Difference between revisions of "Responsive design"
(→Grid) |
|||
Line 190: | Line 190: | ||
Elements can be position in grid, using the division: where/how-many-division; Like for instance: | Elements can be position in grid, using the division: where/how-many-division; Like for instance: | ||
<source lang="css"> | <source lang="css"> | ||
grid-column: 1 / 3; | |||
grid-row: 1 / 4; | |||
</source> | </source> | ||
Line 200: | Line 200: | ||
} | } | ||
</source> | </source> | ||
==Grid align-items== | ==Grid align-items== |
Revision as of 12:04, 28 October 2019
A simple approach that lets you build a single site that adapts to different device widths
RWD: 3 basic techniques
percentage-based/flexible grids: you skip fixed-width layouts.
Since smartphone screens come in a wide variety of widths, it makes no sense to create a page at a fixed width; instead, you want the page to grow or shrink to fit the particular device
media queries:
CSS technology that lets you send different styles to a browser based on current conditions in the browser.
flexible media:
lets your images and videos scale to fit the appropriate screen real estate…big photos for big monitors, smaller photos for small screens
References
Sawyer MacFarland. 2015. "CSS: The Missing Manual". 4th edition link
Interneting is Hard on Responsive Design
Setting Up a Web Page for RWD
meta tag: no zoom out
Phone browsers: don’t just display the page at 100 percent. Instead, phone browsers zoom out to fit the page on screen.
The exact amount they zoom out varies from phone to phone. Safari on the iPhone, for example, acts like the screen is really 980 pixels wide, so it shrinks the page down to fit within 980 pixels.
This behavior of mobile browsers works well for the majority of sites, but not so well with a responsive web design. Because responsive sites are intended to look good on phones, you don’t want the display to zoom out.
there’s a simple way to override this behavior of mobile browsers.
Simply add the following code to the <head>
<meta name="viewport" content="width=device-width">
HTML meta tags provide extra information about the page’s content and can give browsers extra instructions about how to display the page. In this case, the viewport refers to the browser screen, and the content attribute sets the width of the browser to the width of the phone
Media queries
RWD tries to give your site’s visitors the most readable and attractive presentation possible. This usually means customizing the design to look its best at different browser widths.
Many designers think of three target screens related to the three most common web browsing devices: smartphones, tablets, and desktop computers.
Strategies for Using Media Queries
Media queries, which let you assign styles to a page based on the destination browser’s width and height.
3 target screens: * smart phone * tablet * laptop/desktop computers
Strategies:
Adjust columns:
Multiple side-by-side columns look great on a big monitor (and even on a tablet in landscape mode), but not so much on a phone. Bringing the page down to 2 or 3 columns
Liquid design:
widths of your content divs to auto
or 100%
. This setting converts your page from a fixed-width design to a liquid, or flexible, design, that constantly adjusts itself to the size and orientation of the screen. However you can still use fixed-width for a desktop browser, such as setting the width of div to 900px, but a phone is unlikely to have that width, which means great part of the div will be off-screen.
Tighten up white space:
in large screen ample space between content is desirable, but on small screens results into elements being rendered too far apart, like islands of content. Reduce padding
and margin
.
Less contrasting font sizes:
differences between large size of headings and small body text, must be more moderate
long menus will break or disappear in small screens. CSS doesn't provide a good solution for this. The effective solution is to use JavaScript to dynamically change the navigation menu into an HTML drop-down menu (A Google search on "responsive menu js library" will yield douzens of possible options).
Hide content for mobile:
Too much information on a phone can be overwhelming. You can use CSS to hide content that you think is superfluous for mobile users by setting the CSS display
property to none
.
Use background images:
A large image on a phone will be hard to display fully and take a long time to display. To avoid this problem create 2 versions of the same image a large and smaller (for mobile). In the CSS, if you place the image as background of a div, you can change that images, in 2 style sheet one for desktop another for mobile.
/* Extra Small Devices, Phones */ @media only screen and (min-width : 480px) { .logo { // liquid design width: 100%; height: 60px; background-image: url(images/small_logo.png) } } /* Small Devices, Tablets */ @media only screen and (min-width : 768px) { .logo { // liquid design width: 100%; height: 60px; background-image: url(images/small_logo.png) } } /* Medium Devices, Desktops */ @media only screen and (min-width : 992px) { .logo { // fixed design width: 960px; height: 120px; background-image: url(images/large_logo.png) } }
Mediaquery breakpoints
Breakpoints used by [Bootstrap](https://v4-alpha.getbootstrap.com/layout/overview/#responsive-breakpoints)
/* Extra Small Devices, Phones */ @media only screen and (min-width : 480px) { } /* Small Devices, Tablets */ @media only screen and (min-width : 768px) { } /* Medium Devices, Desktops */ @media only screen and (min-width : 992px) { }
CSS media queries can do more than just check the width of a browser. The current media query standard states that you can check for height, orientation (whether a visitor holds a mobile phone in portrait or landscape mode), and even whether a device uses a color or monochrome screen. There are a few other browser characteristics you can check with media queries, but not all browsers support the queries. For more on media queries see https://developer.mozilla.org/en-US/docs/Web/CSS/@media#Syntax.
