How to make responsive web page render faster? - javascript

Right now, every time I try to render a page, I will calculate the $(window).width() first and then add a corresponding class for the root html element, which will final determine the block width of some main responsive elements in the page. But this approach goes with a problem. It will first render the page with a initial default width, and then after the class is added, it will adjust the element width, which will create a non-smooth visual effect.
To overcome this, I then make all the responsive elements display: none in the first place and make them visible after the width calculation is done. But for a user, it takes more time to see the page in this way.
So I was wondering if there is a way to achieve this responsive page in a more efficient and faster way?

If you are using javascript to create a responsive site, there are much easier ways.
For example, there are TONS of free CSS based frameworks you can utilize to make responsive pages that the CSS controls, which doesn't eat up nearly as many resources as a javascript solution. Lots of DOM manipulation with javascript can get pretty hairy pretty quickly.
My suggestion would be to look into some of the following:
Foundation: http://foundation.zurb.com/index.html
Skeleton: http://www.getskeleton.com/
I personally use foundation for my development, as its easy to read/understand and it produces rapid development.
Example: http://www.sinsysonline.com/secondhomehostel
If you are ABSOLUTELY dead set on having Javascript handle your DOM rendering, it's going to be much slower than a CSS responsive site.
If so, try out:
Response JS: http://responsejs.com/
If you would like further clarification for a specific problem, could you please provide your code and I'm more than happy to provide some feedback on that.

CSS media queries allow you to apply CSS based on screen size. The advantages of this over your approach are:
1) The CSS will read the window size immediately
2) The page will automatically adjust if the user resizes the window (or rotates their tablet)
https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Media_queries

You need to use css3 media queries which is very useful to create responsive website. You need to write css according to viewport width. Please refer the link from which you will get all the idea about responsive website.
I hope this will help yo to work on the responsive websites.

Related

Make Element Full Height of Page on Bubble.is

How can I make an element the full height of a page on the website editor of bubble.is. So, when opening the page on differently sized computer screens, my element would always cover the full height of the page. An example of this effect is https://kickpoint.ca/contact/
I’m thinking I may need to use html or JavaScript to do it, but I’m not sure how and if there’s a simpler solution.
Thank you
What you actually want for this is css. I would read through a quick tutorial. I am not familar with Bubble.is, however css is for styling webpages. After a simple tutorial you will know exactly how to do what you are trying to do. It would be something like #element-id{ height: 100%}. or on the html element:

Using Enquire for layout as opposed to using CSS for layout

I am aware of the fact that layout and function of a site should be strictly separated. Layout should be done with CSS and functions of the site, like expand mobile menu on click, should be done with JS.
Reference:1. & 2.
What I often see happening for responsive layouts is having column classes for the various media queries, where just the class name is different, however the width values are identical.
This then leads to HTML in the form of
<div class="container small-query-columns-4 medium-query-columns-6 large-query-columns-12><p>Responsive paragraph..</p></div>.
Would it be acceptable to instead of always defining the same width for columns for various media queries to just make a minimal CSS grid, where the column classes widths are defined once and then dynamically pass those per media query with Enquire?
I know this ruins the above given separation from layout (CSS) and function (JS), though it would mean much cleaner HTML, and this per each media query plus much less CSS as well. Enquire also only calls once per media query so the hit on the amount to download would also be much less with a minimal CSS file. Yes, of course, this means the site is JS depended.
That's not bad idea but I think that it is not good idea too. I had thought about something similar few weeks ago. I wanted to make CSS which will be compiled in browser via JS in few loops and then appended to head section. But after deep thinking I decided to not doing that.
I know that you can make fallbacks and some fancy stuff so it works in every browser with or without js, but I have looked at my grid. It takes less than 10KB. It's interesting idea, but it isn't worh so much work as it will take. Keep your HTML organised and you won't run into issue with too many css classes. You have to let someone who use your "framework" do define widths at certain breakpoints. Easiest thing to do is just write a class name.
Consider that when you use for example bootstrap and want to have 12 columns on mobile, you just don't define it and it automatically falls into that width. Many times it just enough to define max 2 breakpoints with css classes.
When I think about enquirejs I think that it can be used for hiding sliders on mobile for example. When you just display: none it still running and changing classes. If you have something similiar what should be removed because mobile is not good environment for running something, you can disable it by using enquire. Another example is mansory grid, which you can start and disable via enquirejs.
Basically you can use it if you have something already js-depended and want to customize it on diffrent screens, or give diffrent behavior, because if you just set something on window load or document load, you have an issue with someone who resizes window. Here you can use it.

