92 lines
3.1 KiB
Markdown
92 lines
3.1 KiB
Markdown
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---
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id: 5a24c314108439a4d4036176
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title: Use State to Toggle an Element
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challengeType: 6
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isRequired: false
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videoUrl: ''
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localeTitle: ''
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---
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## Description
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<section id="description"> يمكنك استخدام <code>state</code> في تطبيقات React بطرق أكثر تعقيدًا من تلك التي شاهدتها حتى الآن. أحد الأمثلة على ذلك هو مراقبة حالة القيمة ، ثم عرض واجهة المستخدم بشكل مشروط بناءً على هذه القيمة. هناك عدة طرق مختلفة لإنجاز هذا ، ويظهر محرر الشفرة طريقة واحدة. </section>
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## Instructions
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undefined
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: ''
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testString: 'assert.strictEqual(Enzyme.mount(React.createElement(MyComponent)).find("div").find("button").length, 1, "<code>MyComponent</code> should return a <code>div</code> element which contains a <code>button</code>.");'
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- text: يجب تهيئة حالة <code>MyComponent</code> مع تعيين خاصية <code>visibility</code> إلى <code>false</code> .
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testString: 'assert.strictEqual(Enzyme.mount(React.createElement(MyComponent)).state("visibility"), false, "The state of <code>MyComponent</code> should initialize with a <code>visibility</code> property set to <code>false</code>.");'
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- text: ''
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testString: 'async () => { const waitForIt = (fn) => new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250)); const mockedComponent = Enzyme.mount(React.createElement(MyComponent)); const first = () => { mockedComponent.setState({ visibility: false }); return waitForIt(() => mockedComponent.state("visibility")); }; const second = () => { mockedComponent.find("button").simulate("click"); return waitForIt(() => mockedComponent.state("visibility")); }; const third = () => { mockedComponent.find("button").simulate("click"); return waitForIt(() => mockedComponent.state("visibility")); }; const firstValue = await first(); const secondValue = await second(); const thirdValue = await third(); assert(!firstValue && secondValue && !thirdValue, "Clicking the button element should toggle the <code>visibility</code> property in state between <code>true</code> and <code>false</code>."); }; '
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='jsx-seed'>
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```jsx
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class MyComponent extends React.Component {
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constructor(props) {
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super(props);
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this.state = {
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visibility: false
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};
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// change code below this line
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// change code above this line
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}
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// change code below this line
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// change code above this line
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render() {
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if (this.state.visibility) {
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return (
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<div>
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<button onClick={this.toggleVisibility}>Click Me</button>
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<h1>Now you see me!</h1>
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</div>
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);
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} else {
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return (
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<div>
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<button onClick={this.toggleVisibility}>Click Me</button>
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</div>
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);
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}
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}
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};
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```
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</div>
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### After Test
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<div id='jsx-teardown'>
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```js
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console.info('after the test');
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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