From default design to media-queries
Don’t need to create three separate sets of styles.
You can start with a default design; that is, a design that works without media queries, for either mobile or desktop, choose what approach you prefer.
Then create media-query styles to override the default styles and reformat the page for the particular screen width.
To main approaches:Desktop or Mobile first?
Desktop first
Design your site with the desktop in mind. Throw in all the columns you want. Polish and finalize the design so it looks great on a large monitor. This becomes your base CSS design.
This becomes the base, the default.
Then you add media queries for tablets and phones, which tweak the base desktop design, by removing columns, making headline text smaller, reducing borders and padding, etc.
Mobile first:
its the inverse of Desktop first. You designing first for mobile browsers.
The basic small-screen styles is the default CSS.
From it, make adjustments inside media queries for tablets and desktops, by adding columns larger headings, padding & border, showing more content.
Grid
CSS Grid Layout divides a page into major regions.
Like tables, grid layout enables an author to align elements into columns and rows. However grids is far more flexible than tables. For example, a grid container's child elements could position themselves so they actually overlap and layer, similar to CSS positioned elements.
Grid Basic
The Grid, is a two-dimensional layout model to organize items, in rows and columns
To create a grid add the following to the the container:
display: grid;
grid-template-columns: repeat(3, 1fr);
how many columnsgrid-template-rows: repeat(5, 1fr);
how many rows (optional)grid-gap: 10px;
the space between grid cells
Grid divisions
grid-auto-rows: minmax(100px, auto);
defines the minimum height of the rowsgrid-auto-columns: minmax(auto, 200px);
defines the maximum width of the columns
But to be more precise we can determine how we want the grip to be divided
grid-template-columns: repeat(3, 1fr);
divided into 3 columns with flex factor of 1grid-template-rows:repeat(auto);
divided into as many rows as necessary
Element positions in Grid
Elements can be position in grid, using the division: where/how-many-division; Like for instance:
grid-column: 1 / 3;
grid-row: 1 / 4;
.container div:nth-of-type(1){ background:#ddf4504f;
grid-column: 1 / 3;
grid-row: 1 / 4;
}
Grid align-items
align-items:
Controls where the flex items, with different sizes sit, vertically, in relation to one another.
Possible values:
- stretch (default)
- center
- flex-end
- flex-start
Reactive Grid
What if we want to go from a multi-column grid, to a single column layout on small screens?
Rather than specifying the grid-template-columns with a fixed number of collumns, we can keep it as auto-fill and say we want each column to be a minimum of XYZ.px
So that when the width of the columns in a 2, 3, 4 column layout become smaller than XYZ.px it will move 1 column to a row
grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
See example: https://codepen.io/PublicationStation/pen/OJJjMyg
Grid Links
Flexible grids create a liquid layout, in which the page’s overall width resizes to fit different width screens.
In most cases implementing a flexible grid, can be created by setting the:
- parent container box (div):
width
to100%
.max-width
to a certain amount of pixels, so that the page isn’t absurdly wide on large desktop monitors.
- Individual columns
width
: percentage-based
Flexbox
Flexbox Intro
The flexbox, is a one-dimensional layout model to organize items, in one dimension, either as a row or as a column. (For 2 dimension layout check the property display: grid
)
Based on: https://developer.mozilla.org/en-US/docs/Learn/CSS/CSS_layout/Flexbox
Flexbox Basics
Follow the example in https://codepen.io/PublicationStation/pen/NWWgovQ
Flexbox works with a set of items in a container, where the container has
display: flex
- container: groups flex items together and define how they’re positioned.
- flex items: main purpose are to let their container know how many things it needs to position. Flex items can be manipulated individually, but for the most part, it’s up to the container to determine their layout.
We can indicate if we want to organize the items as rows or columns; with
flex-direction: column;
or flex-direction: row;
Note however that when setting flex-direction: row;
- all items will appear in 1 row.
- all items will be resized to fit the screen width.
To have more control over how many items appear in 1 row and the width of each item, we can:
- let the flex items wrap onto multiple row
flex-wrap: wrap;
flex-wrap: no-wrap;
will force them onto a single row.
- set a minimum with for each item
flex: 300px ;
Flexbox align-items
https://developer.mozilla.org/en-US/docs/Web/CSS/align-items
align-items:
Controls where the flex items, with different sizes sit, vertically, in relation to one another.
commons values:
- stretch
- center
- start
- end
Flexbox other options
flex-basis:
specifies the initial main size of a flex item.
order:
to changes the order of individual elements
Flexbox tutorials
- https://css-tricks.com/snippets/css/a-guide-to-flexbox/
- https://developer.mozilla.org/en-US/docs/Learn/CSS/CSS_layout/Flexbox
- https://scotch.io/tutorials/a-visual-guide-to-css3-flexbox-properties
Fluid images
In addition to placing images as background, as suggested in before Strategies for Using Media Queries, it is also possible to set fluid <img>
by placing the image inside a div and making its max-width: 100%
. Without any other width or height instructions. The image will resize as its parent div resizes.