Reactive Timeframe Concept

index.html

<input type="checkbox" id="switch" />
<div id="app">
  <header class="ui-header">
    <i class="fa fa-chevron-left"></i>
    <div class="ui-text -app-title">App Settings</div>
    <div class="ui-text">Apply</div>
  </header>
  <main class="ui-content">
    <div class="ui-discounts">
      <i class="fa fa-codepen"></i>
      <div class="ui-text">Get hottest discounts</div>
    </div>
    <div class="ui-value">
      <div class="ui-digit" id="num1"></div>
      <div class="ui-digit" id="num2"></div>
    </div>
    <div class="ui-panel">
      <div class="ui-range-ticks">
        <div class="ui-range-tick" data-value="0"></div>
        <div class="ui-range-tick" data-value="3"></div>
        <div class="ui-range-tick" data-value="6"></div>
        <div class="ui-range-tick" data-value="9"></div>
        <div class="ui-range-tick" data-value="12"></div>
      </div>
      <div class="ui-range" id="rangeTrack">
        <input
          type="range"
          id="range"
          class="ui-range-input"
          min="0"
          max="12"
          step="1"
          value="6"
        />
        <div class="ui-range-track">
          <div class="ui-range-thumb"></div>
        </div>
      </div>
      
      <div class="ui-controls">
        <div class="ui-switch">
          <label
            class="ui-switch-track"
            for="switch"
            title="Turn smooth range thumb on/off"
          >
          </label>
        </div>
      </div>
      
      <div class="ui-footer">
        <i class="fa fa-shopping-bag"></i>
        <i class="fa fa-cart-arrow-down"></i>
        <i class="fa fa-filter"></i>
        <i class="fa fa-gear"></i>
      </div>
    </div>
  </main>
</div>

reactive-timeframe-concept.markdown

Reactive Timeframe Concept

Based on a Dribbble by Stan Yakusevich. Drag the range thumb to see the effect.

Works best on Chrome (desktop and mobile), and Safari on iPad (oddly enough). Works decently in Firefox, but only because I added a fallback. Click the switch to reveal the real HTML5 range input.

A Pen by David Khourshid on CodePen.

License.

script.babel

const range = document.querySelector('#range');
const rangeTrack = document.querySelector('#rangeTrack');
const value = document.querySelector('.ui-value');
const num1 = document.querySelector('#num1');
const num2 = document.querySelector('#num2');
const ticks = document.querySelectorAll('.ui-range-tick');
const docStyle = document.documentElement.style;

const { fromEvent, interval } = Rx.Observable;

const clamp = (min, max) => val => Math.min(Math.max(val, min), max);

const lerp = (curr, next) => {
  const delta = (next - curr);
  if (Math.abs(delta) < 0.01) return curr;
  return curr + (next - curr) * 0.13;
};

const touch$ = fromEvent(range, 'input');

const touchEnd$ = fromEvent(range, 'mouseup')
  .merge(fromEvent(range, 'touchend'))
  .mapTo(false);

const change$ = touch$
  .mapTo(true)
  .merge(touchEnd$)
  .distinctUntilChanged();
  
const num$ = touch$
  .map(e => +e.target.value)
  .distinctUntilChanged()
  .startWith(6);

const af$ = interval(0, Rx.Scheduler.animationFrame);

const smoothNum$ = af$
  .withLatestFrom(num$, (_, num) => num)
  .scan(lerp)
  .distinctUntilChanged();

const progress$ = smoothNum$
  .map(num => num - Math.floor(num));

smoothNum$.subscribe(num => {
  num1.innerHTML = Math.floor(num);
  num2.innerHTML = Math.ceil(num);
  docStyle.setProperty('--value', num);

  Array.from(ticks).forEach((tick) => {
    const proximity = Math.min(
      Math.abs(tick.getAttribute('data-value') - num), 2);
    tick.style.setProperty('--proximity', proximity);
  });
});

progress$.subscribe(progress => {
  docStyle.setProperty('--progress', progress);
  
  if (navigator.userAgent.toLowerCase().indexOf('firefox') > -1) {
    // Firefox does not support custom properties
    // inside of scale() for whatever reason
    num1.setAttribute('style', `
      transform:
        translateX(calc(${progress} * -10vh))
        scale(${1 + progress});
      opacity: ${1 - progress};

    `);
    
    num2.setAttribute('style', `
      transform:
        translateX(calc(${progress} * -10vh + 10vh))
        scale(${progress});
      opacity: ${progress};
    `);
  }
});

change$.subscribe(changing => {
  num1.parentElement.style.setProperty('--changing', +changing);
});

scripts

<script src="https://unpkg.com/@reactivex/rxjs@5.1.1/dist/global/Rx.min.js"></script>

style.scss

@import url('https://fonts.googleapis.com/css?family=Open+Sans:300,700');

$max-value: 12;
$num-shift: 10vh;
$num-size: 24vh;
$start-value: 6;

