freeCodeCamp/curriculum/challenges/english/03-front-end-libraries/react/render-with-an-if-else-cond...

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---
id: 5a24c314108439a4d4036184
title: Render with an If-Else Condition
challengeType: 6
forumTopicId: 301410
dashedName: render-with-an-if-else-condition
---
# --description--
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.
# --instructions--
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.
**Note:** You must write an `if/else` to pass the tests. Use of the ternary operator will not pass here.
# --hints--
`MyComponent` should exist and render.
```js
assert(
(function () {
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
return mockedComponent.find('MyComponent').length === 1;
})()
);
```
When `display` is set to `true`, a `div`, `button`, and `h1` should render.
```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
);
};
```
When `display` is set to `false`, only a `div` and `button` should render.
```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
);
};
```
The render method should use an `if/else` statement to check the condition of `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--
2020-07-13 16:58:50 +00:00
```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>
);
}
}
};
```