Vue

Animating

Sarah Drasner

@sarah_edo

Consultant

CSS-Tricks, IBM, Microsoft, Salesforce
Smashing Magazine, NetMag, Zillow, Workflo,
O’Reilly, Frontend Masters, & Mule Design

      Microsoft

Sr. Cloud
Developer Advocate

Why Animate?

Our story starts with performance.

The "so what" factor

User attention span is short.

2 seconds

until dropoff

Amazon has discovered that for every one second delay, conversions dropped by 7%. If you sell $100k per day, that’s an annual loss of $2.5m.

Walmart has found that it gains 1% revenue increase for every 100ms of improvement.

Over 4 seconds: HORROR

Perceived Performance

Humans over-estimate passive waits by 36% - Eli Fitch and Richard Larson, MIT

Your benchmarks aren't telling you the full story.

Custom Experience:

Viget did an experiment and found that despite some individual variation, novel loaders as a whole had a higher wait time and lower abandon rate than generic ones

22 sec

14 sec

Creating Spatial Awareness

Saccade

“We’ve evolved to perform actions that flow more or less seamlessly.

 

"We aren’t wired to deal with the fits and starts of human-computer interaction.”

Sensory memory: Your occipital lobe (AKA “the memory store”) works in 100ms bursts.

-Tammy Everts

Gain understanding

Spatial or otherwise

Without Transitions

Paul Bakaus

Morphing

From this CSS-Tricks Article

this pen.

So Many Ways!

  • How to work with Vue
  • <transition /> component
  • Watchers/Reactivity
  • SVG!
  • Coordinating state with Vuex/ lifecycle methods
  • Animations via custom directives
  • Nuxt, server-side rendering, and page transitions

Vue Basics

Tiny Comparison

  • A Virtual DOM
  • Reactive components that offer the View layer only
  • Props and a Redux-like store similar to React.
  • Conditional rendering, and services, similar to Angular.
  • Inspired by Polymer for simplicity and performance, Vue allows you to create HTML, CSS, and JS in tandem.

see the comparison

Hello World!

Obligatory Example

<div id="app">{{ text }} Nice to meet Vue.</div>

Light Comparison:

Vanilla JS vs Vue for Conditional Rendering

Vanilla JS

const items = [
  'thingie',
  'another thingie',
  'lots of stuff',
  'yadda yadda'
];
function listOfStuff() {
  let full_list = '';
  for (let i = 0; i < items.length; i++) {
      full_list = full_list + `<li> ${items[i]} </li>`
  }
  const contain = document.querySelector('#container');
  contain.innerHTML = `<ul> ${full_list} </ul>`;     
}
listOfStuff();

HTML:

<div id="container"></div>

yields:

This pen

Vue

new Vue({
  el: '#app',
  data: {
    items: [
      'thingie',
      'another thingie',
      'lots of stuff',
      'yadda yadda'
    ]
  }
});
<div id="app">
  <ul>
    <li v-for="item in items">
      {{ item }}
    </li>
  </ul>
</div>

yields:

This pen

  • clean
  • semantic
  • declarative
  • legible
  • easy to maintain
  • reactive

V-Model

Creates a relationship between the data in the instance/component and a form input, so you can dynamically update values

Accepting user input and managing it in a responsible manner

new Vue({
  el: '#app',
  data() {
    return {
      message: 'This is a good place to type things.'  
    }
  }
});
<div id="app">
  <h3>Type here:</h3>
  <textarea v-model="message" class="message" rows="5" maxlength="72"/>
  <br>
  <p class="booktext">{{ message }} </p>
</div>

This pen.

🏆

<Transition />

  <app-child v-if="isShowing" class="modal">
    <button @click="toggleShow">
      Close
    </button>
  </app-child>
new Vue({
  el: '#app',
  data() {
    return {
      isShowing: false
    }
  },
  methods: {
    toggleShow() {
      this.isShowing = !this.isShowing;
    }
  }
});

This pen.

😳

<transition name="fade">
  <app-child v-if="isShowing" class="modal">
    <button @click="toggleShow">
      Close
    </button>
  </app-child>
</transition>

  <app-child v-if="isShowing" class="modal">
    <button @click="toggleShow">
      Close
    </button>
  </app-child>

Transition Component

Encapsulate what is changing declaratively

Vue Elegance

Default 'v-' prefix, otherwise name="foo"

Example:

.v-enter-active {
  transition: color 1s ease;
}
.fade-enter-active, .fade-leave-active {
  transition: opacity 0.25s ease-out;
}

.fade-enter, .fade-leave-to {
  opacity: 0;
}

Reusable for other components

This pen.

