Archiwum kategorii: CSS

Should I Use Source Maps in Production?

Post pobrano z: Should I Use Source Maps in Production?

It’s a valid question. A „source map” is a special file that connects a minified/uglified version of an asset (CSS or JavaScript) to the original authored version. Say you’ve got a filed called _header.scss that gets imported into global.scss which is compiled to global.css. That final CSS file is what gets loaded in the browser, so for example, when you inspect an element in DevTools, it might tell you that the <nav> is display: flex; because it says so on line 387 in global.css.

On line 528 of page.css</, we can find out that <code>.meta has position: relative;

But because that final CSS file is probably minified (all whitespace removed), DevTools is likely to tell us that we’ll find the declaration we’re looking for on line 1! Unfortunate, and not helpful for development.

That’s where source maps come in. Like I said up top, source maps are special files that connect that final output file the browser is actually using with the authored files that you actually work with and write code in on your file system.

Typically, source maps are a configuration option from the preprocessor. Here’s Babel’s options. I believe that with Sass, you don’t even have to pass a flag for it in the command or anything because it produces source maps by default.

So, these source maps are for developers. They are particularly useful for you and your team because they help tremendously for debugging issues as well as day-to-day work. I’m sure I make use of them just about every day. I’d say in general, they are used for local development. You might even .gitignore them or skip them in a deployment process in order to serve and store fewer assets to production. But there’s been some recent chatter about making sure they go to production as well.

David Heinemeier Hansson:

But source maps have long been seen merely as a local development tool. Not something you ship to production, although people have also been doing that, such that live debugging would be easier. That in itself is a great reason to ship source maps. […]

Additional, Rails 6 just committed to shipping source maps by default in production, also thanks to Webpack. You’ll be able to turn that feature off, but I hope you won’t. The web is a better place when we allow others to learn from our work.

Check out that issue thread for more interesting conversation about shipping source maps to production. The benefits boil down to these two things:

  1. It might help you track down bugs in production more easily
  2. It helps other people learn from your website more easily

Both are cool. Personally, I’d be opposed to shipping performance-optimized code for learning purposes alone. I wrote about that last year:

I don’t want my source to be human-readable, not for protective reasons, but because I care about web performance more. I want my website to arrive at light speed on a tiny spec of magical network packet dust and blossom into a complete website. Or do whatever computer science deems is the absolute fastest way to send website data between computers. I’m much more worried about the state of web performance than I am about web education. But even if I was very worried about web education, I don’t think it’s the network’s job to deliver teachability.

Shipping source maps to production is a nice middle ground. There’s no hit on performance (source maps don’t get loaded unless you have DevTools open, which is, IMO, irrelevant to a real performance discussion) with the benefit of delivering debugging and learning benefits.

The downsides brought up in recent discussion boil down to:

  1. Sourcemaps require compilation time
  2. It allows people to, I dunno, steal your code or something

I don’t care about #2 (sorry), and #1 seems generally negligible for a small or what we think of as the average site, though I’m afraid I can’t speak for mega sites.

One thing I should add though is that source maps can even be generated for CSS-in-JS tooling, so for those that literally inject styles into the DOM for you, those source maps are injected as well. I’ve seen major slowdowns in those situations, so I would say definitely do not ship source maps to production if you can’t split them out of your main bundles. Otherwise, I’d vote strongly that you do.

The post Should I Use Source Maps in Production? appeared first on CSS-Tricks.

Writing Tests for React Applications Using Jest and Enzyme

Post pobrano z: Writing Tests for React Applications Using Jest and Enzyme

While it is important to have a well-tested API, solid test coverage is a must for any React application. Tests increase confidence in the code and helps prevent shipping bugs to users.

That’s why we’re going to focus on testing in this post, specifically for React applications. By the end, you’ll be up and running with tests using Jest and Enzyme.

No worries if those names mean nothing to you because that’s where we’re headed right now!

Installing the test dependencies

Jest is a unit testing framework that makes testing React applications pretty darn easy because it works seamlessly with React (because, well, the Facebook team made it, though it is compatible with other JavaScript frameworks). It serves as a test runner that includes an entire library of predefined tests with the ability to mock functions as well.

Enzyme is designed to test components and it’s a great way to write assertions (or scenarios) that simulate actions that confirm the front-end UI is working correctly. In other words, it seeks out components on the front end, interacts with them, and raises a flag if any of the components aren’t working the way it’s told they should.

So, Jest and Enzyme are distinct tools, but they complement each other well.

For our purposes, we will spin up a new React project using create-react-app because it comes with Jest configured right out of the box.

yarn create react-app my-app

We still need to install enzyme and enzyme-adapter-react-16 (that number should be based on whichever version of React version you’re using).

yarn add enzyme enzyme-adapter-react-16 --dev

OK, that creates our project and gets us both Jest and Enzyme in our project in two commands. Next, we need to create a setup file for our tests. We’ll call this file setupTests.js and place it in the src folder of the project.

Here’s what should be in that file:

import { configure } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';
configure({ adapter: new Adapter() });

This brings in Enzyme and sets up the adapter for running our tests.

To make things easier on us, we are going to write tests for a React application I have already built. Grab a copy of the app over on GitHub.

Taking snapshots of tests

Snapshot testing is used to keep track of changes in the app UI. If you’re wonder whether we’re dealing with literal images of the UI, the answer is no, but snapshots are super useful because they capture the code of a component at a moment in time so we can compare the component in one state versus any other possible states it might take.

The first time a test runs, a snapshot of the component code is composed and saved in a new __snapshots__ folder in the src directory. On test runs, the current UI is compared to the existing. Here’s a snapshot of a successful test of the sample project’s App component.

it("renders correctly", () => {
  const wrapper = shallow(
    <App />
  );
  expect(wrapper).toMatchSnapshot();
});

Every new snapshot that gets generated when the test suite runs will be saved in the __tests__ folder. What’s great about that Jest will check to see if the component matches is then on subsequent times when we run the test, Jest will check to see if the component matches the snapshot on subsequent tests. Here’s how that files looks.

Let’s create a conditions where the test fails. We’ll change the <h2> tag of our component from <h2>Random User</h2> to <h2>CSSTricks Tests</h2> and here’s what we get in the command line when the tests run:

If we want our change to pass the test, we either change the heading to what it was before, or we can update the snapshot file. Jest even provides instructions for how to update the snapshot right from the command line so there’s no need to update the snapshot manually:

Inspect your code changes or press `u` to update them.

So, that’s what we’ll do in this case. We press u to update the snapshot, the test passes, and we move on.

Did you catch the shallow method in our test snapshot? That’s from the Enzyme package and instructs the test to run a single component and nothing else — not even any child components that might be inside it. It’s a nice clean way to isolate code and get better information when debugging and is especially great for simple, non-interactive components.

In addition to shallow, we also have render for snapshot testing. What’s the difference, you ask? While shallow excludes child components when testing a component, render includes them while rendering to static HTML.

There is one more method in the mix to be aware of: mount. This is the most engaging type of test in the bunch because it fully renders components (like shallow and render) and their children (like render) but puts them in the DOM, which means it can fully test any component that interacts with the DOM API as well as any props that are passed to and from it. It’s a comprehensive test for interactivity. It’s also worth noting that, since it does a full mount, we’ll want to make a call to .unmount on the component after the test runs so it doesn’t conflict with other tests.

Testing Component’s Lifecycle Methods

Lifecycle methods are hooks provided by React, which get called at different stages of a component’s lifespan. These methods come in handy when handling things like API calls.
Since they are often used in React components, you can have your test suite cover them to ensure all things work as expected.

We do the fetching of data from the API when the component mounts. We can check if the lifecycle method gets called by making use of jest, which makes it possible for us to mock lifecycle methods used in React applications.

it('calls componentDidMount', () => {
  jest.spyOn(App.prototype, 'componentDidMount')
  const wrapper = shallow(<App />)
  expect(App.prototype.componentDidMount.mock.calls.length).toBe(1)
})

We attach spy to the component’s prototype, and the spy on the componentDidMount() lifecycle method of the component. Next, we assert that the lifecycle method is called once by checking for the call length.

