I am running into some issues determining the type of browser using Javascript. My current method is to capture the screen width and height and determine the type of browser based on pixel sizes.
I figured I could assume that any screen width under 768 would be mobile, anything under 1024 tablet, and anything above that a desktop.
I've started testing on a few devices I can actually get my hands on and the results are much different. For instance on an android (Droid Bionic to be exact though it doesn't matter much) its returning a width of 980 regardless if the device is in landscape or portrait mode. This is much higher than I assumed.
Currently I am using document.documentElement.clientWidth to determine the width but I have tried other approaches such as window.innerWidth as well.
I guess what I am trying to get at is a question that has been asked many of times and I thought I had a pretty clear answer to. Apparently it might be time for a refresh on proper browser/device detection. So what is the most effective way to determine the actual size of the device I am on?
UPDATE:
It seems as if mobile browsers are actually taking it upon themselves to decide how to display my application. And in fact they are, but there is a way to stop it. See answer. Fortunately this means that the standard feature detection methods we are used to are still the best way to determine the device you are using.
Per Dagg Nabbit's comment on the question:
It seems that mobile browsers take it upon themselves to determine the way a site is displayed. This typically means taking a desktop version of a website and zooming out to fit the contents on the screen. For 90% of the internet this is necessary otherwise the mobile browsing experience would be horrifying. For responsive websites this is no good because in most cases we have very specific elements that must be altered depending on the resolution of the device the site is being viewed on. So how do we stop the browsers from doing this?
By using a viewport meta tag. The standard tag looks something like this:
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">
But there are a lot of different ways you can customize this to suit your needs. A good reference is https://developer.mozilla.org/en-US/docs/Mobile/Viewport_meta_tag
Related
I have an ASP.NET Web Forms Website that has css code to detect whether or not the screen width is less than 420 pixels. The client now wants this version (under 420 pixels) to function very differently than the full screen site, so I figured I could redirect to a mobile version of the website by detecting on the server side how wide the browser is. I am using 51Degrees to check Request.Browser.ScreenPixelsWidth, but that always returns the same value, even on my phone. Is there a better way to detect this information so that I can load a mobile version of my webpage?
If you want to get device-width, user-agent is not very helpful, because ultimately you need screen resolution and that will be the sole criteria to manage UI. So when more devices will come into market, you need to store their useragent and their dimension, this way, i am saying it is not helpful. And what if user has mobile or tablet, and changes orientation, means dimension just got changed for same user-agent.
So best way would be to go with css media queries to start with. There are lot of CSS to help you out for responsive design , such as bootstrap.
You're mixing two different technologies. For responsive design, you never need to use browser agent sniffing. Use a RWD CSS framework like Bootstrap. With RWD you serve the same content and functionality to ALL devices.
This really sounds like an argument to develop a separate mobile app if there's some part of it that need different functionality. Outside of that, the client is an idiot and it is frequently our job to educate the client ;-)
I want to accomplish something, and for that I need to know if the browser care about the meta viewport.
For example, chrome for iOS will be adjusted by the content of viewport. But chrome for windows won't.
What would be the best way to know if a browser uses the viewport content?
It looks like setting the viewport tag is up for a bit of debate. It sounds like your question might warrant ("Some visitors in my site don't care about responsive design") looking into the afore-tagged HTMLBOY blogpost; however, if you continue to use it, there are a few things to be aware of (the first, second, and third really being the take away points):
The website, itself, must be responsive - not just the browser, i.e. <meta... content="width=device-width"> won't do anything unless your website knows how to scale
It is true that the viewport tag is not currently a part of any web standard and was originally Apple-proprietary (this is the root, perhaps, of your problem). Not all browsers support it.
A pixel is not a pixel, i.e. a CSS pixel is not a physical pixel - the two are not tied together (this means that configuration attributes on the <meta> tag when related to the viewport can become problematic (particularly considering point no. 2, above, and elucidated in the linked MDN article in the same point). For further reading about the complications, you can read here and here
(helpful tip) If content on the website is important, don't set the maximum-scale or the user-scalable=no attributes. This will stop the user from examining important text more closely.
