Files
Shaun Hamilton c2a11ad00d feat: add 'back/front end' in curriculum (#42596)
* 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>
2021-08-13 21:57:13 -05:00

156 lines
4.2 KiB
Markdown

---
id: 5a24c314108439a4d4036184
title: Renderizar com uma condição if-else
challengeType: 6
forumTopicId: 301410
dashedName: render-with-an-if-else-condition
---
# --description--
Outra aplicação de usar JavaScript para controlar sua visão renderizada é associar os elementos que são renderizados em uma condição. Quando a condição é verdadeira, uma visão renderiza. Quando é falso, é uma visão diferente. Você pode fazer isso com uma instrução padrão `if/else` no método `render()` de um componente React.
# --instructions--
MyComponent contém um `boolean` em seu estado que rastreia se você deseja exibir algum elemento na interface do usuário ou não. O `button` alterna o estado deste valor. No momento, ele renderiza a mesma interface do usuário todas as vezes. Reescreva o método `render()` com uma instrução `if/else` para que se `display` for `true`, você retorna a marcação atual. Caso contrário, retorne a marcação sem o elemento `h1`.
**Observação:** você deve escrever um `if/else` para passar nos testes. O uso do operador ternário não passará aqui.
# --hints--
`MyComponent` deve existir e renderizar.
```js
assert(
(function () {
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
return mockedComponent.find('MyComponent').length === 1;
})()
);
```
Quando `display` é definido como `true`, uma `div`, um `button`, e um `h1` devem renderizar.
```js
async () => {
const waitForIt = (fn) =>
new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250));
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
const state_1 = () => {
mockedComponent.setState({ display: true });
return waitForIt(() => mockedComponent);
};
const updated = await state_1();
assert(
mockedComponent.find('div').length === 1 &&
mockedComponent.find('div').children().length === 2 &&
mockedComponent.find('button').length === 1 &&
mockedComponent.find('h1').length === 1
);
};
```
Quando `display` é definido como `false`, apenas uma `div` e um `button` devem renderizar.
```js
async () => {
const waitForIt = (fn) =>
new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250));
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
const state_1 = () => {
mockedComponent.setState({ display: false });
return waitForIt(() => mockedComponent);
};
const updated = await state_1();
assert(
mockedComponent.find('div').length === 1 &&
mockedComponent.find('div').children().length === 1 &&
mockedComponent.find('button').length === 1 &&
mockedComponent.find('h1').length === 0
);
};
```
O método de renderização deve usar um comando `if/else` para verificar a condição de `this.state.display`.
```js
(getUserInput) =>
assert(
getUserInput('index').includes('if') &&
getUserInput('index').includes('else')
);
```
# --seed--
## --after-user-code--
```jsx
ReactDOM.render(<MyComponent />, document.getElementById('root'))
```
## --seed-contents--
```jsx
class MyComponent extends React.Component {
constructor(props) {
super(props);
this.state = {
display: true
}
this.toggleDisplay = this.toggleDisplay.bind(this);
}
toggleDisplay() {
this.setState((state) => ({
display: !state.display
}));
}
render() {
// Change code below this line
return (
<div>
<button onClick={this.toggleDisplay}>Toggle Display</button>
<h1>Displayed!</h1>
</div>
);
}
};
```
# --solutions--
```jsx
class MyComponent extends React.Component {
constructor(props) {
super(props);
this.state = {
display: true
}
this.toggleDisplay = this.toggleDisplay.bind(this);
}
toggleDisplay() {
this.setState((state) => ({
display: !state.display
}));
}
render() {
// Change code below this line
if (this.state.display) {
return (
<div>
<button onClick={this.toggleDisplay}>Toggle Display</button>
<h1>Displayed!</h1>
</div>
);
} else {
return (
<div>
<button onClick={this.toggleDisplay}>Toggle Display</button>
</div>
);
}
}
};
```