Great!

But...

<div :class="[isShowing ? blurClass : '', bkClass]">
  <h3>Let's trigger this here modal!</h3>
  <button @click="toggleShow">
    <span v-if="isShowing">Hide child</span>
    <span v-else>Show child</span>
  </button>
</div>
.bk {
  transition: all 0.05s ease-out;
}

.blur {
  filter: blur(2px);
  opacity: 0.4;
}

This pen.

Transition Modes

🏆

🏆

This pen

Without transition modes

The current element waits until the new element is done transitioning in to fire

 

 

 

 

The current element transitions out and then the new element transitions in.

In-out

Out-in

<transition name="flip" mode="out-in">
  <slot v-if="!isShowing"></slot>
  <img v-else src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/28963/cartoonvideo14.jpeg" />
</transition>

HTML

CSS Animation

enter-active-class="toasty"
leave-active-class="bounceOut"

Still <transition /> component, but

This pen.

  <transition
    enter-active-class="bouncein"
    leave-active-class="rollout">
    <div v-if="isShowing">
      <app-child class="child"></app-child>
    </div>
  </transition>

Bounce a ball

@mixin ballb($yaxis: 0) {
  transform: translate3d(0, $yaxis, 0);
}

@keyframes bouncein { 
  1% { @include ballb(-400px); }
  20%, 40%, 60%, 80%, 95%, 99%, 100% { @include ballb() }
  30% { @include ballb(-80px); }
  50% { @include ballb(-40px); }
  70% { @include ballb(-30px); }
  90% { @include ballb(-15px); }
  97% { @include ballb(-10px); }
}

.bouncein { 
  animation: bouncein 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94) both;
}

.ballmove-enter {
  @include ballb(-400px);
}

Keep it DRY

JavaScript Hooks

<transition 
  @before-enter="beforeEnter"
  @enter="enter"
  @after-enter="afterEnter"
  @enter-cancelled="enterCancelled"

  @before-leave="beforeLeave"
  @leave="leave"
  @after-leave="afterLeave"
  @leave-cancelled="leaveCancelled"
  :css="false">
 
 </transition>

Custom Naming

<transition 
  @enter="enterEl"
  @leave="leaveEl"
  :css="false">
  <!-- put element here-->
 </transition>

Most Basic Example

methods: {
   enterEl(el, done) {
     //entrance animation
     done();
  },
  leaveEl(el, done) {
    //exit animation
    done();
  },
}

Most Basic Example

This pen.

<transition @before-enter="beforeEnter" @enter="enter" :css="false">
  <p class="booktext" v-if="load">
    {{ message }}
  </p>
</transition>
new Vue({
  ...
  methods: {
    beforeEnter(el) {
      TweenMax.set(el, {
        transformPerspective: 600,
        perspective: 300,
        transformStyle: "preserve-3d",
        autoAlpha: 1
      });
    },
    enter(el, done) {
      tl.add("drop");
      for (var i = 0; i < wordCount; i++) {
        tl.from(split.words[i], 1.5, {
          z: Math.floor(Math.random() * (1 + 150 - -150) + -150),
          ease: Bounce.easeOut
        }, "drop+=0." + (i/ 0.5));
       ...
    }
  }
});
let tl = new TimelineMax({ onComplete: done });

onComplete: done

done();

or

<TransitionGroup />

FLIP, with no heavy lifting!

FLIP stands for First, Last, Invert, Play

Rosario's article

 <transition-group name="cell" tag="div" class="container">
    <div v-for="cell in cells" :key="cell.id">
      {{ cell.number }}
    </div>
  </transition-group>

From the guide

Leverage the Reactivity System for Transitions

Watchers

& Vue's Reactivity System

What is Reactive?

Reactive programming is programming with asynchronous data streams.

A stream is a sequence of ongoing events ordered in time that offer some hooks with which to observe it.

When we use reactive premises for building applications, this means it's very easy to update state in reaction to events.

What is Reactive?

 

  • Angular 1.x has dirty checking.
  • Cycle.js and Angular 2 use reactive streams like XStream and Rx.js.
  • Vue.js, MobX or Ractive.js all use a variation of getters/setters.

More Resources:

Despite the name, React is not Reactive- it uses a "pull" approach (rather than "push")

Watchers

Good for asynchronous updates,

and updates/transitions with data changes

We're going to 'watch' any data property declared on the Vue instance

State change can create the animation

SVG is good for this because it's built with MATH

SVG!