Testing component props

How can you be sure that props from one component are being passed to another? We have a test confirm it, of course! The Enzyme API allows us to create a “mock” function so tests can simulate props being passed between components.

Let’s say we are passing user props from the main App component into a Profile component. In other words, we want the App to inform the Profile with details about user information to render a profile for that user.

First, let’s mock the user props:

const user = {
  name: 'John Doe',
  email: 'johndoe@gmail.com',
  username: 'johndoe',
  image: null
}

Mock functions look a lot like other tests in that they’re wrapped around the components. However, we’re using an additional describe layer that takes the component being tested, then allows us to proceed by telling the test the expected props and values that we expect to be passed.

describe ('<Profile />', () => {
  it ('contains h4', () => {
    const wrapper = mount(<Profile user={user} />)
    const value = wrapper.find('h4').text()
    expect(value).toEqual('John Doe')
  })
  it ('accepts user props', () => {
    const wrapper = mount(<Profile user={user} />);
    expect(wrapper.props().user).toEqual(user)
  })
})

This particular example contains two tests. In the first test, we pass the user props to the mounted Profile component. Then, we check to see if we can find a <h4> element that corresponds to what we have in the Profile component.

In the second test, we want to check if the props we passed to the mounted component equals the mock props we created above. Note that even though we are destructing the props in the Profile component, it does not affect the test.

Mock API calls

There’s a part in the project we’ve been using where an API call is made to fetch a list of users. And guess what? We can test that API call, too!

The slightly tricky thing about testing API calls is that we don’t actually want to hit the API. Some APIs have call limits or even costs for making making calls, so we want to avoid that. Thankfully, we can use Jest to mock axios requests. See this post for a more thorough walkthrough of using axios to make API calls.

First, we’ll create a new folder called __mock__ in the same directory where our __tests__ folder lives. This is where our mock request files will be created when the tests run.

module.exports = {
  get: jest.fn(() => {
    return Promise.resolve({
    data: [
      {
        id: 1,
        name: 'Jane Doe',
        email: 'janedoe@gmail.com',
        username: 'jdoe'
      }
    ]
    })
  })
}

We want to check and see that the GET request is made. We’ll import axios for that:

import axios from 'axios';

Just below the import statements, we need Jest to replace axios with our mock, so we add this:

jest.mock('axios')

The Jest API has a spyOn() method that takes an accessType? argument that can be used to check whether we are able to “get” data from an API call. We use jest.spyOn() to call the spied method, which we implemented in our __mock__ file, and it can be used with the shallow, render and mount tests we covered earlier.

it('fetches a list of users', () => {
  const getSpy = jest.spyOn(axios, 'get')
  const wrapper = shallow(
    <App />
  )
  expect(getSpy).toBeCalled()
})

We passed the test!

That’s a primer into the world of testing in a React application. Hopefully you now see the value that testing adds to a project and how relatively easy it can be to implement, thanks to the heavy lifting done by the joint powers of Jest and Enzyme.

Further reading

Why CSS Needs its Own Survey

Post pobrano z: Why CSS Needs its Own Survey

2016 was only three years ago, but that’s almost a whole other era in web development terms. The JavaScript landscape was in turmoil, with up-and-comer React — as well as a little-known framework called Vue — fighting to dethrone Angular.

Like many other developers, I felt lost. I needed some clarity, and I figured the best way to get it was simply to ask fellow coders what they used, and more importantly, what they enjoyed using. The result was the first ever edition of the now annual State of JavaScript survey.

The State of JavaScript 2018

Things have stabilized in the JavaScript world since then. Turns out you can’t really go wrong with any one of the big three frameworks, and even less mainstream options, like Ember, have managed to build up passionate communities and show no sign of going anywhere.

But while all our attention was fixated on JavaScript, trouble was brewing in CSS land. For years, my impression of CSS’s evolution was slow, incremental progress. Back then, I was pretty sure border-radius support represented the crowning, final achievement of web browser technology.

But all of a sudden, things started picking up. Flexbox came out, representing the first new and widely adopted layout method in over a decade. And Grid came shortly after that, sweeping away years of hacky grid frameworks into the gutter of bad CSS practices.

Something even crazier happened: now that the JavaScript people had stopped creating a new framework every two weeks, they decided to use all their extra free time trying to make CSS even better! And thus CSS-in-JS was born.

And now it’s 2019, and the Flexbox Cheatsheet tab I’ve kept open for the past two years has now been joined by a Grid Cheatsheet, because no matter how many times I use them, I still need to double-check the syntax. And despite writing a popular introduction to CSS-in-JS, I still lazily default to familiar Sass for new projects, promising myself that I’ll „do things properly” the next time.

All this to say that I feel just as lost and confused about CSS in 2019 as I did about JavaScript in 2016. It’s high time CSS got a survey of its own.

Starting from scratch

Coming up with the idea for a CSS survey was easy, but deciding on the questions themselves was far from straightforward. Like I said, I didn’t feel confident in my own CSS knowledge, and simply asking about Sass vs. Less for the 37th time felt like a missed opportunity…

Thankfully, the CSS Gods decided to smile down upon me: while attending the DotJS conference in France I discovered that, not only did fellow speaker Florian Rivoal live in Kyoto, Japan, just like me; but that he was a member of the CSS Working Group! In other words, one of the people who knows the most about CSS on the planet was living a few train stops away from me!

Florian was a huge help in coming up with the overall structure and content of the survey. And he also helped me realize how little I really knew about CSS.

Kyoto, Japan: a hotbed of CSS activity (Photo by Jisu Han)

You don’t know CSS

I’m not only talking about obscure CSS properties here, or even new up-and-coming ones, but about how CSS itself is developed. For example, did you know that the development of the CSS Grid spec was sponsored by Bloomberg, because they needed a way to port the layout of their famous terminal to the web?

Did you ever stop to wonder what top: 30px is supposed to mean on a circular screen, such as the one on a smartwatch? Or did you know that some people are laying out entire printed books in CSS, effectively replacing software like InDesign?

Talking with Florian really expanded my mind to how broad and interesting CSS truly is, and convinced me doing the survey was worth it.

„What do you mean, ‘Make the <table> circular’?” Photo by Artur Łuczka

About that divide…

The idea of a CSS survey became all the more important as my new-found admiration for CSS seemed to coincide with a general sentiment that HTML and CSS mastery were becoming under-appreciated skills in the face of JavaScript hegemony.

Myself, personally, I’ve always enjoyed being a generalist in the sense that I happily hop from one side of the great divide to another whenever I feel like it. At the same time, I’m also wholly convinced that the world needs specialists like Florian; people who dedicate their lives to championing and improving a single aspect of the web.

Devaluing the work the work of generalists is not only unfair, but it’s also counter-productive — after all, HTML and CSS are the foundation on which all modern JavaScript frameworks are built; and on the other hand, new patterns and approaches pioneered by CSS-in-JS libraries will hopefully find their way back into vanilla CSS sooner or later.

Thankfully, I feel like a minority of developers hold those views, and those who do generally hold them do so out of ignorance for what the „other side” really stands for more than any well-informed opinion.

So that’s where the survey comes in: I’m not saying I can fill up the divide, but maybe I can throw a couple walkways across, or distribute some jetpacks — you know, whatever works. 🚀

If that sounds good, then the first step is — you guessed it — taking the survey!

Take Survey

The post Why CSS Needs its Own Survey appeared first on CSS-Tricks.

Recreating the Facebook Messenger Gradient Effect with CSS

Post pobrano z: Recreating the Facebook Messenger Gradient Effect with CSS

One Sunday morning, I woke up a little earlier than I would’ve liked to, thanks to the persistent buzzing of my phone. I reached out, tapped into Facebook Messenger, and joined the conversation. Pretty soon my attention went from the actual conversations to the funky gradient effect of the message bubbles containing them. Let me show you what I mean:

This is a new feature of Messenger, which allows you to choose a gradient instead of a plain color for the background of the chat messages. It’s currently available on the mobile application as well as Facebook’s site, but not yet on Messenger’s site. The gradient appears “fixed” so that chat bubbles appear to change background color as they scroll vertically.

