amp-bind

<p [text]="'Hello ' + foo">Hello World</p>

<button on="tap:AMP.setState({foo: 'Interactivity'})">
  Say "Hello Interactivity"
</button>

<amp-state id="myDefinedState">
  <script type="application/json">
    {
      "foo": "bar"
    }
  </script>
</amp-state>
<p [text]="myDefinedState.foo"></p>
<button on="tap:AMP.setState({})">See value of initialized state</button>

<amp-state id="myUpdateState">
  <script type="application/json">
    {
      "foo": "bar",
      "baz": "hello"
    }
  </script>
</amp-state>
<p [text]="myUpdateState.foo"></p>
<p [text]="myUpdateState.baz"></p>
<button on="tap:AMP.setState({})">See value of set state</button>
<!-- Like JavaScript, you can reference existing
     variables in the values of the  object literal. -->
<button on="tap:AMP.setState({myUpdateState:{baz: myUpdateState.foo}})">
  Set value of baz to value of foo
</button>
<button on="tap:AMP.setState({myUpdateState:{baz: 'world'}})">
  Set value of baz to "world"
</button>

<!-- The "change" event of this <input> element contains
     a "value" variable that can be referenced via "event.value". -->
<select on="change:AMP.setState({ option: event.value })">
  <option value="0">No selection</option>
  <option value="1">Option 1</option>
  <option value="2">Option 2</option>
</select>
<div hidden [hidden]="option != 1">
  Option 1
</div>
<div hidden [hidden]="option != 2">
  Option 2
</div>

<amp-state id="myState">
  <script type="application/json">
    {
      "foo": "bar",
      "first": {
        "a": "nested once",
        "ab": {
          "b": "nested twice",
          "bc": {
            "c": "nested three times",
            "cd": {
              "d": "nested four times",
              "de": {
                "e": "nested five times",
                "ef": {
                  "f": "nested six times",
                  "fg": {
                    "g": "nested seven times",
                    "gh": {
                      "h": "nested nine times",
                      "hi": {
                        "i": "nested ten times"
                      }
                    }
                  }
                }
              }
            }
          }
        }
      }
    }
  </script>
</amp-state>
<p [text]="myState.foo"></p>
<p [text]="myState.first.ab.bc.cd.de.ef.fg.gh.hi.i"></p>
<button on="tap:AMP.setState({})">See value of set state</button>
<button
  on="tap:AMP.setState({ myState: {first: {ab: {bc: {cd: {de: {ef: {fg: {gh: {hi: {i:'this is as far as you should merge nested values'} } } } } } } } } } })"
>
  Merge 10th nested object
</button>

<p [text]="employee.name">Name</p>
<p [text]="employee.age">Age</p>
<p [text]="employee.vehicle">Vehicle</p>
<!-- Pressing this button changes state to: -->
<button
  on="tap:AMP.setState({
              employee: {
                name: 'John Smith',
                age: 47,
                vehicle: 'Car'
              }
            })"
>
  Set employee to John Smith
</button>
<!-- Pressing this button recursively merges the object literal argument,  -->
<!-- `{employee: {age: 64}}`, into the existing state. -->

<button
  on="tap:AMP.setState({
              employee: {
                age: 64
              }
            })"
>
  Set employee age to 64
</button>
<!-- The value updates from 47 to 64 at employee.age.  -->
<!-- No other values change. -->

<p [text]="myExpressionsState.foo"></p>
<!-- 1 + '1'; // 11 -->
<button on="tap:AMP.setState({myExpressionsState: {foo: 1 + '1'}})">
  foo: 1 + "1"
</button>
<!-- 1 + +'1'; // 2 -->
<button on="tap:AMP.setState({myExpressionsState: {foo: 1 + + '1'}})">
  foo: 1 + + "1"
</button>
<!-- !0; // true -->
<button on="tap:AMP.setState({myExpressionsState: {foo: !0}})">foo: !0</button>
<!-- null || 'default'; // 'default' -->
<button on="tap:AMP.setState({myExpressionsState: {foo: null || 'default'}})">
  null || "default"
</button>
<!-- [1, 2, 3].map(x => x + 1); // 2,3,4 -->
<button
  on="tap:AMP.setState({myExpressionsState: {foo: [1, 2, 3].map(x => x + 1)}})"
>
  [1, 2, 3].map(x => x + 1)
</button>

<amp-state id="myArrayState">
  <script type="application/json">
    {
      "foo": [1, 2, 3],
      "bar": ["hello", "world", "bar", "baz"],
      "baz": "Hello world, welcome to amp-bind"
    }
  </script>
</amp-state>
<p [text]="'concat: ' + myArrayState.foo.concat(4)">concat: 1, 2, 3</p>
<p [text]="'filter: ' + myArrayState.bar.filter(word => word.length > 3)">
  filter: words with less than three letter
</p>
<p [text]="'includes: ' + myArrayState.bar.includes('hello' || 'world')">
  includes: "hello" or "world"
</p>
<p [text]="'indexOf: ' + myArrayState.bar.indexOf('world')">indexOf: "world"</p>
<p [text]="'join: ' + myArrayState.bar.join('-')">
  join: all words with a dash
</p>
<p [text]="'lastIndexOf: ' + myArrayState.baz.lastIndexOf('amp-bind')">
  lastIndexOf: "amp-bind"
</p>
<p [text]="'map: ' + myArrayState.foo.map((x, i) => x + i)">
  map: add each number to previous number
</p>
<p [text]="'reduce: ' + myArrayState.foo.reduce((x, i) => x + i)">
  reduce: add all numbers in array together
</p>
<p [text]="'slice: ' + myArrayState.bar.slice(1,3)">
  slice: return words at index 1 and 3
</p>
<p [text]="'some: ' + myArrayState.foo.some(x => x < 2)">
  some: some numbers are less than 2
</p>
<p [text]="'sort: ' + myArrayState.bar.sort()">
  sort: place words in alphabetical order
</p>
<p [text]="'splice: ' + myArrayState.bar.splice(2, 0, 'amp-bind')">
  splice: place "amp-bind" at index 2
</p>
<button on="tap:AMP.setState({})">Evaluate</button>

