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Add/Remove Class of Nav Objects on Page Scroll

I am trying to change classes of objects in my navbar on scroll for a website I am developing. Basically, when I scroll to certain parts of a webpage I want the links to appear active and to remove the active class when they have been scrolled over.
I have managed to get the links to appear active but can't get it too remove the class. This is what I have so far but it isn't working:
$(document).on('scroll', function() {
if ($(this).scrollTop() >= $('#cards').position().top) {
$("#navcard").addClass("active");;
} else {
$("navcard").removeClass("active")
}
if ($(this).scrollTop() >= $('#projects').position().top) {
$("#navprojects").addClass("active");;
} else {
$("navprojects").removeClass("active")
}
if ($(this).scrollTop() >= $('#dave').position().top) {
$("#navdave").addClass("active");;
} else {
$("navdave").removeClass("active")
}
})
#cards,
#projects,
#dave {
height: 300px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="navacard">My navacard</div>
<div id="navprojects">My navprojects</div>
<div id="navdave">My navdave</div>
<br>
<div id="cards">My navacard</div>
<div id="projects">My navprojects</div>
<div id="dave">My navdave</div>
I hope someone can help.
Edit: this is what is now happening:

You forgot to add the # in the removeClass parts:
$(document).on('scroll', function() {
if ($(this).scrollTop() >= $('#cards').position().top) {
$("#navcard").addClass("active");;
} else {
$("#navcard").removeClass("active")
}
if ($(this).scrollTop() >= $('#projects').position().top) {
$("#navprojects").addClass("active");;
} else {
$("#navprojects").removeClass("active")
}
if ($(this).scrollTop() >= $('#dave').position().top) {
$("#navdave").addClass("active");;
} else {
$("#navdave").removeClass("active")
}
})
Update
Try changing your code to this and let me know what the results of each console.log is:
$(document).on('scroll', function() {
console.log($(this).scrollTop());
console.log($('#cards').position().top);
console.log($('#projects').position().top);
console.log($('#dave').position().top);
if ($(this).scrollTop() >= $('#cards').position().top) {
$("#navcard").addClass("active");;
} else {
$("#navcard").removeClass("active")
}
if ($(this).scrollTop() >= $('#projects').position().top) {
$("#navprojects").addClass("active");;
} else {
$("#navprojects").removeClass("active")
}
if ($(this).scrollTop() >= $('#dave').position().top) {
$("#navdave").addClass("active");;
} else {
$("#navdave").removeClass("active")
}
})

How to fix jQuery multiple else if statements not working

I am trying to run this function but it doesn't reach the first else if when I reach the specified screen size, it will continue to use the first if.
$(window).resize(function() {
function removeClass() {
$('#cookbook_add').removeClass('st-remove-label');
$('#email_page').removeClass('st-remove-label');
}
function addClass() {
$('#cookbook_add').addClass('st-remove-label');
$('#email_page').addClass('st-remove-label');
}
function addRemoveLabel() {
lastWidth = $(window).width();
if (lastWidth < 1150) {
console.log('1150');
addClass();
} else if (lastWidth < 975) {
console.log('975');
removeClass();
} else if (lastWidth < 680) {
console.log('680');
addClass();
} else {
removeClass();
}
}
addRemoveLabel();
});
I expect the console logs to fire when the screen is that size, but it doesn't.

You should specify a range greater than and lower than for each of the if statements
$(window).resize(function() {
function removeClass() {
$('#cookbook_add').removeClass('st-remove-label');
$('#email_page').removeClass('st-remove-label');
}
function addClass() {
$('#cookbook_add').addClass('st-remove-label');
$('#email_page').addClass('st-remove-label');
}
function addRemoveLabel() {
lastWidth = $(window).width();
if (lastWidth < 1150 && lastWidth > 975) {
console.log('1150');
addClass();
} else if (lastWidth < 975 && lastWidth > 680) {
console.log('975');
removeClass();
} else if (lastWidth < 680) {
console.log('680');
addClass();
} else {
removeClass();
}
}
addRemoveLabel();
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js"></script>
JSFiddle: https://jsfiddle.net/on0pet6g/

The problem is that the first if will be reached with any number < 1150... so 975 is < than 1150, 680 is < than 1150.
The best way is to compare the lowest values first like that:
if (lastWidth < 680) {
console.log('680');
addClass();
}
else if (lastWidth < 975) {
console.log('975');
removeClass();
}
else if (lastWidth < 1150) {
console.log('1150');
addClass();
}
else {
removeClass();
}
Just change the order.