I thought this looked like something that could be done in CSS, so… challenge accepted!

Let’s walk through my thought process as I attempted to recreate it and explain the CSS features that were used to make it work. Also, we’ll see how Facebook actually implemented it (spoiler alert: not the way I did) and how the two approaches compare.

Getting our hands dirty

First, let’s look at the example again to see what exactly it is that we’re trying to achieve here.

In general, we have a pretty standard messaging layout: messages are divided into bubbles going from top to bottom, ours on the right and the other people in the chat on the left. The ones on the left all have a gray background color, but the ones on the right look like they’re sharing the same fixed background gradient. That’s pretty much it!

Step 1: Set up the layout

This part is pretty simple: let’s arrange the messages in an ordered list and apply some basic CSS to make it look more like an actual messaging application:

<ol class="messages">
  <li class="ours">Hi, babe!</li>
  <li class="ours">I have something for you.</li>
  <li>What is it?</li>
  <li class="ours">Just a little something.</li>
  <li>Johnny, it’s beautiful. Thank you. Can I try it on now?</li>
  <li class="ours">Sure, it’s yours.</li>
  <li>Wait right here.</li>
  <li>I’ll try it on right now.</li>
</ol>

When it comes to dividing the messages to the left and the right, my knee-jerk reaction was to use floats. We could use float: left for messages on the left and float: right for messages on the right to have them stick to different edges. Then, we’d apply clear: both to on each message so they stack. But there’s a much more modern approach — flexbox!

We can use flexbox to stack the list items vertically with flex-direction: column and tell all the children to stick to the left edge (or “align the cross-start margin edges of the flex children with cross-start margin edges of the lines,” if you prefer the technical terms) with align-items: flex-start. Then, we can overwrite the align-items value for individual flex items by setting align-self: flex-end on them.

What, you mean you couldn’t visualize the code based on that? Fine, here’s how that looks:

.messages {
  /* Flexbox-specific styles */
  display: flex;
  flex-direction: column;
  align-items: flex-start;

  /* General styling */
  font: 16px/1.3 sans-serif;
  height: 300px;
  list-style-type: none;
  margin: 0 auto;
  padding: 8px;
  overflow: auto;
  width: 200px;
}

/* Default styles for chat bubbles */
.messages li {
  background: #eee;
  border-radius: 8px;
  padding: 8px;
  margin: 2px 8px 2px 0;
}

/* Styles specific to our chat bubbles */
.messages li.ours {
  align-self: flex-end; /* Stick to the right side, please! */
  margin: 2px 0 2px 8px;
}

Some padding and colors here and there and this already looks similar enough to move on to the fun part.

Step 2: Let’s color things in!

The initial idea for the gradient actually came to me from this tweet by Matthias Ott (that Chris recreated in another post):

This is a nasty hack with a pseudo-element on top of the text and mix-blend-mode doesn't work in IE / Edge, but: Yes, this is possible to do with CSS! 😅https://t.co/FLKGvd1YoI

— Matthias Ott (@m_ott) December 3, 2018

The key clue here is mix-blend-mode, which is a CSS property that allows us to control how the content of an element blends in with what’s behind it. It’s a feature that has been present in Photoshop and other similar tools for a while, but is fairly new to the web. There’s an almanac entry for the property that explains all of its many possible values.

One of the values is screen: it takes the values of the pixels of the background and foreground, inverts them, multiplies them, and inverts them once more. This results in a color that is brighter than the original background color.

The description can seem a little confusing, but what it essentially means is that if the background is monochrome, wherever the background is black, the foreground pixels are shown fully and wherever it is white, white remains.

With mix-blend-mode: screen; on the foreground, we’ll see more of the foreground as the background is darker.

So, for our purposes, the background will be the chat window itself and the foreground will contain an element with the desired gradient set as the background that’s positioned over the background. Then, we apply the appropriate blend mode to the foreground element and restyle the background. We want the background to be black in places where we want the gradient to be shown and white in other places, so we’ll style the bubbles by giving them a plain black background and white text. Oh, and let’s remember to add pointer-events: none to the foreground element so the user can interact with the underlying text.

At this point, I also changed the original HTML a little. The entire chat is a wrapper in an additional container that allows the gradient to stay “fixed” over the scrollable part of the chat:

.messages-container:after {
  content: '';
  background: linear-gradient(rgb(255, 143, 178) 0%, rgb(167, 151, 255) 50%, rgb(0, 229, 255) 100%);
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  width: 100%;
  mix-blend-mode: screen;
  pointer-events: none;
}

.messages li {
  background: black;
  color: white;
  /* rest of styles */
}

The result looks something like this:

The gradient applied to the chat bubbles

Step 3: Exclude some messages from the gradient

Now the gradient is being shown where the text bubbles are under it! However, we only want it to be shown over our bubbles — the ones along the right edge. A hint to how that can be achieved is hidden in MDN’s description of the mix-blend-mode property:

The mix-blend-mode CSS property sets how an element’s content should blend with the content of the element’s parent and the element’s background.

That’s right! The background. Of course, the effect only takes into account the HTML elements that are behind the current element and have a lower stack order. Fortunately, the stacking order of elements can easily be changed with the z-index property. So all we have to do is to give the chat bubbles on the left a higher z-index than that of the foreground element and they will be raised above it, outside of the influence of mix-blend-mode! Then we can style them however we want.

The gradient applied to the chat bubbles.

Let’s talk browser support

At the time of writing, mix-blend-mode is not supported at all in Internet Explorer and Edge. In those browsers, the gradient is laid over the whole chat and others’ bubbles appear on top of it, which is not an ideal solution.

This browser support data is from Caniuse, which has more detail. A number indicates that browser supports the feature at that version and up.

Desktop

Chrome Opera Firefox IE Edge Safari
41 29 32 No No TP

Mobile / Tablet

iOS Safari Opera Mobile Opera Mini Android Android Chrome Android Firefox
12.2 46 No 67 71 64

So, this is what we get in unsupported browsers:

How browsers that don’t support mix-blend-mode render the chat.

Fortunately, all the browsers that support mix-blend-mode also support CSS Feature Queries. Using them allows us to write fallback styles for unsupported browsers first and include the fancy effects for the browsers that support them. This way, even if a user can’t see the full effect, they can still see the whole chat and interact with it:

A simplified UI for older browsers, falling back to a plain cyan background color.

Here’s the final Pen with the full effect and fallback styles:

See the Pen
Facebook Messenger-like gradient coloring in CSS
by Stepan Bolotnikov (@Stopa)
on CodePen.

Now let’s see how Facebook did it

Turns out that Facebook’s solution is almost the opposite of what we’ve covered here. Instead of laying the gradient over the chat and cutting holes in it, they apply the gradient as a fixed background image to the whole chat. The chat itself is filled with a whole bunch of empty elements with white backgrounds and borders, except where the gradient should be visible.

The final HTML rendered by the Facebook Messenger React app is pretty verbose and hard to navigate, so I recreated a minimal example to demonstrate it. A lot of the empty HTML elements can be switched for pseudo-elements instead:

See the Pen
Facebook Messenger-like gradient coloring in CSS: The Facebook Way
by Stepan Bolotnikov (@Stopa)
on CodePen.

As you can see, the end result looks similar to the mix-blend-mode solution, but with a little bit of extra markup. Additionally, their approach provides more flexibility for rich content, like images and emojis . The mix-blend-mode approach doesn’t really work if the background is anything but monochrome and I haven’t been able to come up with a way to “raise” inner content above the gradient or get around this limitation in another way.

Because of this limitation, it’s wiser to use Facebook’s approach in an actual chat application. Still, our solution using mix-blend-mode showcases an interesting way to use one of the most under-appreciated CSS properties in modern web design and hopefully it has given you some ideas on what you could do with it!