<p [text]="'toExponential: ' + (100).toExponential(5)">
  toExponential: 100 to the exponent of 5
</p>
<p [text]="'toFixed: ' + (1.99).toFixed(1)">
  toFixed: 1.99 rounded and fixed to first decimal
</p>
<p [text]="'toPrecision: ' + (1.234567).toPrecision(3)">
  toPrecision: 1.234567 returned as a string to the third digit
</p>
<p [text]="'toString ' + (3.14).toString()">
  toString: 3.14 returned as a string
</p>
<button on="tap:AMP.setState({})">Evaluate</button>

<amp-state id="myStringState">
  <script type="application/json">
    {
      "foo": "Hello world",
      "bar": ", welcome to amp-bind"
    }
  </script>
</amp-state>
<p [text]="'charAt: ' + myStringState.foo.charAt(6)">
  charAt: The character at index 6
</p>
<p [text]="'charCodeAt: ' + myStringState.foo.charCodeAt(6)">
  charCodeAt: The UTF-16 code unit of the character at index 6
</p>
<p [text]="'concat: ' + myStringState.foo.concat(myState.bar)">
  concat: Combine foo and bar
</p>
<p [text]="'lastIndexOf: ' + myStringState.foo.lastIndexOf('w')">
  lastIndexOf: The index of "w"
</p>
<p [text]="'replace: ' + myStringState.foo.replace('world', 'amp-bind')">
  replace: Replace "world" with "amp-bind"
</p>
<p [text]="'slice: ' + myStringState.foo.slice(5)">
  slice: Extract the first 5 characters
</p>
<p [text]="'split: ' + myStringState.foo.split(' ')">
  split: Split words at space and return as array
</p>
<p [text]="'toLowerCase: ' + myStringState.foo.toLowerCase()">
  toLowerCase: Make all letters lower case
</p>
<p [text]="'toUpperCase: ' + myStringState.foo.toUpperCase()">
  toUpperCase: Make all letters upper case
</p>
<button on="tap:AMP.setState({})">Evaluate</button>

<p [text]="'abs: ' + abs(5 - 9)">abs: absolute number of 5 - 9</p>
<p [text]="'ceil: ' + ceil(1.01)">
  abs: round 1.01 up to the next largest whole number
</p>
<p [text]="'floor: ' + floor(1.99)">floor: round 1.99 down to a whole number</p>
<p [text]="'max: ' + max(100, 4, 98)">max: return largest number</p>
<p [text]="'min: ' + min(100, 4, 98)">min: return smalled number</p>
<p [text]="'pow: ' + pow(5, 3)">pow: return 5 to the power of 3</p>
<p [text]="'random: ' + random()">
  random: return a number greater than 0 and less than 1
</p>
<p [text]="'round: ' + round(1.51)">round: round 1.51</p>
<p [text]="'sign: ' + sign(-9)">sign: evaluate if positive or negative</p>
<button on="tap:AMP.setState({})">Evaluate</button>

<amp-state id="myObjectState">
  <script type="application/json">
    {
      "hello": "world",
      "foo": "bar"
    }
  </script>
</amp-state>
<p [text]="'keys: ' + keys(myObjectState)">
  keys: myObjectState JSON object keys
</p>
<p [text]="'values: ' + values(myObjectState)">
  values: myObjectState JSON object values
</p>
<button on="tap:AMP.setState({})">Evaluate</button>

<p [text]="'encodeURI: ' + encodeURI('https://amp.org.cn/😉')">
  encodeURI: Encode a URI and ignore protocol prefix
</p>
<p [text]="'encodeURIComponent: ' + encodeURIComponent('https://amp.org.cn/😉')">
  encodeURIComponent: Encode a URI
</p>
<button on="tap:AMP.setState({})">Evaluate</button>

<amp-bind-macro
  id="circleArea"
  arguments="radius"
  expression="3.14 * radius * radius"
></amp-bind-macro>
<p>
  Input a radius value
</p>
<input
  type="number"
  min="0"
  max="100"
  value="0"
  on="input-throttled:AMP.setState({myCircle:{radius: event.value}})"
/>
<p>
  The circle has an area of
  <span [text]="circleArea(myCircle.radius)">0</span>.
</p>

<amp-video
  [controls]="controls"
  width="640"
  height="360"
  layout="responsive"
  poster="/static/inline-examples/images/kitten-playing.png"
>
  <source
    src="/static/inline-examples/videos/kitten-playing.webm"
    type="video/webm"
  />
  <source
    src="/static/inline-examples/videos/kitten-playing.mp4"
    type="video/mp4"
  />
  <div fallback>
    <p>This browser does not support the video element.</p>
  </div>
</amp-video>
<button on="tap:AMP.setState({ controls: true })">
  Controls
</button>
<button on="tap:AMP.setState({ controls: false })">
  No Controls
</button>

<p [hidden]="hiddenState">Hello there!</p>
<button on="tap:AMP.setState({hiddenState: true})">Hide</button>
<button on="tap:AMP.setState({hiddenState: false})">Show</button>

<amp-img
  src="https://unsplash.it/400/200"
  width="200"
  [width]="myImageDimension.width"
  height="100"
  [height]="myImageDimension.height"
>
</amp-img>
<button
  on="tap:AMP.setState({
              myImageDimension: {
              width: 400,
              height: 200
              }
              })"
>
  Change size
</button>