ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
136 lines
2.8 KiB
Markdown
136 lines
2.8 KiB
Markdown
---
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id: 587d7fa8367417b2b2512bc9
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title: Update the Height of an Element Dynamically
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challengeType: 6
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forumTopicId: 301493
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dashedName: update-the-height-of-an-element-dynamically
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---
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# --description--
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The previous challenges covered how to display data from an array and how to add CSS classes. You can combine these lessons to create a simple bar chart. There are two steps to this:
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1) Create a `div` for each data point in the array
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2) Give each `div` a dynamic height, using a callback function in the `style()` method that sets height equal to the data value
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Recall the format to set a style using a callback function:
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`selection.style("cssProperty", (d) => d)`
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# --instructions--
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Add the `style()` method to the code in the editor to set the `height` property for each element. Use a callback function to return the value of the data point with the string "px" added to it.
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# --hints--
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The first `div` should have a `height` of 12 pixels.
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```js
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assert($('div').eq(0)[0].style.height === '12px');
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```
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The second `div` should have a `height` of 31 pixels.
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```js
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assert($('div').eq(1)[0].style.height === '31px');
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```
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The third `div` should have a `height` of 22 pixels.
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```js
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assert($('div').eq(2)[0].style.height === '22px');
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```
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The fourth `div` should have a `height` of 17 pixels.
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```js
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assert($('div').eq(3)[0].style.height === '17px');
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```
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The fifth `div` should have a `height` of 25 pixels.
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```js
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assert($('div').eq(4)[0].style.height === '25px');
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```
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The sixth `div` should have a `height` of 18 pixels.
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```js
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assert($('div').eq(5)[0].style.height === '18px');
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```
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The seventh `div` should have a `height` of 29 pixels.
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```js
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assert($('div').eq(6)[0].style.height === '29px');
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```
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The eighth `div` should have a `height` of 14 pixels.
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```js
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assert($('div').eq(7)[0].style.height === '14px');
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```
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The ninth `div` should have a `height` of 9 pixels.
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```js
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assert($('div').eq(8)[0].style.height === '9px');
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```
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# --seed--
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## --seed-contents--
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```html
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<style>
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.bar {
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width: 25px;
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height: 100px;
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display: inline-block;
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background-color: blue;
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}
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</style>
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<body>
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<script>
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const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
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d3.select("body").selectAll("div")
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.data(dataset)
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.enter()
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.append("div")
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.attr("class", "bar")
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// Add your code below this line
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// Add your code above this line
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</script>
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</body>
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```
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# --solutions--
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```html
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<style>
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.bar {
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width: 25px;
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height: 100px;
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display: inline-block;
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background-color: blue;
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}
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</style>
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<body>
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<script>
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const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];
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d3.select("body").selectAll("div")
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.data(dataset)
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.enter()
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.append("div")
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.attr("class", "bar")
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.style('height', d => `${d}px`)
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</script>
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</body>
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```
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