$color-gray: #B5B5B5;

:root {
  --value-progress: calc(var(--value, #{$start-value}) / #{$max-value});
  font-family: Open Sans, sans-serif;
  font-weight: 300;
  font-size: 2.5vh;
}

#app {
  height: 96vh;
  width: 54vh;
  background: linear-gradient(
    to top right,
    hsl(360, 90%, 68%),
    hsl(31, 100%, 51%),
    #EC4E91,
    #9535D3,
    #4DACFF
  );
  background-size: 400% 400%;
  background-position: calc(var(--value-progress) * 100%) 0;
  color: white;
  user-select: none;
  overflow: hidden;
  box-shadow: 0 0 4vh rgba(black, 0.1);
  
  @media
    (max-width: 740px)
    and (-webkit-min-device-pixel-ratio: 2)
    and (orientation: portrait) {
    width: 100%;
    height: 100%;
  }
}

$header-height: 8vh;
.ui-header {
  height: $header-height;
  width: 100%;
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  align-items: center;
  padding: 2vh;
  background: white;
  color: $color-gray;
  
  > * {
    width: 25%;
    flex: 0 0 25%;
  }
  
  > .ui-text.-app-title {
    text-align: center;
    flex: 1 0 auto;
    white-space: nowrap;
  }
  
  > .ui-text:last-child {
    text-align: right;
  }
}

.ui-content {
  flex: 1 0 100%;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  padding-top: $header-height;
}

.ui-discounts {
  padding: 2vh 0;
  text-align: center;
  width: calc(100% - 6vh);
  margin: 0 2vh;
  border-bottom: 1px solid rgba(white, 0.25);
  
  > .ui-text {
    margin: 1vh 0;
    line-height: 1;
    letter-spacing: 0.5px;
  }
}

.ui-value {
  height: $num-size;
  width: $num-size * 1.2;
  line-height: $num-size;
  margin: 2vh 0;
  font-weight: 700;
  
  &:before, &:after {
    display: block;
    position: absolute;
    height: 4vh;
    line-height: 4vh;
    top: calc(50% - 2vh);
    font-weight: 300;
    font-size: 2.5vh;
    letter-spacing: 0.5px;
    transition: transform 0.6s ease;
  }
  &:before {
    content: 'Every';
    right: 100%;
    transform: translateX(calc(var(--changing) * -50%));
  }
  &:after {
    content: 'hours';
    left: 100%;
    transform: translateX(calc(var(--changing) * 50%));
  }
}

.ui-digit {
  position: absolute;
  font-size: $num-size;
  width: 100%;
  text-align: center;
  height: 100%;
  user-select: none;
}

#num1 {
  transform:
    translateX(calc(var(--progress, 0) * -#{$num-shift}))
    scale(calc(1 + var(--progress, 0)));
  opacity: calc(1 - var(--progress, 0));
  filter: blur(calc(var(--progress) * 2px));
}

#num2 {
  transform:
    translateX(calc(var(--progress, 0) * -#{$num-shift} + #{$num-shift}))
    scale(calc(var(--progress, 0)));
  opacity: var(--progress, 0);
}

.ui-panel {
  width: 100%;
}

.ui-controls {
  background: white;
  padding: 6vh 4vh;
}

.ui-switch {
  margin: 0 auto;
  top: 2vh;
  width: 8vh;
  height: 4vh;
  border-radius: 4vh;
  background-image: linear-gradient(
    to right,
    #FF6850,
    #FF8A2B
  );
  
  &:before, &:after {
    position: absolute;
    color: #656565;
    margin: 0 2vh;
    height: 2vh;
    top: calc(50% - 1vh);
    display: block;
    font-size: 2vh;
    line-height: 2vh;
    letter-spacing: 0.5px;
  }
  &:before {
    content: 'Off';
    right: 100%;
  }
  &:after {
    content: 'On';
    left: 100%;
  }
}

input#switch {
  position: absolute;
  opacity: 0;
  pointer-events: none;

  &:checked + #app {
    * {
      .ui-switch-track {
        transform: translateX(-2vh) scale(0.8);
      }

      .ui-range-track {
        display: none;
      }
    }
  }
  
  &:not(:checked) + #app {
    --thumb-opacity: 0;
  }
}

.ui-switch-track {
  position: absolute;
  top: 0;
  left: calc(50% - 2vh);
  width: 4vh;
  height: 4vh;
  border-radius: 50%;
  border: 0.5vh solid rgba(white, 0.1);
  background: white;
  display: block;
  transform: translateX(2vh) scale(0.8);
  transition: transform 0.3s ease;
  box-shadow: 0 0 1vh rgba(black, 0.1);
}

.ui-range {
  width: 100%;
  background: white;
  z-index: 1;
  
  > input {
    position: absolute;
    z-index: 1;
    top: -3vh;
  }
}

.ui-range-track {
  position: absolute;
  top: 1vh;
  width: calc(100% - 8vh);
  transform:
    translateX(calc(var(--value, #{$start-value}) / 12 * 100% - 50%));
  left: 4vh;
  z-index: 1;
  pointer-events: none;
  