Built with math

<!--xaxis -->
<g targetVal="targetVal"  class="xaxis">
  <line x1="0" y1="1" x2="350" y2="1"/>
  <g v-for="(select, index) in targetVal">
    <line y1="0" y2="7" v-bind="{ 'x1':index*10, 'x2':index*10 }"/>
    <text v-if="index % 5 === 0" v-bind="{ 'x':index*10, 'y':20 }">{{ index }}</text>
  </g>
</g>

Interpolation with style bindings- this pen

In the instance:

new Vue({
  el: '#app',
  data() {
    return {
      x: 0, 
      y: 0
    }
  },
  methods: {
    coords(e) {
      this.x = e.clientX / 10;
      this.y = e.clientY / 10;
    },
  }
})

In the template:

<div id="contain" :style="{ perspectiveOrigin: `${x}% ${y}%` }">

SVG Animation

Vue.js

=

🔥

+

Personality

Emotions are tied to your limbic system and easier to remember

This pen.

<div id="app" @mousemove="coordinates">
coordinates(e) {
  const audio = new Audio('https://s3-us-west-2.amazonaws.com/s.cdpn.io/28963/Whoa.mp3'),
    walleBox = document.getElementById('walle').getBoundingClientRect(),
    walleCoords = walleBox.width / 2 + walleBox.left;
    ...

    TweenMax.set("#eyes", {
      scaleX: 1 + (1 - e.clientX / walleCoords) / 5
    });
    TweenMax.set("#walle", {
      x: ((e.clientX / walleCoords) * 50) - 40
    });

    this.startArms.progress(1 - (e.clientX / walleCoords)).pause();
  }
},

In <template>

In Vue Instance

clipPath- great support

This pen.

createBigCircles() {
  const svgNS = this.$refs.figure.namespaceURI;
  this.$refs.patterngroup.innerHTML = '';
  
  for (let i = 0; i < this.numLines/2; i++) {
    let circ = document.createElementNS(svgNS, 'circle');
    this.append(this.$refs.patterngroup, circ);
    this.setAttributes(circ, {
      'cx': this.size/2,
      'cy': this.size/2,
      'r': this.totesRando(this.size/2, 0),
      'fill': 'none',
      'stroke': this.gradients2[this.totesRando(1, 0)],
      'stroke-width': 1
    });
  }
},
<div class="formarea">
  <h3>Create Circles:</h3>
  <button @click="createSmCircles">Make small circles</button>
  <button @click="createBigCircles">Make big circles</button>
</div>

Coordinating Transitions

End to end

Encapsulate what is changing - repo

State-driven animation

Encapsulate what is changing- Vuex

export const store = new Vuex.Store({
  state: {
    showWeather: false,
    template: 0
  },
  mutations: {
    toggle: state => state.showWeather = !state.showWeather,
    updateTemplate: (state) => {
      state.showWeather = !state.showWeather;
      state.template = (state.template + 1) % 4;
    }
  }
});
<transition @leave="leaveDialog" :css="false">
  <app-dialog v-if="showWeather"></app-dialog>
</transition>
<transition @leave="leaveDroparea" :css="false">
  <g v-if="showWeather">
    <app-droparea v-if="template == 1"></app-droparea>
    <app-windarea v-else-if="template == 2"></app-windarea>
    <app-rainbowarea v-else-if="template == 3"></app-rainbowarea>
    <app-tornadoarea v-else></app-tornadoarea>
  </g>
</transition>
export default {
  computed: {
    template() {
      return this.$store.state.template;
    }
  },
  methods: {
    toggle() {
      this.$store.commit('toggle');
    }
  },
  mounted() {
    //enter weather
    const tl = new TimelineMax();
    tl.add("enter");
    tl.fromTo("#dialog", 2, {
      opacity: 0
    }, {
      opacity: 1
    }, "enter");
    tl.fromTo("#dialog", 2, {
      rotation: -4
    }, {
      rotation: 0,
      transformOrigin: "50% 100%",
      ease: Elastic.easeOut
    }, "enter");
  }
}

Lifecycle hooks

This pen.

const Child = {
  beforeCreate() {
    console.log("beforeCreate!");
  }, 
  ...
};

Custom Directives

Vue.directive('tack', {
 bind(el, binding, vnode) {
    el.style.position = 'fixed'
  }
});
<p v-tack>I will now be tacked onto the page</p>

😳

Vue.directive('tack', {
  bind(el, binding, vnode) {
    el.style.position = 'fixed'
    el.style.top = binding.value + 'px'
  }
});
<div id="app">
  <p>Scroll down the page</p>
  <p v-tack="70">Stick me 70px from the top of the page</p>
</div>