The post Recreating the Facebook Messenger Gradient Effect with CSS appeared first on CSS-Tricks.

CSS Variables + calc() + rgb() = Enforcing High Contrast Colors

Post pobrano z: CSS Variables + calc() + rgb() = Enforcing High Contrast Colors

As you may know, the recent updates and additions to CSS are extremely powerful. From Flexbox to Grid, and — what we’re concerned about here — Custom Properties (aka CSS variables), all of which make robust and dynamic layouts and interfaces easier than ever while opening up many other possibilities we used to only dream of.

The other day, I was thinking that there must be a way to use Custom Properties to color an element’s background while maintaining a contrast with the foreground color that is high enough (using either white or black) to pass WCAG AA accessibility standards.

It’s astonishingly efficient to do this in JavaScript with a few lines of code:

var rgb = [255, 0, 0];

function setForegroundColor() {
  var sum = Math.round(((parseInt(rgb[0]) * 299) + (parseInt(rgb[1]) * 587) + (parseInt(rgb[2]) * 114)) / 1000);
  return (sum > 128) ? 'black' : 'white';
}

This takes the red, green and blue (RGB) values of an element’s background color, multiplies them by some special numbers (299, 587, and 144, respectively), adds them together, then divides the total by 1,000. When that sum is greater than 128, it will return black; otherwise, we’ll get white. Not too bad.

The only problem is, when it comes to recreating this in CSS, we don’t have access to a native if statement to evaluate the sum. So,how can we replicate this in CSS without one?

Luckily, like HTML, CSS can be very forgiving. If we pass a value greater than 255 into the RGB function, it will get capped at 255. Same goes for numbers lower than 0. Even negative integers will get capped at 0. So, instead of testing whether our sum is greater or less than 128, we subtract 128 from our sum, giving us either a positive or negative integer. Then, if we multiply it by a large negative value (e.g. -1,000), we end up with either very large positive or negative values that we can then pass into the RGB function. Like I said earlier, this will get capped to the browser’s desired values.

Here is an example using CSS variables:

:root {
  --red: 28;
  --green: 150;
  --blue: 130;

  --accessible-color: calc(
    (
      (
        (var(--red) * 299) +
        (var(--green) * 587) +
        (var(--blue) * 114) /
        1000
      ) - 128
    ) * -1000
  );
}

.button {
  color:
    rgb(
      var(--accessible-color),
      var(--accessible-color),
      var(--accessible-color)
    );
  background-color:
    rgb(
      var(--red),
      var(--green),
      var(--blue)
    );
}

If my math is correct (and it’s very possible that it’s not) we get a total of 16,758, which is much greater than 255. Pass this total into the rgb() function for all three values, and the browser will set the text color to white.

At this point, everything seems to be working in both Chrome and Firefox, but Safari is a little cranky and gives a different result. At first, I thought this might be because Safari was not capping the large values I was providing in the function, but after some testing, I found that Safari didn’t like the division in my calculation for some reason.

Taking a closer look at the calc() function, I noticed that I could remove the division of 1,000 by increasing the value of 128 to 128,000. Here’s how that looks so far:

:root {
  --red: 28;
  --green: 150;
  --blue: 130;

  --accessible-color: calc(
    (
      (
        (var(--red) * 299) +
        (var(--green) * 587) +
        (var(--blue) * 114)
      ) - 128000 /* HIGHLIGHT */
    ) * -1000
  );
}

.button {
  color:
    rgb(
      var(--accessible-color),
      var(--accessible-color),
      var(--accessible-color)
    );
  background-color:
    rgb(
      var(--red),
      var(--green),
      var(--blue)
    );
}

Throw in a few range sliders to adjust the color values, and there you have it: a dynamic UI element that can swap text color based on its background-color while maintaining a passing grade with WCAG AA.

See the Pen
CSS Only Accessible Button
by Josh Bader (@joshbader)
on CodePen.

Putting this concept to practical use

Below is a Pen showing how this technique can be used to theme a user interface. I have duplicated and moved the --accessible-color variable into the specific CSS rules that require it, and to help ensure backgrounds remain accessible based on their foregrounds, I have multiplied the --accessible-color variable by -1 in several places. The colors can be changed by using the controls located at the bottom-right. Click the cog/gear icon to access them.

See the Pen
CSS Variable Accessible UI
by Josh Bader (@joshbader)
on CodePen.

There are other ways to do this

A little while back, Facundo Corradini explained how to do something very similar in this post. He uses a slightly different calculation in combination with the hsl function. He also goes into detail about some of the issues he was having while coming up with the concept:

Some hues get really problematic (particularly yellows and cyans), as they are displayed way brighter than others (e.g. reds and blues) despite having the same lightness value. In consequence, some colors are treated as dark and given white text despite being extremely bright.

What in the name of CSS is going on?

He goes on to mention that Edge wasn’t capping his large numbers, and during my testing, I noticed that sometimes it was working and other times it was not. If anyone can pinpoint why this might be, feel free to share in the comments.

Further, Ana Tudor explains how using filter + mix-blend-mode can help contrast text against more complex backgrounds. And, when I say complex, I mean complex. She even goes so far as to demonstrate how text color can change as pieces of the background color change — pretty awesome!

Also, Robin Rendle explains how to use mix-blend-mode along with pseudo elements to automatically reverse text colors based on their background-color.

So, count this as yet another approach to throw into the mix. It’s incredibly awesome that Custom Properties open up these sorts of possibilities for us while allowing us to solve the same problem in a variety of ways.

The post CSS Variables + calc() + rgb() = Enforcing High Contrast Colors appeared first on CSS-Tricks.

Writing Animations That Bring Your Site to Life

Post pobrano z: Writing Animations That Bring Your Site to Life

Web animation is one of the factors that can strongly enhance your website’s look and feel. Sadly, unlike mobile apps, there aren’t as many websites using animation to their benefit as you would think. We don’t want to count yours among those, so this article is for you and anyone else looking for ways to use animation for a better user experience! Specifically, we’re going to learn how to make web interactions delightful using CSS animations.

Here’s what we’re going to build together:


Before we move ahead, it’s worth mentioning that I’m going to assume you have at least some familiarity with modern front-end frameworks and a basic understanding of CSS animations. If you don’t, then no fear! CSS-Tricks has a great guides on React and Vue, as well as a thorough almanac post on the CSS animation property.

Good? OK, let’s talk about why we’d want to use animation in the first place and cover some baseline information about CSS animations.

Why would we to animate anything?

We could probably do an entire post on this topic alone. Oh, wait! Sarah Drasner already did that and her points are both poignant and compelling.

But, to sum things up based on my own experiences:

  • Animations enhance the way users interact with an interface. For example, smart animations can reduce cognitive load by giving users better context between page transitions.
  • They can provide clear cues to users, like where we want them to focus attention.
  • Animations serve as another design pattern in and of themselves, helping users to get emotionally attached to and engage with the interface.
  • Another benefit of using animations is that they can create a perception that a site or app loads faster than it actually does.

A couple of house rules with animations

Have you ever bumped into a site that animates all the things? Wow, those can be jarring. So, here’s a couple of things to avoid when working with animations so our app doesn’t fall into the same boat:

  • Avoid animating CSS properties other than transform and opacity. If other properties have to be animated, like width or height, then make sure there aren’t a lot of layout changes happening at the same time. There’s actually a cost to animations and you can see exactly how much by referring to CSS Triggers.
  • Also, just because animations can create perceived performance gains, there’s actually a point of diminishing return when it comes to using them. Animating too many elements at the same time may result in decreased performance.

Now we can get our hands dirty with some code!

Let’s build a music app

We’re going to build the music app we looked at earlier, which is inspired by Aurélien Salomon’s Dribbble shot. I chose this example so that we can focus on animations, not only within a component, but also between different routes. We’ll build this app using Vue and create animations using vanilla (i.e. no framework) CSS.

Animations should go hand-in-hand with UI development. Creating UI before defining their movement is likely to cost much more time. In this case, the Dribbble shot provides that scope for us.