Change the function to
function addRemoveLabel() {
lastWidth = $(window).width();
if (lastWidth <= 1150 && lastWidth > 975) {
console.log('1150');
addClass();
} else if (lastWidth <= 975 &&lastWidth > 680) {
console.log('975');
removeClass();
} else if (lastWidth <= 680) {
console.log('680');
addClass();
} else {
removeClass();
}
}

Creating multiple if/else conditions using javascript

I'm having an issue on how I can set multiple conditions. Basically I have three conditions that would read or listen to browser viewport. The first and second conditions are working but the third condition doesn't seem to trigger. Is it because of the conflict with the second condition?
if($(window).width() > 1280) {
console.log('desktop');
}
else if ($(window).width() < 1280) {
console.log('tablet');
}
else if ($(window).width() < 780) {
console.log('mobile');
}

It is because of your second else/if. If $(window).width() is less than 780, it is also less than 1280
Change it to
else if ( $(window).width() >= 780 && $(window).width() < 1280) {
console.log('tablet');
}

Your second condition also includes the third one. Because every value which is below 780 is also below 1280. You need something like windowWidth < 1280 && windowWidth >= 780 to give the range.
const windowWidth = $(window).width();
if(windowWidth > 1280) {
console.log('desktop');
} else if (windowWidth < 1280 && windowWidth >= 780 ) {
console.log('tablet');
} else if (windowWidth < 780) {
console.log('mobile');
}
Also it will be good to keep the window into a variable, not every time use with jQuery.

Here is a more concise example, but the condition rely on the order, some people do not like this style, but I think it is OK, and we can add a comment.
//Do not change the condition order
if($(window).width() <= 780) {
console.log('mobile');
}
else if ($(window).width() <= 1280) {
console.log('tablet');
}
else {
console.log('desktop');
}
Edited: The condition should be * than and equal to ....

There is flaw in your second condition...below is the fix..hope it helps!!
if($(window).width() > 1280) {
console.log('desktop');
}
else if ($(window).width() < 1280 && $(window).width() >= 780) {
console.log('tablet');
}
else if ($(window).width() < 780) {
console.log('mobile');
}

It's because the condition before < 780 is also met (ie. If the width is equal to 600 its inferior to 1280). Change the condition order or, better, improve the second condition :
if($(window).width() >= 1280) {
console.log('desktop');
}
else if ($(window).width() < 1280 && $(window).width() >= 780) {
console.log('tablet');
}
else if ($(window).width() < 780) {
console.log('mobile');
}
You also forgot a case, if the user's screen resolution is equal to 1280, you'll never enter any of your conditions. I change > to >= to include that case.

you can try this also, it will satisfy your second condition
if ($(window).width() > 1280) {
console.log('desktop');
}
else if ($(window).width() < 1280) {
if ($(window).width() < 780) {
console.log('mobile');
} else {
console.log('tablet');
}
}
or
if ($(window).width() > 1280) {
console.log('desktop');
}
else {
if ($(window).width() < 780) {
console.log('mobile');
} else {
console.log('tablet');
}
}

The correct way to do this would be to move your third condition up to the second spot.
When doing this kind of checks always place the most restricting condition first.
In your case, the tidiest way is:
var w = $(window).width();
if (w < 780) { // most restrictive condition. Excludes all the others...
console.log('mobile');
} else if (w < 1280) { // this one includes the one above but it will never be triggered if w < 780
console.log('tablet');
} else { // all the other cases
console.log('desktop');
}
Contrary to what many said, there is no need for this else if statement:
else if (windowWidth < 1280 && windowWidth >= 780) { ... }
This adds an unnecessary, redundant check.
It sure is a light operation, but imagine that, instead of windowWidth < 1280 you were checking
functionForCalculatingWidth() : int {
// huge amount of lines with expensive computation
return result;
}
you would be calling the same function twice. See why it is bad design?
In the same way, if you were to check conditions based on the largest element (plus let's add another fictional condition), you would do:
var w = $(window).width();
if (w > 1280) {
console.log('desktop');
} else if (w > 990) {
console.log('weird device');
} else if (w > 780) {
console.log('tablet');
} else {
console.log('mobile');
}