Best JavaScript library for animating multiple divs

I have a grid of div boxes that I will be animating. They will be moving across the screen after a user drags one of the boxes (to re-align into a grid).
Currently I am using JQuery to change the css left and top positions of all of the divs and running this on an interval.
It is laggy if there are more than 50 boxes. How do I make this less laggy? Is there an animation library that is better for this, or do I just need to limit it to 50 boxes?
Image of layout:
You have a few options to optimize the performance.
Newer browsers have requestAnimationFrame that lets the browser take care of the animation timing in order to optimize Javascript animations. Rather than using times to perform the animation, which is what jQuery framework uses, you repeatedly a callback to requestAnimationFrame. The browser will call your function with a progress variable for the animation, and you render the current stage of your animation based on the progress variable. requestAnimationFrame for smarting animating talks about this in depth. Google Closure is the only framework I am aware of that uses requestAnimationFrame however, and it's rather heavyweight.
CSS animations. jQuery offers CSS animation, so do many other frameworks. CSS animations give you hardware acceleration, so the animation is much faster. Unfortunately, CSS animations are relatively new and not yet well supported, so you'll probably end up falling back to Javascript animation on older browsers, depending on the library you use.
Optimize your Javascript. Instead of animation each and every box in the grid, encapsulate each row in a div and animate the entire div instead. That should speed the animation up by a bit. I'm sure there are other ways you can optimize based on your current implementation.
Honestly, I don't know of any library that will make this work more efficiently for you, though there are many libraries out there that are faster than jQuery. The issue isn't just the jQuery, its the fact that you have 50 elements that are all moving/draggable, thus requiring a lot of the browser's resources.
If you can post your code there may be a few things that we could suggest to speed it up slightly.
The two biggest things problems that I can think of are if you added those boxes programmatically and added the handler for each as you added the element to the page, and if you don't store your selectors in variables. Aside from that I would have to see the code.
Have a look at:
jQuery isotope
It has options to allow you to use css3 animations if available or use jQuery / JS animations.
Handy for grid like animation and arrangements.
Some brave soul has managed to add drag and drop to isotope too. http://tyler-designs.com/masonry-ui/ (a bit clunky but works)
There are several ways of increasing the performance. One would be to reduce the amount of DOM elements required for each box. Another is to not animate (and render) boxes outside of the current viewport. Give all boxes that are outside of the viewable area "display: none;" and exclude them before starting a new animation. If you want to go even further you can start to recycle boxes instead of showing and hiding them when the user is scrolling through the page.
This way you will always get the same performance no matter how many boxes you have (above the amount that you can fit in the viewport).
This technique is called UI virtualization. There are several projects that use it like: http://github.com/mleibman/SlickGrid/wiki. It's really useful when you need to render a lot of elements (hundreds, thousands, millions). But it takes quite some work to get it right. And I don't know about any generic working components that are easy to plug in. I tried to find an article that explains it. This is the only thing I could come up with for now, it's for Silverlight though: http://www.silverlightshow.net/items/Virtualization-in-Silverlight-4-RC.aspx
Also try this this plugin for jQuery. Use the regular 'animate' method and it will try to use (hardware accelerated) CSS animations where possible: http://playground.benbarnett.net/jquery-animate-enhanced/

Blur all the objects(Images,div,text..) that comes behind a div tag

Need your help.
I created a static semi-opaque banner which stays at the top of a website. When a user scrolls the website the entire container objects goes underneath the banner. I want all the objects (images, text..etc) getting blury effect as it goes underneath the banner.
Thanks
The only way you're going to be able to do this is by getting fancy with some CSS and javascript. CSS doesn't support blur directly, but you can emulate it with text-shadow. Images can also be blurred with a little jquery/css/javascript magic, but will be problematic because you can't partially blur an image (what happens when only part of the image is under the banner?). It could probably be done by layering your images and keeping track of their position on screen, but all of this seems like a lot of work for a very small return.
So, assuming you've decided to give all of this a shot, you're going to have to use javascript to determine which parts of the page have passed under the banner and apply the style to those parts. The difficulty of this task will scale with the complexity of your page layout. In a best case scenario, your banner and content container are both 100% the width of the html body. At this point, it would be fairly trivial to write some kind of scanner that traverses the dom every time you page scroll to find elements that the blur should be applied to. However, best-case-scenario is rarely the case at hand, at which point I'd recommend abandoning the effort to pursue something with a greater ROI.
This isn't possible with CSS nor jQuery. You might be able to do something with IE's filters, however that's IE only (of course), and will invalidate your CSS.
Currently, there is no way to do this, although something might come along in CSS 4 or something.
The Chrome nightly builds support some filters, however there isn't an alpha blur filter (yet, at least).

Change CSS depending on page width javascript?

We're working on a web app that will deployed to mobile devices, iPad, iPhone, Android. Instead of trying to filter out user agents to display different views, I'd much rather just have my CSS change depending on the width of the screen (that's the only important thing here, really)
We've got something put together with jQuery, and I've changed the CSS for one part so that when the width shrinks, it doesn't take up too much vertical space (shown below)
How would I go about implementing something like that on buttons like this:
Ideally I should be able to change the CSS or something similar so the buttons are stacked up all in a row if width is narrow enough to knock even one button off. After that I can work on making the buttons look correct.
The simplest way to change CSS depending on the page width is to use Media Queries, which require no JavaScript.
Here's a great intro to Responsive Web Design from the guy who's considered the originator of the concept:
http://www.alistapart.com/articles/responsive-web-design/
If you want to actually change page content based on page width, you'll need something like RESS. Here's a simple script for that, but it requires cookies and doesn't adjust on screen resize, so unless you absolutely require it, media queries are a much better.

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