In my app I use Bootstrap and I set 2rem to my h2 element and 1.7rem to my h3 tag. Even if I adjust the browser width in my desktop (to the size of a mobile) the h1 is bigger than h3 which is what I want. But if I use the developer tools to switch to a mobile device view or view the site from my phone the h1 becomes smaller than the h3! What might be happening in here? It happened in multiple sites I created.
Example fiddle (Could not replicate the issue in the fiddle. But it's the code) : https://jsfiddle.net/gor87kg6/1/
The live site which have the issue : http://jayatours.lk/
Following the Bootstrap mobile first approach I noticed your website was not utilising the viewport meta.
Try adding the following to the <head>:
<meta name="viewport" content="width=device-width, initial-scale=1">
Background Information:
Mobile browsers render pages in a virtual "window" (the viewport), usually wider than the screen, so they don't need to squeeze every page layout into a tiny window (which would break many non-mobile-optimized sites). Users can pan and zoom to see different areas of the page.
Viewport Information:
The width property controls the size of the viewport. It can be set to a specific number of pixels like width=600 or to the special value device-width value which is the width of the screen in CSS pixels at a scale of 100%. (There are corresponding height and device-height values, which may be useful for pages with elements that change size or position based on the viewport height.)
I believe this may be the cause of your issue as the use of rem seems to be correctly implemented. It might be more likely down to the dpi/ screen resolution of the mobile/ tablet device itself.
rem is a unit relative to the font size of the base (html) tag. The default in browsers is usually 16px if you haven't explicitly declared it. Perhaps the mobile browser has a smaller default?
Try setting the base font size before using rem units:
html { font-size: 16px; }
I don't see any issue. If you still see the issue then there could be 2 ways to resolve this:
1) See that the h1 font-size is not being set again in the media query
2) Check the base font applied to the html & whether it is being reset in the media query
Related
This is a test page mentioned in Google web dev responsive design article for testing the viewport meta tag:
https://with-vp-meta.glitch.me/
There is a strange behavior observed when testing with chrome dev tools responsive devices in devices with very low width (at least below 320px)
If you keep on reducing the width, there comes a point where the html body width is not equal to the device pixel width anymore (though it should be equal as per the width=device-width value).
It looks like this:
As you can see, the body tag is selected in the Elements panel. The size of the selection is much less than the 81px device width as mentioned in the dev tools device header (81 x 711)
If you look at the dimensions in computed styles: the dimensions are mentioned as 81px width
This is a real issue, actually happening with my website (on not so smaller width), and this is just an example to recreate it easily.
I suspect this has something to do with the viewport meta tag and it's handling, but i am not able to pinpoint what the problem is. I have tried different combinations of width and initial-scale to recreate this scenario in other dimensions, but wasn't able to recreate a scenario where the rendered body width is less than the viewport width, but devtools inspect still shows the dimensions as correct, although the rendered dimensions do not match the pixel dimensions?
I am using the following viewport meta in my html:
meta name="viewport" content="width=device-width, initial-scale=1
Which works perfectly for mobile devices. However, on the desktop version all assets, fonts and even the various elements are increased in size by 20%.
For example, see the image below. Even though the image is defined as being 300px by 300px in the devtools, if I take a screenshot and measure it in Photoshop it is in fact 360px by 360px.
The browser zoom is at 100%. What am I doing wrong?
/** EDIT **/
So, I found out that Windows sets the size of images and text to a default of 125%. That is why my website images and text were looking bigger. Now that I can see that is the case, how can I find a workaround so that even with the setting at 125% the images and text will display as intended? Is it even possible?
The problem is that a CSS px is not equal to a physical pixel. The definition is complicated, but in desktop browsers, the ratio between a CSS px and a physical pixel (A.K.A devicePixelRatio) is equal to the OS display scaling factor.
This is done in order to adapt to various screen resolutions and their distance to the observer. In my screen, the image in the codepen you sent is 600x600 physical pixels, because my screen is high PPI. I would have difficulty seeing text rendered with the default size in pixels.
If you really need to set the dimensions in physical pixels, you can just divide each dimension by `devicePixelRatio, but that creates accessibility concerns.
I worked it out in the end. In jQuery you can add the following to make your website display as intended:
$(document).ready(function(){
checkBrowserDpi();
}
function checkBrowserDpi(){
if(window.devicePixelRatio == 1.25 ) {
$("header, section, footer").removeClass("zoom100");
$("header, section, footer").addClass("zoom080");
} else {
$("header, section, footer").removeClass("zoom080");
$("header, section, footer").addClass("zoom100");
}
}
$(window).on('resize', function(){
checkBrowserDpi();
});
and then have two classes in your CSS file as follows:
.zoom100 { zoom: 100%; }
.zoom080 { zoom: 80%; }
In this particular case, it checks the device pixel ratio when the document is loaded and every time the window is resized and then sets the correct zoom to the header, section tags and footer for desktop browsers. You set the zoom to any tag you wish.
** EDIT **
As #D.Pardal points out this does create accessibility issues which I had not taken into consideration. That said, if you do want to mess with the devicePixelRatio then the method above works.
