClientRect().height);
}
}
} else if (rowStartDifference > 0) {
this.numberOfRowsAddedToTop = rowStartDifference;
}
}
},
componentDidUpdate: function() {
//strategy: as we scroll, we're losing or gaining rows from the top and replacing them with rows of the "averageRowHeight"
//thus we need to adjust the scrollTop positioning of the infinite container so that the UI doesn't jump as we
//make the replacements
var infiniteContainer = React.findDOMNode(this.refs.infiniteContainer);
var visibleRowsContainer = React.findDOMNode(this.refs.visibleRowsContainer);
var self = this;
if (this.soonToBeRemovedRowElementHeights) {
infiniteContainer.scrollTop = infiniteContainer.scrollTop + this.soonToBeRemovedRowElementHeights;
}
if (this.numberOfRowsAddedToTop) {
//we're adding rows to the top, so we're going from 100's to random heights, so we'll calculate the differenece
//and adjust the infiniteContainer.scrollTop by it
var adjustmentScroll = 0;
for (var i = 0; i < this.numberOfRowsAddedToTop; i++) {
var justAddedElement = visibleRowsContainer.children[i];
if (justAddedElement) {
adjustmentScroll += this.props.averageElementHeight - justAddedElement.getBoundingClientRect().height;
var height = justAddedElement.getBoundingClientRect().height;
}
}
infiniteContainer.scrollTop = infiniteContainer.scrollTop - adjustmentScroll;
}
var visibleRowsContainer = React.findDOMNode(this.refs.visibleRowsContainer);
if (!visibleRowsContainer.childNodes[0]) {
if (this.props.rowData.length) {
//we've probably made it here because a bunch of rows have been removed all at once
//and the visible rows isn't mapping to the row data, so we need to shift the visible rows
var numberOfRowsToDisplay = this.numberOfRowsToDisplay || 4;
var newRowStart = this.props.rowData.length - numberOfRowsToDisplay;
if (!areNonNegativeIntegers([newRowStart])) {
newRowStart = 0;
}
this.prepareVisibleRows(newRowStart , numberOfRowsToDisplay);
return; //return early because we need to recompute the visible rows
} else {
throw new Error('no visible rows!!');
}
}
var adjustInfiniteContainerByThisAmount;
//check if the visible rows fill up the viewport
//tnrtodo: maybe put logic in here to reshrink the number of rows to display... maybe...
if (visibleRowsContainer.getBoundingClientRect().height / 2 <= this.props.containerHeight) {
//visible rows don't yet fill up the viewport, so we need to add rows
if (this.rowStart + this.state.visibleRows.length < this.props.rowData.length) {
//load another row to the bottom
this.prepareVisibleRows(this.rowStart, this.state.visibleRows.length + 1);
} else {
//there aren't more rows that we can load at the bottom so we load more at the top
if (this.rowStart - 1 > 0) {
this.prepareVisibleRows(this.rowStart - 1, this.state.visibleRows.length + 1); //don't want to just shift view
} else if (this.state.visibleRows.length < this.props.rowData.length) {
this.prepareVisibleRows(0, this.state.visibleRows.length + 1);
}
}
} else if (visibleRowsContainer.getBoundingClientRect().top > infiniteContainer.getBoundingClientRect().top) {
//scroll to align the tops of the boxes
adjustInfiniteContainerByThisAmount = visibleRowsContainer.getBoundingClientRect().top - infiniteContainer.getBoundingClientRect().top;
// this.adjustmentScroll = true;
infiniteContainer.scrollTop = infiniteContainer.scrollTop + adjustInfiniteContainerByThisAmount;
} else if (visibleRowsContainer.getBoundingClientRect().bottom < infiniteContainer.getBoundingClientRect().bottom) {
//scroll to align the bottoms of the boxes
adjustInfiniteContainerByThisAmount = visibleRowsContainer.getBoundingClientRect().bottom - infiniteContainer.getBoundingClientRect().bottom;
// this.adjustmentScroll = true;
infiniteContainer.scrollTop = infiniteContainer.scrollTop + adjustInfiniteContainerByThisAmount;
}
},
componentWillMount: function(argument) {
//this is the only place where we use preloadRowStart
var newRowStart = 0;
if (this.props.preloadRowStart < this.props.rowData.length) {
newRowStart = this.props.preloadRowStart;
}
this.prepareVisibleRows(newRowStart, 4);
},
componentDidMount: function(argument) {
//call componentDidUpdate so that the scroll position will be adjusted properly
//(we may load a random row in the middle of the sequence and not have the infinte container scrolled properly initially, so we scroll to the show the rowContainer)
this.componentDidUpdate();
},
prepareVisibleRows: function(rowStart, newNumberOfRowsToDisplay) { //note, rowEnd is optional
//setting this property here, but we should try not to use it if possible, it is better to use
//this.state.visibleRowData.length
this.numberOfRowsToDisplay = newNumberOfRowsToDisplay;
var rowData = this.props.rowData;
if (rowStart + newNumberOfRowsToDisplay > this.props.rowData.length) {
this.rowEnd = rowData.length - 1;
} else {
this.rowEnd = rowStart + newNumberOfRowsToDisplay - 1;
}
// var visibleRows = this.state.visibleRowsDataData.slice(rowStart, this.rowEnd + 1);
// rowData.slice(rowStart, this.rowEnd + 1);
// setPreloadRowStart(rowStart);
this.rowStart = rowStart;
if (!areNonNegativeIntegers([this.rowStart, this.rowEnd])) {
var e = new Error('Error: row start or end invalid!');
console.warn('e.trace', e.trace);
throw e;
}
var newVisibleRows = rowData.slice(this.rowStart, this.rowEnd + 1);
this.setState({
visibleRows: newVisibleRows
});
},
getVisibleRowsContainerDomNode: function() {
return this.refs.visibleRowsContainer.getDOMNode();
},
render: function() {
var self = this;
var rowItems = this.state.visibleRows.map(function(row) {
return self.props.renderRow(row);
});
var rowHeight = this.currentAverageElementHeight ? this.currentAverageElementHeight : this.props.averageElementHeight;
this.topSpacerHeight = this.rowStart * rowHeight;
this.bottomSpacerHeight = (this.props.rowData.length - 1 - this.rowEnd) * rowHeight;
var infiniteContainerStyle = {
height: this.props.containerHeight,
overflowY: "scroll",
};
return (
<div
ref="infiniteContainer"
className="infiniteContainer"
style={infiniteContainerStyle}
onScroll={this.onEditorScroll}
>
<div ref="topSpacer" className="topSpacer" style={{height: this.topSpacerHeight}}/>
<div ref="visibleRowsContainer" className="visibleRowsContainer">
{rowItems}
</div>
<div ref="bottomSpacer" className="bottomSpacer" style={{height: this.bottomSpacerHeight}}/>
</div>
);
}
});
module.exports = InfiniteScoller;