Hope this will satisfy you you can check this.
Different is this shows width in console easy to understand this logic if you cant understand let me know
Here is fiddle
$(window).bind("resize", function() {
sizewindow = $(this).width();
console.log(sizewindow)
if (sizewindow < 780) {
console.log('mobile');
} else if (780 < sizewindow < 1280) {
console.log('szechuan sauce');
if (sizewindow > 1280) {
console.log('rick and morty gone for 2 years sad af')
}
}
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

Scroll to the bottom of the page with offset - function running multiple times

I have some function, which checks if user scrolls to the bottom of the page, if yes, ajax runs and portion of result is added into current page.
This works well, but if i will add negative number to start this function faster, getData() function runs many times, and also all code starts to act strange - you can scroll up by one pixel and this runs again. Below working version without offset, and next with offset which is better for me as function starts earlier, but with loading getData() many times, which is wrong.
I think about some solution with flag - true / false, but i can't figure how do this properly.
$(window).scroll(function() {
if ((window.innerHeight + window.scrollY) >= document.body.offsetHeight) {
console.log(counter)
if (counter > sum) {
return false;
} else {
getData(counter);
counter++;
}
}
});
$(window).scroll(function() {
if ((window.innerHeight + window.scrollY) >= document.body.offsetHeight - 300) {
console.log(counter)
if (counter > sum) {
return false;
} else {
getData(counter);
counter++;
//$(window).unbind('scroll');
}
}
});

Thank you for debouncing tip.
Thanks to this, i was able to fix my code and all works well now.
Below example:
$(window).scroll(function() {
var timer;
if (timer) {
window.clearTimeout(timer);
}
timer = window.setTimeout(function() {
if ($(window).scrollTop() >= $(document).height() - $(window).height() - 500) {
console.log(counter)
if (counter > sum) {
return false;
} else {
getData(counter);
counter++;
}
}
}, 200);
});

jQuery page scroll event logic -- how to throttle

I have some jQuery listeners setup as follows:
$(document).scroll(function() {
if( $(this).scrollTop() < change1) {
updateBarChart('valuem', 'opencomparison');
} else if ( $(this).scrollTop() > change1 && $(this).scrollTop() < change2) {
updateBarChart('valuef', 'opencomparison');
} else if ($(this).scrollTop() > change2) {
updateBarChart('valuem', 'remove')
//updateSteamChart('','steam')
}
});
Straightforward enough. Some charts are updated when scrolling changes.
My issue is, this is sending too many function updates. I'd like if there were a way to throttle the .scroll(function() {}) That way, fewer event updates are fired.
Ideas?

A fairly simple way of achieving throttling might be to add a check against a random value so that it only fires a certain percentage of the time:
$(document).scroll(function() {
//Only fires 10% of the time
if (Math.random() < 0.1) {
if( $(this).scrollTop() < change1) {
updateBarChart('valuem', 'opencomparison');
} else if ( $(this).scrollTop() > change1 && $(this).scrollTop() < change2) {
updateBarChart('valuef', 'opencomparison');
} else if ($(this).scrollTop() > change2) {
updateBarChart('valuem', 'remove');
}
}
});
Alternatively, you could use a timer so that it only fires once per x miliseconds:
$(document).scroll(function() {
//Only fires at most once every half-second
if (timer > 500) {
timer = 0;
if( $(this).scrollTop() < change1) {
updateBarChart('valuem', 'opencomparison');
} else if ( $(this).scrollTop() > change1 && $(this).scrollTop() < change2) {
updateBarChart('valuef', 'opencomparison');
} else if ($(this).scrollTop() > change2) {
updateBarChart('valuem', 'remove');
}
}
});
var timer = 0;
setInterval(function () { timer += 50; }, 50);