How to refresh a page when crossing a certain width threshold? - javascript

I'm looking to refresh (reload) the page when the user's window size gets to 570px. I'm building a responsive website and need to do this (I haven't got time to go into detail about the why).
Basically, what I'm looking for is for the webpage to refresh ONCE when the window size crosses 570px width (once when it gets smaller, and once when it gets bigger).
I know this isn't ideal and it's something that should be avoided, but for this particular site, it will solve all my problems.

I would not do this myself, but you can use the following on page load (or document ready):
var threshold = 570;
var initialDiff = ($(window).width() > threshold) ? 1:-1;
$(window).on('resize',function(e){
var w = $(window).width();
var currentDiff = w - threshold;
if(currentDiff*initialDiff < 0) {
location.reload();
}
});
This works in both directions.
See this jsFiddle for an example where the indicator div is highlighted when the width crosses the threshold.

you can try this:
$(window).resize(function() {
if($(window).width()>570)
location.reload();//reload current page
});

Related

jQuery Change top value on scroll

I am hoping to create an effect similar to this one further down the page, in the 'Designing For 20-Somethings' section.
The effect is essentially to get a long image to change the css top value within a device such as a MacBook or iPhone, so it appears as though the image within the device is also scrolling whilst the user is scrolling the website.
I've created a fiddle to show how far I've got, but this doesn't work well on resize or when initially loaded.
This is some of the code I am using below
var yOffset = $element.offset().top - ($(document).scrollTop() + $(window).height()/diviser)
Any help is appreciated.
OK I see it now. But the movement is so subtle i didn't even notice it. It looks to be a lot of work for something that is pretty much unnoticeable. It appears he's changing the top position of the image based on some percentage change of the full window scroll but only when the image is inside the viewport.
Just off the top of my head (completely untested) something like this would scroll the image up and 1/4 the speed the window would scroll;
var mobiletop = $('.mobile').position().top;
var scrollfactor = 4;
$(window).scroll(function(){
if($(window).scrollTop() > mobiletop){
var imgtop = $('.mobile img').position().top - (($(window).scrollTop() - mobiletop)/scrollfactor);
$('.mobile img').css('top', imgtop + 'px');
}

jQuery window resize function not working

Sorry in advance if this is a minor question, but I'm new to javascript. I'm writing code for a webpage with full-width color backgrounds. Essentially, what I'm trying to do is detect the height of the window, and then make sure that the color block is the size of the window. The function works well on page load.
The problem is when I shrink the window, the div height doesn't change with the window size. I get all sorts of errors, like graphics poking out from behind the div.
I think what I'm missing is a way to detect the height of the content within each div and resize the height accordingly.
You can see how it works at http://pressshoppr.com
Here's the code:
$(function(){
var windowH = $(window).height();
if(windowH > wrapperH) {
$('.fullWidthSectionBG').css({'height':($(window).height())+'px'});
$('.fullWidthSectionBGFirst').css({'height':($(window).height())-120+'px'});
}
$(window).resize(function(){
var windowH = $(window).height();
var wrapperH = $('.fullWidthSectionBG').height();
var newH = wrapperH + differenceH;
var truecontentH = $('.fullWidthSection').height();
if(windowH > truecontentH) {
$('.fullWidthSectionBG').css('height', (newH)+'px');
$('.fullWidthSectionBGFirst').css('height', (newH)-120+'px');
}
});
});
I am not sure I totally understand the effect you are going for here, but I would imagine that if your initial bit of code achieves it, all you have to do is reuse exactly that. Treat each resize as if the page had just loaded, and get the results you want, eg:
$(function(){
// encapsulate the code that we know WORKS
function init() {
var windowH = $(window).height();
if(windowH > wrapperH) {
$('.fullWidthSectionBG').css({'height':($(window).height())+'px'});
$('.fullWidthSectionBGFirst').css({'height':($(window).height())-120+'px'});
}
}
// call on page ready
init()
// ...and call again whenever the page is resized
$(window).resize(init)
});

$(window).height() doesn't update dynamically

I have this code for loading data. When user scrolls down over a half of screen, it continues to load data and append HTML to document. The problem is $(window).height() doesn't update on the fly after HTML changes so the condition expression goes wrong. How to fix it?
// Check scrollbar is down a half.
$(window).scroll(function() {
console.log("flag: " + flag);
console.log($(window).scrollTop());
console.log($(window).height());
if (($(window).scrollTop() > $(window).height() / 2)) {
if(flag == 0) {
console.log("Load data");
loadData(globalIndex, globalCount);
globalIndex += 40;
}
flag = 1;
} else {
flag = 0;
}
});
The height of your window isn't going to change unless you resize the browser screen. The problem with your formula is that in order to make it work, you'll need to load enough data to move your scrollbar back above the midpoint. If you don't, this formula will constantly return true, and you'll be calling loadData far more times than you care to.
As a potential workaround (depending on how long it takes to load your data), you can call loadData once your scrollbar reaches the bottom of your window. This condition will be true far less frequently than your current one, and it will only load data if your user is attempting to view it. If data loading is quick, then this is an easy solution. If it is a time-intensive process, and that's the reason you chose to load data once you got to the halfway point, then consider loading more data at a time and including a spinner or some other visual clue to inform the user that data is loading.
$(window).height()
will give you the browser's height (which is constant unless you resize your window). Try using:
$(document).height() - ($(window).height()/2);
instead...