Is it mandatory for responsive design the use of the meta tag viewport?
<meta name="viewport" content="width=device-width,initial-scale=1">
I have done few test without and it works well on desktops browser and it adapts propertly to the size of the windows, even if I use viewports as width or height to define header and footer.
So is that meta tag only useful to mobile devices or that's either necessary?
Does viewport use a default width or height for mobile devices?
When the meta tag is not defined there is a virtual viewport default values defined. Non-mobile-optimized sites with these default vaules looks in general better on narrow screen devices.
On Safari iOS the default width is 980 pixels, and the others browsers width size are alike or a little less.
Narrow screen devices (e.g. mobiles) render pages in a virtual window or viewport, which is usually wider than the screen, and then shrink the rendered result down so it can all be seen at once. Users can then pan and zoom to see different areas of the page.
For example, if a mobile screen has a width of 640px, pages might be rendered with a virtual viewport of 980px, and then it will be shrunk down to fit into the 640px space.
Explanation and default values for width and height with viewport on mobiles
Apple as the inventor of viewport says that the default viewport settings are:
The default width is 980 pixels. However, these defaults may not work well for your webpages, particularly if you are tailoring your website for a particular device.
Apple configuring viewport and default values
This is the common setting of viewport used in various mobile-optimized websites. The width property governs the size of the viewport. It is possible to set it to a specific value (“width=600”) in terms of CSS pixels. Here it is set to a special value(“width= device-width”) which is the width of the device in terms of CSS pixels at a scale of 100%. The initial-scale property governs the zoom level when the page is loaded for the first time.
Note: The meta tag should be added in the head tag in HTML document.
A Responsive tags has the following attributed:
width: Width of the virtual viewport of the device.
height: Height of the virtual viewport of the device.
initial-scale: Zoom level when the page is first visited.
minimum-scale: Minimum zoom level to which a user can zoom the page.
maximum-scale: Maximum zoom level to which a user can zoom the page.
user-scalable: Flag which allows the device to zoom in or out.(value= yes/no).
Ref: https://www.geeksforgeeks.org/html-viewport-meta-tag-for-responsive-web-design/
Demo
I want to make responsiveness behaviour like at this site.
There is meta viewport content set to width=device-width, initial-scale=1, maximum-scale=1, but if i resize browser vieport size by reducing its width (about 200px width and smaller), content scales proportionally and responsiveness "swithes off".
You can compare this site and jsFiddle demo with picture below. The same text with the same font-size, but scales differently.
UPD
I need to know how can i set 20px font size and it will scale proportionally like without using meta viewport. Try to make a <h1> with meta viewport and without one, you will understand what i mean
Your question is unclear, but assuming you're talking about the fact that on your demo, the content is blocking its resize after a certain minimum width:
It is important to understand the function of the meta viewport.
The viewport is the user's visible area of a web page.
The viewport varies with the device, and will be smaller on a mobile phone than on a computer screen.
-Source
This function prevents a user to zoom in or out on your website. The code you give us says that the width of your webpage must be the width of the parent viewport (equal to your browser's viewable area), that the initial zoom has to be 1 (that means no initial zoom is set) and that the maximum scale can be 1 (that means no zooming in allowed).
The fact that your website is responsive until a certain minimum width hasn't any direct link to the meta viewport.
The responsiveness of a website is based on what's called breakpoints in CSS. This gives certain CSS rules based on the viewport properties (in responsive cases: if the screen's width is between a certain minimum amount of px and a maximum amount). According to what I can understand, you actually need to set the CSS min-width attribute to your website's body like this:
body {
min-width: 300px; /*You'll have to set the value you wish here*/
}
The next thing you have to do is choose how you will handle screens smaller than 300px. There are two options after this:
You can choose to force-give your webpage the device's width and prevent horizontal scrolling but this will hide all the overflow. I personally suggest not to use this technique. For doing this, you'll need to hide all html's overflow with this CSS: html {max-width: 100vw; overflow-X: hidden;}.
The other (better) option is to give your webpage the minimum required width. This will allow horizontal scrolling and a better user experience. To do so, use this CSS code: html {min-width: 300px; overflow-X: visible;} (remember to replace 300px with your desired minimum width).
This should be all for now. Remember that there are hundreds of guides for responsive web design available. Hope your issue is solved.
The solution was simple. I needed just set body min-width
I'm making my website responsive and have started development with the mobile half first.
Browsers render sizes so differently, especially mobile ones.. So all my font sizes aren't set, and the browsers set it themselves. It works great, even the default on an old blackberry.
Problem is, the content of list items within an unordered list doesn't resize.? They stay very small next to the perfectly adjusted text outside <ul>'s
I've tried using em as my measurement unit, and not only did this not work, it also defeats the point of me making my site dynamic to any browser; I don't want to set a size on anything, especially fonts.
So what can I do to make the font size adjust inside the lists?
In mobile broswer, you'd better set test-size-adjust to none,
body{-webkit-text-size-adjust:none;}
After reset test-size-adjust to none, then try to set other html tags' font-size.
<meta name="viewport" content="width=device-width, user-scalable=yes" />
I came across this tag on another question; it works perfectly.