  &:before, &:after {
    content: '';
    position: absolute;
    width: 8vh;
    height: 8vh;
    border-radius: 50%;
    top: -4vh;
    left: calc(50% - 4vh);
    background: white;
  }
  
  &:before {
    transform: scale(1.2);
  }
  
  &:after {
    content: "\f1cb";
    font-family: FontAwesome;
    font-size: 4vh;
    line-height: 8vh;
    color: #FF6850;
    text-align: center;
    top: -4vh;
    box-shadow: 0 0.5vh 2vh 0.5vh rgba(black, 0.1);
  }
}

.ui-range-ticks {
  width: 100%;
  height: 3vh;
  margin-bottom: 6vh;
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  padding: 0 2vh;
}

.ui-range-tick {
  width: 4vh;
  transform:
    translateY(calc(var(--proximity) * 1vh - 1vh));
  
  &:before {
    content: attr(data-value);
    display: block;
    width: 100%;
    text-align: center;
    transform: scale(calc((2 - var(--proximity)) / 3 + 1));
    transform-origin: bottom center;
  }
  &:after {
    content: '';
    position: absolute;
    display: block;
    width: 1px;
    height: 1vh;
    background: white;
    left: calc(50% - 0.5px);
    top: calc(100% + 1vh);
    transform: translateY(calc(var(--proximity) * 0.5vh - 0.5vh));
  }
}

.ui-footer {
  color: $color-gray;
  background: white;
  padding: 1rem 0;
  display: flex;
  flex-direction: row;
  justify-content: space-around;
  align-items: center;
  box-shadow: 0 -0.5rem 1rem rgba(gray, 0.1);
  z-index: 1;
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
  background-image: linear-gradient(to bottom right, white, #E7E7EF);
}

html, body {
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0;
}

svg {
  display: none;
}

*, *:before, *:after {
  box-sizing: border-box;
  position: relative;
}



// source: https://css-tricks.com/styling-cross-browser-compatible-range-inputs-css/
// thanks, @danieljackstern !!
$track-color: #EFEFEF !default;
$thumb-color: white !default;

$thumb-radius: 8vh !default;
$thumb-height: 8vh !default;
$thumb-width: 8vh !default;
$thumb-shadow-size: 4px !default;
$thumb-shadow-blur: 0.5vh !default;
$thumb-shadow-color: rgba(black, 0.1) !default;
$thumb-border-width: 0 !default;
$thumb-border-color: #eceff1 !default;

$track-width: 100% !default;
$track-height: 1px !default;
$track-shadow-size: 0 !default;
$track-shadow-blur: 0 !default;
$track-shadow-color: rgba(0, 0, 0, .2) !default;

$track-radius: 0 !default;
$contrast: 5% !default;

@mixin shadow($shadow-size, $shadow-blur, $shadow-color) {
  box-shadow: $shadow-size $shadow-size $shadow-blur $shadow-color, 0 0 $shadow-size lighten($shadow-color, 5%);
}

@mixin track {
  cursor: pointer;
  height: $track-height;
  transition: all .2s ease;
  width: $track-width;
  opacity: --thumb-opacity;
}

@mixin thumb {
  box-shadow: 0 0.5vh 2vh 0.5vh rgba(black, 0.1);
  background: $thumb-color;
  border: $thumb-border-width solid $thumb-border-color;
  border-radius: $thumb-radius;
  cursor: pointer;
  height: $thumb-height;
  width: $thumb-width;
  opacity: var(--thumb-opacity, 1);
}

[type='range'] {
  -webkit-appearance: none;
  margin: $thumb-height / 2 0;
  width: $track-width;

  &:focus {
    outline: 0;

    &::-webkit-slider-runnable-track {
      background: lighten($track-color, $contrast);
    }

    &::-ms-fill-lower {
      background: $track-color;
    }

    &::-ms-fill-upper {
      background: lighten($track-color, $contrast);
    }
  }

  &::-webkit-slider-runnable-track {
    @include track;
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: $track-color;
  }

  &::-webkit-slider-thumb {
    @include thumb;
    -webkit-appearance: none;
    margin-top: calc(#{$track-height / 2} - #{$thumb-height / 2});
  }

  &::-moz-range-track {
    @include track;
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: $track-color;
  }

  &::-moz-range-thumb {
    @include thumb;
  }

  &::-ms-track {
    @include track;
    background: transparent;
    border-color: transparent;
    border-width: ($thumb-height / 2) 0;
    color: transparent;
  }

  &::-ms-fill-lower {
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: darken($track-color, $contrast);
  }

  &::-ms-fill-upper {
    @include shadow($track-shadow-size, $track-shadow-blur, $track-shadow-color);
    background: $track-color;
  }

  &::-ms-thumb {
    @include thumb;
    margin-top: 0;
  }
}