Get Default Height Of Element On Webpage after css height has been applied)

How do I go about getting what the height of an element on a page would be if it ignored the 'height' css property applied to it?
The site I'm working on is http://www.wncba.co.uk/results and the actual script I've got so far is:
jQuery(document).ready(function($) {
document.origContentHeight = $("#auto-resize").outerHeight(true);
refreshContentSize(); //run initially
$(window).resize(function() { //run whenever window size changes
refreshContentSize();
});
});
function refreshContentSize()
{
var startPos = $("#auto-resize").position();
var topHeight = startPos.top;
var footerHeight = $("#footer").outerHeight(true);
var viewportHeight = $(window).height();
var spaceForContent = viewportHeight - footerHeight - topHeight;
if (spaceForContent <= document.origContentHeight)
{
var newHeight = document.origContentHeight;
}
else
{
var newHeight = spaceForContent;
}
$("#auto-resize").css('height', newHeight);
return;
}
[ http://www.wncba.co.uk/results/javascript/fill-page.js ]
What I'm trying to do is get the main page content to stretch to fill the window so that the green lines always flow all the way down the page and the 'Valid HTML5' and 'Designed By' messages are never above the bottom of the window. I don't want the footer to stick to the bottom. I just want it to stay there instead of moving up the page if there's not enough content to fill above to fill it. It also must adapt itself accordingly if the browser window size changes.
The script I've got so far works but there's a small issue that I want to fix with it. At the moment if the content on the page changes dynamically (resulting in the page becoming longer or shorter) the script won't detect this. The variable document.origContentHeight will remain set as the old height.
Is there a way of detecting the height of an element (e.g. #auto-resize in the example) and whether or not it has changed ignoring the height that has been set for it in css? I would then use this to update the variable document.origContentHeight and re-run the script.
Thanks.
I don't think there is a way to detect when an element size changed except using a plugin,
$(element).resize(function() //only works when element = window
but why don't you call refreshContentSize function on page changes dynamically?
Look at this jsFiddle DEMO, you will understand what I mean.
Or you can use Jquery-resize-plugin.
I've got it working. I had to rethink it a bit. The solution is on the live site.
The one think I'd like to change if possible is the
setInterval('refreshContentSize()', 500); // in case content size changes
Is there a way of detecting that the table row has changed size without chacking every 500ms. I tried (#content).resize(function() but couldn't to get it to work.

jQuery window scroll event. For every XX pixels scrolled

I am using the excellent jQuery Reel plugin (http://jquery.vostrel.cz/reel) for a project. I would like to bind to the window scroll event, so when the user scrolls down the page the plugin advances 1 frame for say every 10px scrolled, if the user scrolls up the animation is reversed.
The plugin has methods I can pass the values to no problem and I know how to bind to the window scroll event. What I am struggling with is the last.
How can I use jQuery/JavaScript to say for every 10 pixels scrolled in any vertical direction advance 1 frame in the animation? I know I can store the window scroll in a variable but I'm unsure how to say every time it hits a multiple of 10 advance one frame.
Many thanks in advance.
EDIT
Thanks to help of the users below I worked out a solution. As follows:
$(window).scroll(function()
{
windowScrollCount = $(this).scrollTop();
animationFrame = Math.round(windowScrollCount / 100);
});
So here I am getting the scrolled distance in windowScrollCount, translating it into frames in animationFrame and setting it back with .reel("frame", animationFrame); I am actually doing this for every 100 frames as every 10 was to quick.
Thanks to help of codef0rmer and noShowP I worked out a solution. As follows:
$(window).scroll(function()
{
windowScrollCount = $(this).scrollTop();
animationFrame = Math.round(windowScrollCount / 100);
});
So here I am getting the scrolled distance in windowScrollCount, translating it into frames in animationFrame and setting it back with .reel("frame", animationFrame); I am actually doing this for every 100 frames as every 10 was to quick.
If I'm wrong then you might want this:
var jump = 500; // consider this is your 10px
window.scrollHeight = 0;
$(window).scroll(function () {
console.log($(this).scrollTop());
var diff = $(this).scrollTop() - window.scrollHeight;
if (diff >= jump) {
window.scrollHeight = $(this).scrollTop();
console.log('reload frame');
}
});
Demo : http://jsfiddle.net/Dyd6h/
You could possible have a sticky element to the top of your page,
position: fixed; top 0; left: 0;
(hidden if you like).
And then when you are scrolling you can monitor its offset:
$('element').offset().top
You can then see how far down the page you have scrolled, so every time they scroll see what its top value is and trigger events appropiately?
EDIT:
I've set up a little JSfiddle with a start of what I think you need.
http://jsfiddle.net/qJhRz/3/
Im just calculating the frame you need to be on and storing that in a variable. Is it anything like what you're looking for?

Categories

Resources