Let’s start with the development.

Step 1: Spin up the app locally

First things first. We need to set up a new Vue project. Again, we’re assuming some base-level understanding of Vue here, so please check out the Learning Vue guide for more info on setting up.

We need a couple of dependencies for our work, notably vue-router for transitioning between views and sass-loader so we can write in Sass and compile to CSS. Here’s a detailed tutorial on using routes and Sass can be installed by pointing the command line at the project directory and using npm install -D sass-loader node-sass.

We have what we need!

Step 2: Setting up routes

For creating routes, we’re first going to create two bare minimum components — Artists.vue and Tracks.vue. We’ll drop a new file in the src folder called router.js and add routes for these components as:

import Vue from 'vue'
import Router from 'vue-router'
import Artists from './components/Artists.vue'
import Tracks from './components/Tracks.vue'

Vue.use(Router)
export default new Router({
	mode: 'history',
	routes: [
		{
			path: '/',
			name: 'artists',
			component: Artists
		},
		{
			path: '/:id',
			name: 'tracks',
			component: Tracks
		}
	]
})

Import router.js into the main.js and inject it to the Vue instance. Lastly, replace the content of your App.vue by <router-view/>.

Step 3: Create the components and content for the music app

We need two components that we’ll transition between with animation. Those are going to be:

  1. Artists.vue: a grid of artists
  2. Tracks.vue: An artist image with a back button

If you wanna jump ahead a bit, here are some assets to work with:

  1. Images and sample data in JSON format.
  2. Content for the components

When all is said and done, the two views will come out to something like this:

Artists.vue (left) and Tracks.vue (right)

Step 4: Animate!

Here we are, the part we’ve really wanted to get to all this time. The most important animation in the app is transitioning from Artists to Tracks when clicking on an artist. It should feel seamless where clicking on an artist image puts that image in focus while transitioning from one view into the next. This is exactly the type of animation that we rarely see in apps but can drastically reduce cognitive load for users.

To make sure we’re all on the same page, we’re going to refer to the first image in the sequence as the “previous” image and the second one as the „current” image. Getting the effect down is relatively easy as long as we know the dimensions and position of the previous image in the transition. We can animate the current image by transforming it as per previous image.

The formula that I’m using is transform: translate(x, y) scale(n), where n is equal to the size of previous image divided by the size of current image. Note that we can use a static value of n since the dimensions are fixed for all the images. For example, the image size in the Artists view is 190x190 and 240x240 in the Tracks view. Thus, we can replace n by 190/240 = 0.791. That means the transform value becomes translate(x, y) scale(0.791) in our equation.

Animating from Artists to Tracks

Next thing is to find x and y. We can get these values though click event in the Artists view as:

const {x, y} = event.target.getBoundingClientRect()

…and then send these values to the Tracks view, all while switching the route. Since we aren’t using any state management library, the two components will communicate via their parent component, which is the top level component, App.vue. In App.vue, let’s create a method that switches the route and sends the image info as params.

gotoTracks(position, artistId) {
	this.$router.push({
		name: 'tracks',
		params: {
			id: artistId,
			position: position
		}
	})
}

Here’s the relevant code from the repo to reference, in case you’re interested.

Since we have received the position and ID of the image in Tracks, we have all the required data to show and animate it. We’ll first fetch artist information (specifically the name and image URL) using artist ID.

To animate the image, we need to calculate the transform value from the image’s starting position. To set the transform value, I’m using CSS custom properties, which can be done with CSS-in-JS techniques as well. Note that the image’s position that we received through props will be relative to window. Therefore we’ll have to subtract some fixed offset caused by the padding of the container <div> to even out our math.

const { x, y } = this.$route.params.position
// padding-left
const offsetLeft = 100
// padding-top
const offsetTop = 30

// Set CSS custom property value
document.documentElement.style.setProperty(
	'--translate', 
	`translate(${x - offsetLeft}px, ${y - offsetTop}px) scale(0.792)`
)

We’ll use this value to create a keyframe animation to move the image:

@keyframes move-image {
	from {
		transform: var(--translate);
	}
}

This gets assigned to the CSS animation:

.image {
	animation: move-image 0.6s;
}

…and it will animate the image from this transform value to its original position on component load.

Transitioning from Artists to Tracks

We can use the same technique when going the opposite direction, Tracks to Artists. As we already have the clicked image’s position stored in the parent component, we can pass it to props for Artists as well.

Transitioning from Tracks to Artists

Step 5: Show the tracks!

It’s great that we can now move between our two views seamlessly, but the Tracks view is pretty sparse at the moment. So let’s add the track list for the selected artist.

We’ll create an empty white box and a new keyframe to slide it upwards on page load. Then we’ll add three subsections to it: Recent Tracks, Popular Tracks, and Playlist. Again, if you want to jump ahead, feel free to either reference or copy the final code from the repo.

The Tracks view with content

Recent Tracks is the row of thumbnails just below the artist image where each thumbnail includes the track name and track length below it. Since we’re covering animations here, we’ll create a scale-up animation, where the image starts invisible (opacity: 0) and a little smaller than it’s natural size (scale(0.7)), then is revealed (opacity: 1 )and scales up to its natural size (transform: none).

.track {
	opacity: 0;
	transform: scale(0.7);
	animation: scale-up 1s ease forwards;
}

@keyframes scale-up {
	to {
		opacity: 1;
		transform: none;
	}
}

The Popular Tracks list and Playlist sit side-by-side below the Recent Tracks, where Popular tracks takes up most of the space. We can slide them up a bit on initial view with another set of keyframes:

.track {
	...
	animation: slide-up 1.5s;
}

@keyframes slide-up {
	from {
		transform: translateY(140px);
	}
}

To make the animation feel more natural, we’ll create a stagger effect so the Recent Tracks lead a little ahead of the Popular Tracks and Playlist using an incremental animation delay to each item.

@for $i from 1 to 5 {
	&:nth-child(#{$i + 1}) {
		animation-delay: #{$i * 0.05}s;
	}
}

The code above is basically looking for each child element, then adding a 0.05 second delay to each element it finds. So, for example, the first child gets a 0.05 second delay, the second child gets a 0.10 second delay and so on.

Check out how nice and natural this all looks:

Bonus: micro-interactions!

One of the fun things about working with animations is thinking through the small details because they’re what tie things together and add delight to the user experience. We call these micro-interactions and they serve a good purpose by providing visual feedback when an action is performed.

Depending on the complexity of the animations, we might need a library like anime.js or GSAP. This example is pretty straightforward, so we can accomplish everything we need by writing some CSS.

First micro-interaction: The volume icon

Let’s first get a volume icon in SVG format (Noun Project and Material Design are good sources). On click, we’ll animate-in and out its path element to show the level of volume. For this, we’ll create a method which switches its CSS class according to the volume level.

<svg @click="changeVolume">
	<g :class="`level-${volumeLevel}`">
		<path d="..."/> <!-- volume level 1 -->
		<path d="..."/> <!-- volume level 2 -->
		<path d="..."/> <!-- volume level 3 -->
		<polygon points="..."/>
	</g>
</svg>

Based on this class, we can show and hide certain path elements as:

path {
	opacity: 0;
	transform-origin: left;
	transform: translateX(-5px) scale(0.6);
	transition: transform 0.25s, opacity 0.2s;
}

.level-1 path:first-child,
.level-2 path:first-child,
.level-2 path:nth-child(2),
.level-3 path {
	opacity: 1;
	transform: none;
}
The animated volume control

Second micro-interaction: The favorite icon

Do you like it when you click on Twitter’s heart button? That’s because it feels unique and special by the way it animates on click. We’ll make something similar but real quick. For this, we first get an SVG heart icon and add it to the the markup. Then we’ll add a bouncy animation to it that’s triggered on click.

