Develop Reference

Why does this jQuery code works only once?

I have this short jQuery code to make the picture disappear when the window is resized. For some reason, after it disappears, it doesn't appear again.
Here is the code:
$(document).ready(function(){
$(window).resize(function(){
if($(window).width() < 700) {
$("#side-pic").css("display","none");
} else if($(window).width() >= 700){
$("#side-pic").css("display","show");
}
});
});
Also if by any chance you know if there is a way to make picture move under a certain div in my code, I'll be glad to hear it! Thank you guys in advance!

There is no display property such as display: show. Try using $("#side-pic").css("display","block"); instead.
Another Alternative would be hide/show:
$(document).ready(function(){
$(window).resize(function(){
if($(window).width() < 700) {
$("#side-pic").hide();
}
else if($(window).width() >= 700) {
$("#side-pic").show();
}
});
});

That's because the "show" is not a valid display value. https://developer.mozilla.org/en-US/docs/Web/CSS/display
Also, why the else if, isn't an else good enough?
Or rather a reusable CSS class and jQuery's toggleClass() Method:
jQuery( $ => {
$(window).on('resize', function() {
$("#side-pic").toggleClass("is-hidden", $(this).width() < 700);
});
});
.is-hidden {display: none;}
<div id="side-pic">SIDE PIC</div>
<script src="//code.jquery.com/jquery-3.1.0.js"></script>

You can also write a code Like following
$(document).ready(function(){
$(window).resize(function(){
if($(window).width() < 700) {
$("#side-pic").hide();
} else if($(window).width() >= 700){
$("#side-pic").show();
}
});
});

How do I use multiple functions in jQuery?

I've added jQuery function that shows and hides navbar when scrolled. I also want to hide a div when the button 'start' is clicked. After i add new function none of them works longer. I have tried to add it to various places, but I still get no result at all. So how do I add multiple functions and make them to work?
Heres my code:
<script>
// function that hides text on click
(function($) {
$('#start').click(function() {
$('.lead').hide());
});
});
// my original function that stopped working after i added new one
(function($) {
$(document).ready(function() {
$(".masthead").css("background-color", "inherit");
// fade in .navbar
$(function() {
$(window).scroll(function() {
// set distance user needs to scroll before we fadeIn navbar
if($(this).scrollTop() > 600) {
$('.masthead').fadeIn();
$(".masthead").css("background-color", "black");
} else if($(this).scrollTop() === 0) {
$('.masthead').fadeIn();
$(".masthead").css("background-color", "inherit");
} else {
$('.masthead').fadeOut();
}
});
});
});
}(jQuery));
</script>

I think the problem is in the closing tag of the function you're adding.
Try like this:
(function ($){
$('#start').click(function(){
$('.lead').hide();
});
}(jQuery));
// my original function that stopped working after i added new one
(function ($) {
$(document).ready(function(){
$(".masthead").css("background-color","inherit");
// fade in .navbar
$(function () {
$(window).scroll(function () {
// set distance user needs to scroll before we fadeIn navbar
if ($(this).scrollTop() > 600) {
$('.masthead').fadeIn();
$(".masthead").css("background-color","black");
} else if($(this).scrollTop() === 0){
$('.masthead').fadeIn();
$(".masthead").css("background-color","inherit");
} else {
$('.masthead').fadeOut();
}
});
});
});
}(jQuery));

At least, closing bracket is wrong here. $('.lead').hide());
Tip: always check developer console first. Have fun coding.

Edit : Note that you have an extra closing bracket in the first function $('.lead').hide());.
You can use the following. Both functions can be combined in to a single block. And you can use $(document).ready() directly. If there is a problem with name conflict for $ use jQuery.noConflict();
<script>
$(document).ready(function() {
$(".masthead").css("background-color", "inherit");
// fade in .navbar
$('#start').click(function() {
$('.lead').hide();
});
$(window).scroll(function() {
// set distance user needs to scroll before we fadeIn navbar
if ($(this).scrollTop() > 600) {
$('.masthead').fadeIn();
$(".masthead").css("background-color", "black");
} else if ($(this).scrollTop() === 0) {
$('.masthead').fadeIn();
$(".masthead").css("background-color", "inherit");
} else {
$('.masthead').fadeOut();
}
});
});
</script>

Can't get scrolltop to work correctly

I've created a fiddle to show what is happening.
I am using jquery to fade in a link to the top of the page when the user is scrolling down.
I can get it to work on jsfiddle if I place the code in the javascript window, but if I put it in script tags where my $( window ).load(function() is in the HTML window, it doesn't work at all. Does anybody know why?
$('#slide').bind("scroll", function() {
if ($(this).scrollTop() > 20) {
$("#top").fadeIn();
} else {
$("#top").stop().fadeOut();
}
});
$('#top').on("click",function(){
$('#slide').animate({scrollTop:0}, 'slow');
});
here's the fiddle:
https://jsfiddle.net/8130fdhm/2/
Any help would be most appreciated.

Put in a script tag just before the body end tag. I have updated the jsfiddle here https://jsfiddle.net/8130fdhm/3/
....
<script>
$('#slide').bind("scroll", function() {
if ($(this).scrollTop() > 20) {
$("#top").fadeIn();
} else {
$("#top").stop().fadeOut();
}
});
$('#top').on("click",function(){
$('#slide').animate({scrollTop:0}, 'slow');
});
</script>
</body>

jquery : detecting scroll position

I want to get an alert when, while scrolling, my footer comes to view.
$(window).on("mousewheel", function(){
if ($(window).scrollTop() + $(window).height() > $('#footer').position().top){
alert("footer visible");
}
else{
alert("footer invisible");
}
});
http://jsfiddle.net/JRUnr/10/
All conditions with height seem right, but not during scrolling.

Working DEMO
Try this
$(window).scroll(function () {
if ($(window).scrollTop() + $(window).height() > $('.footer').offset().top) {
alert("footer visible");
} else {
alert("footer invisible");
}
});
Hope this helps,Thank you

There is a jquery plugin for this task named jQuery Waypoints
(http://imakewebthings.com/jquery-waypoints/)
$('#footer').waypoint(function(direction) {
alert('Top of thing hit top of viewport.');
});

here is a working fiddle...
http://jsfiddle.net/kasperfish/JRUnr/14/
it is hacked together but it works
flag=true;
$(window).scroll(function() {
st=$(window).scrollTop();
$('#topscroll').html(st)
if(st>1450){
if(flag)
alert('test');flag=false;
}
});

Fade in/out div scrollTop

I have a floating menu that i want to fade in when you start to scroll down the page, then fade out when you are back at the top of the page. I have got it working without the fade, but im not sure how to add the fades. Any help appreciated. Thanks.
$(document).scroll(function() {
$('#floatingnav').toggle($(this).scrollTop()>250)
});
css
#floatingnav {
position:fixed;
display:none;
}

You can use fadeToggle with some duration as an argument(just incase you want) instead of plane toggle.That will do your job.
$(document).scroll(function() {
$('#floatingnav').fadeToggle($(this).scrollTop()>250)
});

You can try this to test if div has reached top
$(window).scroll(function () {
var d = $('div'); // this is your fixed div
if (d.offset().top > 250) {
d.fadeIn();
} else {
d.stop().fadeOut();
}
});
TEST FIDDLE

$(window).bind("scroll", function() {
if ($(this).scrollTop() > 250) {
$("#floatingnav").fadeIn();
} else {
$("#floatingnav").stop().fadeOut();
}
});