jQuery slider - last to first transition

I created this slider (didn't want to use plugins):
function slider(sel, intr, i) {
var _slider = this;
this.ind = i;
this.selector = sel;
this.slide = [];
this.slide_active = 0;
this.amount;
this.selector.children().each(function (i) {
_slider.slide[i] = $(this);
$(this).hide();
})
this.run();
}
slider.prototype.run = function () {
var _s = this;
this.slide[this.slide_active].show();
setTimeout(function () {
_s.slide[_s.slide_active].hide()
_s.slide_active++;
_s.run();
}, interval);
}
var slides = [];
var interval = 1000
$('.slider').each(function (i) {
slides[i] = new slider($(this), interval, i);
})
The problem I have is that I don´t know how to get it after the last slide(image), it goes back to the first slide again. Right now, it just .hide and .show till the end and if there is no image it just doesn´t start again.
Can someone help me out with a code suggestion to make it take the .length of the slider(the number of images on it) and if it is the last slide(image), then goes back to the first slide(image)... like a cycle.
Edit: Slider markup
<div class="small_box top_right slider">
<img class="fittobox" src="img/home10.jpg" alt="home10" width="854" height="592">
<img class="fittobox" src="img/home3.jpg" alt="home3" width="435" height="392">
<img class="fittobox" src="img/home4.jpg" alt="home4" width="435" height="392">
</div>

Created a fixed version for you here.
The easiest way to do this is to run a simple maths operation where you currently have
_s.slide_active++;
Instead, I get _s.slide_active, add 1, then run that through modulus (%) to the total length — which gives the remainder:
_s.slide_active = (_s.slide_active + 1) % _s.slide.length;

Take a look at this Fiddle link, this will help you create the slider in a cyclic way.If the slider reaches the last image it will start again from the first image.
var index = $selector.index();
if (index == (length - 1)) {
$('img').first().removeClass('invisible').addClass('visible');
}
I hope this will help you more. All the best.

You need to get to 0 after length-1.
One simple way to do that is to work modulo length:
_s.slide_active++;
_s.slide_active %= length;

not tested but hope helpful :
function slider(sel, intr , i){
...
this.count = this.selector.children().length;
this.run();
}
slider.prototype.run = function(){
var _s = this;
this.slide[this.slide_active].show();
setTimeout(function(){
_s.slide[_s.slide_active].hide()
if(_s.slide_active == this.count)
_s.slide_active = 0;
else
_s.slide_active++;
_s.run();
}, interval);
}