@keyframes bounce {
	0%, 100% {
		transform: none;
	}
	30% {
		transform: scale(1.3);
	}
	60% {
		transform: scale(0.9);
	}
}

Another fun thing we can do is add other small heart icons around it with random sizes and positions. Ideally, we’d add a few absolute-positioned HTML elements that a heart as the background. Let’s Arrange each of them as below by setting their left and bottom values.

We’ll also include a fade away effect so the icons appear to dissolve as they move upward by adding a keyframe animation on the same click event.

@keyframes float-upwards {
	0%, 100% {
		opacity: 0;
	}
	50% {
		opacity: 0.7;
	}
	50%, 100% {
		transform: translate(-1px, -5px);
	}
}
The animated favorite button

Summing up

That’s all! I hope you find all this motivating to try animations on your own websites and projects.

While writing this, I also wanted to expand on the fundamental animation principles we glossed over earlier because I believe that they help choose animation durations, and avoid non-meaningful animations. That’s important to discuss because doing animations correctly is better than doing them at all. But this sounds like a whole another topic to be covered in a future article.

The post Writing Animations That Bring Your Site to Life appeared first on CSS-Tricks.

Writing Animations That Bring Your Site to Life

Post pobrano z: Writing Animations That Bring Your Site to Life

Web animation is one of the factors that can strongly enhance your website’s look and feel. Sadly, unlike mobile apps, there aren’t as many websites using animation to their benefit as you would think. We don’t want to count yours among those, so this article is for you and anyone else looking for ways to use animation for a better user experience! Specifically, we’re going to learn how to make web interactions delightful using CSS animations.

Here’s what we’re going to build together:


Before we move ahead, it’s worth mentioning that I’m going to assume you have at least some familiarity with modern front-end frameworks and a basic understanding of CSS animations. If you don’t, then no fear! CSS-Tricks has a great guides on React and Vue, as well as a thorough almanac post on the CSS animation property.

Good? OK, let’s talk about why we’d want to use animation in the first place and cover some baseline information about CSS animations.

Why would we to animate anything?

We could probably do an entire post on this topic alone. Oh, wait! Sarah Drasner already did that and her points are both poignant and compelling.

But, to sum things up based on my own experiences:

  • Animations enhance the way users interact with an interface. For example, smart animations can reduce cognitive load by giving users better context between page transitions.
  • They can provide clear cues to users, like where we want them to focus attention.
  • Animations serve as another design pattern in and of themselves, helping users to get emotionally attached to and engage with the interface.
  • Another benefit of using animations is that they can create a perception that a site or app loads faster than it actually does.

A couple of house rules with animations

Have you ever bumped into a site that animates all the things? Wow, those can be jarring. So, here’s a couple of things to avoid when working with animations so our app doesn’t fall into the same boat:

  • Avoid animating CSS properties other than transform and opacity. If other properties have to be animated, like width or height, then make sure there aren’t a lot of layout changes happening at the same time. There’s actually a cost to animations and you can see exactly how much by referring to CSS Triggers.
  • Also, just because animations can create perceived performance gains, there’s actually a point of diminishing return when it comes to using them. Animating too many elements at the same time may result in decreased performance.

Now we can get our hands dirty with some code!

Let’s build a music app

We’re going to build the music app we looked at earlier, which is inspired by Aurélien Salomon’s Dribbble shot. I chose this example so that we can focus on animations, not only within a component, but also between different routes. We’ll build this app using Vue and create animations using vanilla (i.e. no framework) CSS.

Animations should go hand-in-hand with UI development. Creating UI before defining their movement is likely to cost much more time. In this case, the Dribbble shot provides that scope for us.

Let’s start with the development.

Step 1: Spin up the app locally

First things first. We need to set up a new Vue project. Again, we’re assuming some base-level understanding of Vue here, so please check out the Learning Vue guide for more info on setting up.

We need a couple of dependencies for our work, notably vue-router for transitioning between views and sass-loader so we can write in Sass and compile to CSS. Here’s a detailed tutorial on using routes and Sass can be installed by pointing the command line at the project directory and using npm install -D sass-loader node-sass.

We have what we need!

Step 2: Setting up routes

For creating routes, we’re first going to create two bare minimum components — Artists.vue and Tracks.vue. We’ll drop a new file in the src folder called router.js and add routes for these components as:

import Vue from 'vue'
import Router from 'vue-router'
import Artists from './components/Artists.vue'
import Tracks from './components/Tracks.vue'

Vue.use(Router)
export default new Router({
	mode: 'history',
	routes: [
		{
			path: '/',
			name: 'artists',
			component: Artists
		},
		{
			path: '/:id',
			name: 'tracks',
			component: Tracks
		}
	]
})

Import router.js into the main.js and inject it to the Vue instance. Lastly, replace the content of your App.vue by <router-view/>.

Step 3: Create the components and content for the music app

We need two components that we’ll transition between with animation. Those are going to be:

  1. Artists.vue: a grid of artists
  2. Tracks.vue: An artist image with a back button

If you wanna jump ahead a bit, here are some assets to work with:

  1. Images and sample data in JSON format.
  2. Content for the components

When all is said and done, the two views will come out to something like this:

Artists.vue (left) and Tracks.vue (right)

Step 4: Animate!

Here we are, the part we’ve really wanted to get to all this time. The most important animation in the app is transitioning from Artists to Tracks when clicking on an artist. It should feel seamless where clicking on an artist image puts that image in focus while transitioning from one view into the next. This is exactly the type of animation that we rarely see in apps but can drastically reduce cognitive load for users.

To make sure we’re all on the same page, we’re going to refer to the first image in the sequence as the “previous” image and the second one as the „current” image. Getting the effect down is relatively easy as long as we know the dimensions and position of the previous image in the transition. We can animate the current image by transforming it as per previous image.

The formula that I’m using is transform: translate(x, y) scale(n), where n is equal to the size of previous image divided by the size of current image. Note that we can use a static value of n since the dimensions are fixed for all the images. For example, the image size in the Artists view is 190x190 and 240x240 in the Tracks view. Thus, we can replace n by 190/240 = 0.791. That means the transform value becomes translate(x, y) scale(0.791) in our equation.

Animating from Artists to Tracks

Next thing is to find x and y. We can get these values though click event in the Artists view as:

const {x, y} = event.target.getBoundingClientRect()

…and then send these values to the Tracks view, all while switching the route. Since we aren’t using any state management library, the two components will communicate via their parent component, which is the top level component, App.vue. In App.vue, let’s create a method that switches the route and sends the image info as params.

gotoTracks(position, artistId) {
	this.$router.push({
		name: 'tracks',
		params: {
			id: artistId,
			position: position
		}
	})
}

Here’s the relevant code from the repo to reference, in case you’re interested.

Since we have received the position and ID of the image in Tracks, we have all the required data to show and animate it. We’ll first fetch artist information (specifically the name and image URL) using artist ID.

To animate the image, we need to calculate the transform value from the image’s starting position. To set the transform value, I’m using CSS custom properties, which can be done with CSS-in-JS techniques as well. Note that the image’s position that we received through props will be relative to window. Therefore we’ll have to subtract some fixed offset caused by the padding of the container <div> to even out our math.

const { x, y } = this.$route.params.position
// padding-left
const offsetLeft = 100
// padding-top
const offsetTop = 30

// Set CSS custom property value
document.documentElement.style.setProperty(
	'--translate', 
	`translate(${x - offsetLeft}px, ${y - offsetTop}px) scale(0.792)`
)

We’ll use this value to create a keyframe animation to move the image:

@keyframes move-image {
	from {
		transform: var(--translate);
	}
}

This gets assigned to the CSS animation:

.image {
	animation: move-image 0.6s;
}

…and it will animate the image from this transform value to its original position on component load.

Transitioning from Artists to Tracks

We can use the same technique when going the opposite direction, Tracks to Artists. As we already have the clicked image’s position stored in the parent component, we can pass it to props for Artists as well.

Transitioning from Tracks to Artists

Step 5: Show the tracks!

It’s great that we can now move between our two views seamlessly, but the Tracks view is pretty sparse at the moment. So let’s add the track list for the selected artist.