🙂

Vue.directive('tack', {
  bind(el, binding, vnode) {
    el.style.position = 'fixed';
    const s = (binding.arg == 'left' ? 'left' : 'top');
    el.style[s] = binding.value + 'px';
  }
});
<p v-tack:left="70">I'll now be offset from the left instead of the top</p>

😊

Pass an argument

Vue.directive('tack', {
  bind(el, binding, vnode) {
    el.style.position = 'fixed';
    el.style.top = binding.value.top + 'px';
    el.style.left = binding.value.left + 'px';
  }
}); 
<p v-tack="{ top: '40', left: '100' }">Stick me 40px from the top of the
page and 100px from the left of the page</p>

😃

More than one value

Let's apply this to Animation

Vue.directive('scroll', {
  inserted: function(el, binding) {
    let f = function(evt) {
      if (binding.value(evt, el)) {
        window.removeEventListener('scroll', f);
      }
    };
    window.addEventListener('scroll', f);
  },
});

// main app
new Vue({
  el: '#app',
  methods: {
   handleScroll: function(evt, el) {
    if (window.scrollY > 50) {
      TweenMax.to(el, 1.5, {
        y: -10,
        opacity: 1,
        ease: Sine.easeOut
      })
    }
    return window.scrollY > 100;
    }
  }
});
<div class="box" v-scroll="handleScroll">
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. A atque amet harum aut ab veritatis earum porro praesentium ut corporis. Quasi provident dolorem officia iure fugiat, eius mollitia sequi quisquam.</p>
</div>

🔥

Custom Directives + D3

export default {
    methods: {
      totalImpact: function(evt, el) {
        if (window.scrollY > 1100) {
          TweenMax.to(el, 0.75, {
            opacity: 0
          })
          let circ =  d3.selectAll("circle")
                      .attr("cx", function(d) {
                        let lat = d["Longitude (Deg)"];
                        if (lat.includes("E")) {
                          return midX - parseInt(lat) * incByW;
                        } else {
                          return midX + (parseInt(lat) * incByW);
                        }
                      })
                      ...
                      .attr("r", 5)
                      .attr("fill", "url(#radgrad)")
        }
        return window.scrollY > 1300;
      },

Update the circle's coordinates

<div class="box accelerate impact" v-dscroll="totalImpact">
  <h3>Total Impact</h3>
  <p>Most alksdjflkjasd laksdjfl;kasjdf laksd falksdjf lsdj f</p>
</div>

Nuxt Routing & Page Transitions

Server Side Rendering

By rendering on the server, you can cache the final shape of your data

"

"

-Karl Seguin

npm install -g vue-cli

--------
 
vue init nuxt/starter my-project
cd my-project
yarn
 
npm run dev

Templates in the pages directory

<nuxt-link to="/product">Product</nuxt link>

Transition hook already available

name="page"
.page-enter-active, .page-leave-active {
  transition: all .25s ease-out;
}
.page-enter, .page-leave-active {
  opacity: 0;
  transform: scale(0.95);
  transform-origin: 50% 50%;
}

🏆

Animation as well

.page-enter-active {
  animation: acrossIn .45s ease-out both;
} 
 
.page-leave-active {
  animation: acrossOut .65s ease-in both;
} 

JS Hooks

export default {
  transition: {
    mode: 'out-in',
    css: false,
    enter (el, done) {

      let tl = new TimelineMax({ onComplete: done }),
          spt = new SplitText('h1', {type: 'chars' }), 
          chars = spt.chars;

      TweenMax.set(chars, {
        transformPerspective: 600,
        perspective: 300,
        transformStyle: 'preserve-3d'
      })

      tl.add('start')
      tl.from(el, 0.8, {
        scale: 0.9,
        transformOrigin: '50% 50%',
        ease: Sine.easeOut
      }, 'start')
      ...
      tl.timeScale(1.5)
    }
  ...

Single element

Three.js

<div id="container"></div>

Call on mounted

mounted() {
  //we have to load the texture when it's mounted and pass it in
  let earthmap = THREE.ImageUtils.loadTexture('/world7.jpg');
  this.initGlobe(earthmap);
}
//from
const geometry = new THREE.SphereGeometry(200, 40, 30);
//to 
const geometry = new THREE.IcosahedronGeometry(200, 0);

Vue

makes it extraordinarily intuitive 

to create complex and beautiful interactions

that feel seamless for our users.

We can connect states and reduce cognitive load for things that are changing in our application with ease.

Avoid burnout.

Have fun.

Thank you!

@sarah_edo on twitter

These slides:

slides.com/sdrasner/animating-vue-e17

Animating Vue II

By sdrasner

Animating Vue II

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