Now that all that is out of the way...
The answer to your question, "What would be the best way to know if a browser uses the viewport content?", is that there really is no great way to do it.
However, we do have two properties that can help us using in-line JavaScript that relate to the two concepts of the "visual viewport" (smaller) and the "layout viewport" (wider) thanks to the incompatibility between browsers "back in the day".
The visual viewport is the part the users sees on his or her screen - the part currently seen. This is what is scrolled when examining content larger than the device screen.
Everything related to CSS is calculated in relation to the layout viewport. As the linked article states, "How wide is the layout viewport? That differs from browser to browser."
Thus the element takes the width of the layout viewport
initially, and your CSS is interpreted as if the screen were
significantly wider than the phone screen. This makes sure that your
site’s layout behaves as it does on a desktop browser.
So, how can we leverage this to our advantage?
We can't detect if the browser supports the tag; however, we can detect if the browser has applied it. I'm not going to re-invent the wheel, so I'll link you to this SO answer and then an article which (already linked above) delves deeply into the topic. This knowledge should point you in the right direction.
I know this is an old question, but after trying all the proposed methods, nothing seems fit.
Basically, I built this webpage, it looks fine when just loaded with a mobile device, but after screen rotation the size stays the same, (which it should not!)
1:
The first method I tried is adding the meta tag:
<meta name="viewport" content="target-densitydpi=device-dpi, initial-scale=1.0, minimum-scale=1.0, maximum-scale=2.0, user-scalable=1" />
But apparently this does not work
2:
Then I tried window.location.reload
This works! Just perfect. But it basically reloaded the whole page, and all the previous setting will be reset to the default, this is not what I want!
3:
I see someone suggesting writing two sets of css, one for landscape and one for portrait. However, this is a lot of work right?
And, in my css I did not set a lot of explicit height and width anyway. Usually it's default, and sometimes in percentage. Is this a problem?
#
It will be great if someone explain a little what actually happens when the screen rotate? Why elements are not resized properly? And on contrary, why they will be resized properly if a reload event is triggered?
This depends on which mobile browser you're testing on; some mobile browsers, notably IE10, don't report a change in screen size when the orientation changes. However, as you found out the browser does recalculate the screen size when the page is refreshed.
If you can tell us about the browser, maybe we can help more?
I am having a issue when I try to make a web app responsive to screen-size.
I have css that I want to use for smartphones (iPhone, Andriod, blackberry, windows phone), and also have CSS I want to use for tablets.
My test devices are an iPad 3 (768 x 1024) and blackberry 10 (768 x 1280). and the widths being the same is an issue because my css starts with:
#media screen and (max-width:768px){
//enter code here`code here
}
Because the blackberry has slightly better resolution, it renders the CSS I don't want to use for it. Is there another way I'm suppose to check the media type? I was wondering if there is a way to check the width with a measurable distance (cm or in). not sure how to solve this.
thanks in advance
The “pixels” that are used in CSS declarations and when the browser reports the screen size of the client device have nothing to do with the actual real-world pixels on a device's screen. The “pixels” that are used in CSS are essentially an abstract construct created specifically for us web developers. To concern your self with the actual amount of real-world pixels on a high-resolution mobile screen is, for most web applications, completely unnecessary and will only lead you to utter madness.
You can determine the browser and device type by inspecting the navigator.userAgent property in JavaScript. For example, to test for (practically) any mobile device:
// if mobile === true, 99% chance the device is mobile.
var mobile = (/iphone|ipad|ipod|android|blackberry|mini|windows\sce|palm/i.test(navigator.userAgent.toLowerCase()));
You can of course inspect navigator.userAgent to determine if the user is on a specific type of device or browser that you are particularly concerned about or having a problem with.