We’ll create an empty white box and a new keyframe to slide it upwards on page load. Then we’ll add three subsections to it: Recent Tracks, Popular Tracks, and Playlist. Again, if you want to jump ahead, feel free to either reference or copy the final code from the repo.

The Tracks view with content

Recent Tracks is the row of thumbnails just below the artist image where each thumbnail includes the track name and track length below it. Since we’re covering animations here, we’ll create a scale-up animation, where the image starts invisible (opacity: 0) and a little smaller than it’s natural size (scale(0.7)), then is revealed (opacity: 1 )and scales up to its natural size (transform: none).

.track {
	opacity: 0;
	transform: scale(0.7);
	animation: scale-up 1s ease forwards;
}

@keyframes scale-up {
	to {
		opacity: 1;
		transform: none;
	}
}

The Popular Tracks list and Playlist sit side-by-side below the Recent Tracks, where Popular tracks takes up most of the space. We can slide them up a bit on initial view with another set of keyframes:

.track {
	...
	animation: slide-up 1.5s;
}

@keyframes slide-up {
	from {
		transform: translateY(140px);
	}
}

To make the animation feel more natural, we’ll create a stagger effect so the Recent Tracks lead a little ahead of the Popular Tracks and Playlist using an incremental animation delay to each item.

@for $i from 1 to 5 {
	&:nth-child(#{$i + 1}) {
		animation-delay: #{$i * 0.05}s;
	}
}

The code above is basically looking for each child element, then adding a 0.05 second delay to each element it finds. So, for example, the first child gets a 0.05 second delay, the second child gets a 0.10 second delay and so on.

Check out how nice and natural this all looks:

Bonus: micro-interactions!

One of the fun things about working with animations is thinking through the small details because they’re what tie things together and add delight to the user experience. We call these micro-interactions and they serve a good purpose by providing visual feedback when an action is performed.

Depending on the complexity of the animations, we might need a library like anime.js or GSAP. This example is pretty straightforward, so we can accomplish everything we need by writing some CSS.

First micro-interaction: The volume icon

Let’s first get a volume icon in SVG format (Noun Project and Material Design are good sources). On click, we’ll animate-in and out its path element to show the level of volume. For this, we’ll create a method which switches its CSS class according to the volume level.

<svg @click="changeVolume">
	<g :class="`level-${volumeLevel}`">
		<path d="..."/> <!-- volume level 1 -->
		<path d="..."/> <!-- volume level 2 -->
		<path d="..."/> <!-- volume level 3 -->
		<polygon points="..."/>
	</g>
</svg>

Based on this class, we can show and hide certain path elements as:

path {
	opacity: 0;
	transform-origin: left;
	transform: translateX(-5px) scale(0.6);
	transition: transform 0.25s, opacity 0.2s;
}

.level-1 path:first-child,
.level-2 path:first-child,
.level-2 path:nth-child(2),
.level-3 path {
	opacity: 1;
	transform: none;
}
The animated volume control

Second micro-interaction: The favorite icon

Do you like it when you click on Twitter’s heart button? That’s because it feels unique and special by the way it animates on click. We’ll make something similar but real quick. For this, we first get an SVG heart icon and add it to the the markup. Then we’ll add a bouncy animation to it that’s triggered on click.

@keyframes bounce {
	0%, 100% {
		transform: none;
	}
	30% {
		transform: scale(1.3);
	}
	60% {
		transform: scale(0.9);
	}
}

Another fun thing we can do is add other small heart icons around it with random sizes and positions. Ideally, we’d add a few absolute-positioned HTML elements that a heart as the background. Let’s Arrange each of them as below by setting their left and bottom values.

We’ll also include a fade away effect so the icons appear to dissolve as they move upward by adding a keyframe animation on the same click event.

@keyframes float-upwards {
	0%, 100% {
		opacity: 0;
	}
	50% {
		opacity: 0.7;
	}
	50%, 100% {
		transform: translate(-1px, -5px);
	}
}
The animated favorite button

Summing up

That’s all! I hope you find all this motivating to try animations on your own websites and projects.

While writing this, I also wanted to expand on the fundamental animation principles we glossed over earlier because I believe that they help choose animation durations, and avoid non-meaningful animations. That’s important to discuss because doing animations correctly is better than doing them at all. But this sounds like a whole another topic to be covered in a future article.

The post Writing Animations That Bring Your Site to Life appeared first on CSS-Tricks.

Blobs!

Post pobrano z: Blobs!

I was recently a guest editor for an issue of Bizarro Devs. It’s a great newsletter! Go sign up! I put in a bunch of links around blobs. Like those weird squishy random shapes that are so „in” right now. Here are those links as well. I’m always a fan of publishing stuff I write 😉

Blobs! Blobs are in! Blobs are — ahem — a bit bizarre. I’ll bask in a design like this annual report cover by Matt Pamer all day. I enjoy watching a design trend like this manifest itself in design tooling and become applied in lots of creative and crafty different ways.

We could start with <svg> and draw our own blob using the Pen tool that is pretty much stock in every vector design application. I’m a cheater though, and would probably wind up checking The Noun Project for some blob examples and steal the SVG from there. But sadly, there isn’t much there, at least as far as blobs go.

Thank god for… (wait for it)… THE BLOBMAKER:

Once we have a blob, it’s just begging to be moved around. Monica Dinculescu shows how to do just that with pure CSS and liberal use of various CSS transforms in a keyframe animation:

See the Pen
CSS only morphing blob
by Monica Dinculescu (@notwaldorf)
on CodePen.

Or we can use a JavaScript library like KUTE.js to get all morph-y, like Heartbeat has done here:

See the Pen
Morphing shapes with KUTE.js
by Heartbeat.UA (@hbagency)
on CodePen.

A library like Greensock could help moving and morphing the blobs around. Greensock even has a plugin that is probably the most powerful morphing tool out there. This Pen uses Greensock, but adds some native SVG filters so that the blobs squish into each other satisfyingly. We could call it the gooey effect:

See the Pen
SVG blob mask
by ATCOM (@Atcom)
on CodePen.

We’ve only looked at SVG so far, but don’t rule out <canvas>! Liam Egan has make this canvas-based blob downright jiggly:

See the Pen
Blob
by Liam Egan (@shubniggurath)
on CodePen.

Why not add a little physics to the party, like gravity, and let them blobs get squishy that way! Hakim El Hattab got it done here:

See the Pen
Blob
by Hakim El Hattab (@hakimel)
on CodePen.

And blobs don’t have to be alone! Blobs that are squished together are like fluid. You might get a kick out of Peeke Kuepers article Simulating blobs of fluid.

The post Blobs! appeared first on CSS-Tricks.

Deliver your best work with the help of monday.com

Post pobrano z: Deliver your best work with the help of monday.com

(This is a sponsored post.)

Here’s the situation: You’ve bashed out a complicated design over two weeks of near full-time effort, gotten everything down to the exact spec of the design file, turn it in for stakeholder review and… you’re way off scope. Turns out a few folks on the team put their heads together, made some changes, and never sent you an updated comp.

Boo!

The unfortunate truth is that this happens all too often in front-end development, but it’s really no one person’s fault because it boils down to simple collective miscommunication and a lack of transparency on the team.

Well, that’s where a project management platform like monday.com comes into play. Even if you’re on a remote team or sitting in an office with cubicle walls up to the ceiling, monday.com bridges gaps and tears down walls that could throw a project off-track. With powerful and intuitive tools, like instant messaging for those ad hoc meetings, file storage for a centralized repository of assets, and an activity dashboard for catching up on the status of a project at a glance, monday.com brings project out into the light so everyone is in the loop and on the same page.

Czytaj dalej Deliver your best work with the help of monday.com

Getting to Grips with the Airtable API

Post pobrano z: Getting to Grips with the Airtable API

The Airtable web app is pretty neat. You can use it like a spreadsheet but it’s useful for all sorts of other things too. The neatest thing about it for me is that it has an API so that you can treat it like a database.

