* chore: rename APIs and Microservices to include "Backend" (#42515) * fix typo * fix typo * undo change * Corrected grammar mistake Corrected a grammar mistake by removing a comma. * change APIs and Microservices cert title * update title * Change APIs and Microservices certi title * Update translations.json * update title * feat(curriculum): rename apis and microservices cert * rename folder structure * rename certificate * rename learn Markdown * apis-and-microservices -> back-end-development-and-apis * update backend meta * update i18n langs and cypress test Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * fix: add development to front-end libraries (#42512) * fix: added-the-word-Development-to-front-end-libraries * fix/added-the-word-Development-to-front-end-libraries * fix/added-word-development-to-front-end-libraries-in-other-related-files * fix/added-the-word-Development-to-front-end-and-all-related-files * fix/removed-typos-from-last-commit-in-index.md * fix/reverted-changes-that-i-made-to-dependecies * fix/removed xvfg * fix/reverted changes that i made to package.json * remove unwanted changes * front-end-development-libraries changes * rename backend certSlug and README * update i18n folder names and keys * test: add legacy path redirect tests This uses serve.json from the client-config repo, since we currently use that in production * fix: create public dir before moving serve.json * fix: add missing script * refactor: collect redirect tests * test: convert to cy.location for stricter tests * rename certificate folder to 00-certificates * change crowdin config to recognise new certificates location * allow translations to be used Co-authored-by: Nicholas Carrigan (he/him) <nhcarrigan@gmail.com> * add forwards slashes to path redirects * fix cypress path tests again * plese cypress * fix: test different challenge Okay so I literally have no idea why this one particular challenge fails in Cypress Firefox ONLY. Tom and I paired and spun a full build instance and confirmed in Firefox the page loads and redirects as expected. Changing to another bootstrap challenge passes Cypress firefox locally. Absolutely boggled by this. AAAAAAAAAAAAAAA * fix: separate the test Okay apparently the test does not work unless we separate it into a different `it` statement. >:( >:( >:( >:( Co-authored-by: Sujal Gupta <55016909+heysujal@users.noreply.github.com> Co-authored-by: Noor Fakhry <65724923+NoorFakhry@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Nicholas Carrigan (he/him) <nhcarrigan@gmail.com>
156 lines
4.0 KiB
Markdown
156 lines
4.0 KiB
Markdown
---
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id: 5a24c314108439a4d4036184
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title: Render with an If-Else Condition
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challengeType: 6
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forumTopicId: 301410
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dashedName: render-with-an-if-else-condition
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---
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# --description--
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Another application of using JavaScript to control your rendered view is to tie the elements that are rendered to a condition. When the condition is true, one view renders. When it's false, it's a different view. You can do this with a standard `if/else` statement in the `render()` method of a React component.
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# --instructions--
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MyComponent contains a `boolean` in its state which tracks whether you want to display some element in the UI or not. The `button` toggles the state of this value. Currently, it renders the same UI every time. Rewrite the `render()` method with an `if/else` statement so that if `display` is `true`, you return the current markup. Otherwise, return the markup without the `h1` element.
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**Note:** You must write an `if/else` to pass the tests. Use of the ternary operator will not pass here.
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# --hints--
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`MyComponent` should exist and render.
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```js
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assert(
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(function () {
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const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
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return mockedComponent.find('MyComponent').length === 1;
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})()
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);
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```
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When `display` is set to `true`, a `div`, `button`, and `h1` should render.
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```js
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async () => {
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const waitForIt = (fn) =>
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new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250));
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const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
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const state_1 = () => {
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mockedComponent.setState({ display: true });
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return waitForIt(() => mockedComponent);
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};
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const updated = await state_1();
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assert(
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mockedComponent.find('div').length === 1 &&
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mockedComponent.find('div').children().length === 2 &&
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mockedComponent.find('button').length === 1 &&
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mockedComponent.find('h1').length === 1
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);
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};
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```
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When `display` is set to `false`, only a `div` and `button` should render.
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```js
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async () => {
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const waitForIt = (fn) =>
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new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250));
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const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
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const state_1 = () => {
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mockedComponent.setState({ display: false });
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return waitForIt(() => mockedComponent);
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};
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const updated = await state_1();
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assert(
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mockedComponent.find('div').length === 1 &&
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mockedComponent.find('div').children().length === 1 &&
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mockedComponent.find('button').length === 1 &&
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mockedComponent.find('h1').length === 0
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);
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};
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```
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The render method should use an `if/else` statement to check the condition of `this.state.display`.
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```js
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(getUserInput) =>
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assert(
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getUserInput('index').includes('if') &&
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getUserInput('index').includes('else')
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);
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```
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# --seed--
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## --after-user-code--
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```jsx
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ReactDOM.render(<MyComponent />, document.getElementById('root'))
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```
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## --seed-contents--
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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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display: true
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}
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this.toggleDisplay = this.toggleDisplay.bind(this);
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}
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toggleDisplay() {
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this.setState((state) => ({
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display: !state.display
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}));
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}
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render() {
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// Change code below this line
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return (
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<div>
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<button onClick={this.toggleDisplay}>Toggle Display</button>
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<h1>Displayed!</h1>
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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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# --solutions--
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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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display: true
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}
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this.toggleDisplay = this.toggleDisplay.bind(this);
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}
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toggleDisplay() {
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this.setState((state) => ({
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display: !state.display
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}));
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}
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render() {
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// Change code below this line
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if (this.state.display) {
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return (
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<div>
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<button onClick={this.toggleDisplay}>Toggle Display</button>
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<h1>Displayed!</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.toggleDisplay}>Toggle Display</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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