But again, in my personal experience, clever, simple, and flexible responsive CSS design (supported by media queries and JavaScript, too, of course) will render beautifully on 99% of device/browser combinations without having to resort to inspecting navigator.userAgent to create different styles for individual devices.
You can also restrict your styles to the height:
#media screen and (max-width:768px) and (max-height:1024px){
// iPAD
}
You should add the meta tag viewport in your html header :
<meta name="viewport" content="width=device-width, initial-scale=1">
To sum up :
width = device width x pixel density
(Galaxy S4 : 1080 = 360 x 3)
This metatag allow you to catch the device width instead of the "faked width" (360 instead of 1080)
Some good reading :
https://developer.mozilla.org/en-US/docs/Mozilla/Mobile/Viewport_meta_tag
http://screensiz.es/phone
http://www.html5rocks.com/en/mobile/mobifying/#toc-meta
This sounds a bit too good to be true, so please tell me if it is.
If I have just one single version of a mobile website (no variations for
different devices, just one website for all mobiles), how reliable it is
to detect mobile devices by screen resolution?
And simply serve the mobile version if screen resolution is < than say 400px.
NOTE: My question assumes that javascript is enabled. Also,I'm aware there's
user agent detection, but I'd like to do without it.
Javascript mobile device screen detection for height is not reliable at all. The problem is that different browsers use different amounts of 'chrome' and different OS versions use different heights for the system bar. All the detection mechanism report unreliably for height (screen.height, window.outerHeight, window.innerHeight - etc,etc)
Width seems to be most reliable on window.outerWidth across all OS's.
Read a most excellent analytical report here:
http://www.tripleodeon.com/2011/12/first-understand-your-screen/
You will want to look into serving different stylesheets via media queries. You can use queries to identify screen widths and only serve certain css to certain devices. For example this query would serve a iphone.css only to devices identified as having the typical dimensions of an iphone:
<link media="only screen and (max-device-width: 480px)" href="iphone.css" type="text/css" rel="stylesheet" />
There's a detailed article on this subject over at alistapart
Bear in mind though that not all devices recognize media queries. If you need to support lots of older devices like blackberry's and flip phones you should take the advise above for using UA detection - I know it feels wrong if you're coming from the desktop development world but really we have to use the tools we have available to us and Mobile Web is a growing but in many ways still a new horizon.
I came here because I had the same idea and question, and similar situation - the website already requires JavaScript and I'm doing a one-size-fits-all mobile web app, at least for now. Our release cycle is really long - any UA detection I hard-code will be somewhat obsolete by the time the code is tested and released. Since the purpose of this alternate interface is to make it work on smaller screens, it would seem to make sense to use that test.
I don't know however, what size I would pick - I have a hunch mobile devices are not bound (even by convention) to particular screen dimensions. I guess we just have to decide at what point the main web page is no longer functional.
I can understand other people's hesitation to this approach because sometimes there are other issues with a standard site on a mobile device than just the screen size. However, I think there is an advantage to this kind of detection. If your only issue is the screen size, I think it is a good way to go.
Probably not going to hurt to add this functionality to your website for those who are indeed running JavaScript enabled web browsers on their mobile devices. As for those who are not, well there's little you can do about them, other than something simple like letting them select their screen size at first load? Maybe a simple drop down list with possible sizes?
It depends on what you want to achieve.
If you design for different screen resolutions regardless of device type then it is fine to use resolution ranges.
If you design for specific device types (phone, tablet, etc.) and assume a resolution range will always match a single device type, then it will eventually break.
You used a 400px threshold in your example, the Galaxy S8+ reports 412x846 with this code:
console.log("width: " + screen.width + ", height: " + screen.height);
Device resolutions change every year and they are starting to overlap with each other. Large phones have higher resolutions than small tablets and large tablets have higher resolution than some desktops.
You may get away with it if you just want it to mostly work or if you want to detect specific phones.
However it is not reliable to use screen resolution alone to detect the device type.