I’ve been thinking about making weekly notes for the different teams I work with at Gusto to read about what the design systems team is working on, things we’ve fixed, and any bugs we’ve encountered during that might impact other designers and engineers across our organization. I’ve spent a couple of hours thinking about how we might use Airtable to collect a whole bunch of data and then use its API to extract that info and show it in a web app.

Here’s an example of what we’ll end up building, which is basically a React web app that’s using Airtable as a nifty sorta CMS:

To get started, we have to head on over to the command line and run the following (but first make sure npm is installed):

npx create-react-app airtable-test

This will create a new directory called airtable-test which is where we’ll be making our little React app. If we run yarn start in the command line after that’s finished installing, then we’ll see the default page for the project:

And, if we open up src/App.js in that airtable-test directory, we can see how this page is being rendered with React:

import React, { Component } from 'react';
import logo from './logo.svg';
import './App.css';

class App extends Component {
  render() {
    return (
      <div className="App">
        <header className="App-header">
          <img src={logo} className="App-logo" alt="logo" />
          <p>
            Edit src/App.js and save to reload.
          </p>
          <a
            className="App-link"
            href="https://reactjs.org"
            target="_blank"
            rel="noopener noreferrer"
          >
            Learn React
          
        </header>
      </div>
    );
  }
}

export default App;

Now that we have React up and running, we can go ahead and install airtable in the command line which will let us interact with the Airtable API:

npm i airtable

Once we’ve done that, we’ll need to create an Airtable account and create a project. We should wind up with something like this spreadsheet:

A screenshot of a spreadsheet. The header is a bright orange and the sheet contains four rows and four columns of content, ordered by date.

Now we can then head to airtable.com/api and select our project so that is serves as data we’re pulling from. In this case, I selected “Design Systems Projects” which you can see right at the bottom here:

This will send us to a handy docs website that gives us an incredibly easy to read API for our specific project! Scrolling down we’ll find our API key which we’ll need to access this data as well as a ton of examples that we can use to manipulate the data we get back:

A screenshot of the Airtable API webpage. The heading says Standard API and a list of options, including example projects, is provided. Below the example projects is the project configured in this post, called Design Systems Project.

Let’s head back to App.js in our airtable-test directory, delete all the code in that file, and replace it with the following:

import React, { Component } from 'react';
import Airtable from 'airtable';
const base = new Airtable({ apiKey: 'XXXXXXXXXXX' }).base('XXXXXXXXXXX');

Make sure to replace those Xs with the details that you can see in that Airtable API doc we just opened. But now that we’ve done all the setup, we can finally get around to creating our interface by calling data from our spreadsheet.

In App.js we can start to construct the App component:

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      records: []
    };
  }
  render() {
    return {
      <div className="App">Hello</div>		}
    }
  }
}

All this will do for now is setup the app’s state and then render “Hello” on the page. Next up, we’ll be add each record from Airtable to that state.

First thing that’s important to note below: in componentDidMount() we’ll be selecting Updates which is just a way of telling Airtable that we want the spreadsheet called Updates. Make sure that this name is the same name as the spreadsheet. We’ll also be looping through all the records, or rows, of our table in that function too:

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      records: []
    };
  }
  componentDidMount() {
    base('Updates').select({view: 'Grid view'})
    .eachPage(
      (records, fetchNextPage) => {
        this.setState({
          records
        });
        console.log(records);
        fetchNextPage();
      }
    );
  }
  render() {
    return (
      <div className="App">
        <div>Hello</div>
      </div>
    );
  }
}

fetchNextPage() is the Airtable API’s way of giving us the next record in our spreadsheet and it’s neat that it will keep going until there are no more records. Again, we’re not doing anything with that data yet; we only want to make sure everything is working correctly at this point.

Open up the console in DevTools and we should see something like this:

Array(4) [ {…}, {…}, {…}, {…} ]

And if we dive through each of the objects in this array, then we should find all the data from the spreadsheet! Doing this bit always feels like magic to me.

Anyway, next up we can update our render() function like so:

render() {
  return (
    <div className="App">
      {this.state.records.length > 0 ? (
        this.state.records.map((record, index) =>
          <div key={index}>
            <h2>{record.fields['Date']}</h2>
            {record.fields['UI Kit']}
            {record.fields['Component Library']}
          </div>
        )
        ) : (
          <p>Loading...</p>
        )}
      </div>
    </div>
  );
}

We’re going to be looping through the state that we setup earlier and then rendering the record.fields[] for each column in our spreadsheet. We have a Date, UI Kit, and Component Library column, and once we’ve updated our App.js with the code above, we should see all the content from our spreadsheet!

A screenshot of a default webpage with no styling with four headings containing dates in year/month/day numeric format following by a block of text containing content from the spreadsheet.

It’s like magic! But why does this data look so weird? Well, it’s because I wanted to write Markdown in each cell, so now we’ll need to use a parser to convert that data into good ol’ fashioned HTML. First, we need to head back to the command line though:

npm i showdown 

showdown will help us parse all that Markdown we’ve written in our Airtable spreadsheet. After installing it, we only need to import it at the top of our App.js file, like this:

import showdown from 'showdown';
const markdownConverter = new showdown.Converter();

After the componentDidMount() function, we can create another function that will create our HTML using showdown:

createHTML(markdown){
  return(
    markdownConverter.makeHtml(markdown)
  )
}

It’s a little iffy, but it makes me feel like the code is a bit tidier this way. Now we can update our render() function:

  render() {
  return (
    <div className="App">
      {this.state.records.length > 0 ? (
        this.state.records.map((record, index) =>
          <div key={index}>
            <h2>{new Date(record.fields['Date']).toISOString().split('T', 1)}</h2>
            <div dangerouslySetInnerHTML={{__html: this.createHTML(record.fields['UI Kit'])}} />
            <div dangerouslySetInnerHTML={{__html: this.createHTML(record.fields['Component Library'])}} />
          </div>
        )
      ) : (
        <p>Loading...</p>
      )}
    </div>
  );
}

We’re doing a couple of new things here: we’re using dangerouslySetInnerHTML in each div which, in turn, uses our createHTML function to convert the data from each column (specifically, the UI Kit and Component Library columns). We’re also converting the dates of each row into headings to make things a bit easier to read.

And with that we’re pretty much done! Here’s the final App.js:

import React, { Component } from 'react';
import Airtable from 'airtable';
import showdown from 'showdown';

const markdownConverter = new showdown.Converter();

const base = new Airtable({ apiKey: 'xxxxxxx' }).base('xxxxxxx');

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      records: []
    };
  }
  componentDidMount() {
    base('Updates').select({view: 'Grid view'})
    .eachPage(
      (records, fetchNextPage) => {
        this.setState({
          records
        });
        fetchNextPage();
      }
    );
  }
  createHTML(markdown){
    return(
      markdownConverter.makeHtml(markdown)
    )
  }
  render() {
    return (
      <div className="App">
        {this.state.records.length > 0 ? (
          this.state.records.map((record, index) =>
            <div key={index}>
              <h2>{new Date(record.fields['Date']).toISOString().split('T', 1)}</h2>
              <div dangerouslySetInnerHTML={{__html: this.createHTML(record.fields['UI Kit'])}} />
              <div dangerouslySetInnerHTML={{__html: this.createHTML(record.fields['Component Library'])}} />
            </div>
          )
        ) : (
          <p>Loading...</p>
        )}
      </div>
    );
  }
}

export default App;

There’s still a ton of updates we could make to improve things. I took a first pass at styling, but we probably want to do things like improve the date format and maybe have some kind of indication as to which updates refer to which rows in the spreadsheet. Maybe we could even toggle showing which information to show depending on whether you’re a designer or engineer.

An animating screenshot of the final result which contains the same content as the earlier example but with extra spacing between sections and the column headings in dark orange and flushed to the left of the content instead of above it.

Anyway! I think this is a good start to getting to grips with the Airtable API and I’d love to hear about how you use it in the comments below.

The post Getting to Grips with the Airtable API appeared first on CSS-Tricks.