We can also make use of fragments along or within other conditional rendering operators such as the AND (&) and OR (||) operator as shown below. Our app should now look and function as demonstrated below:Īdd flex-direction: column to the container CSS rule in the App.css file to have the same output as shown above. Now, we’re making use of the Fragment component in two places, first, as the root element for the returned JSX in the component and secondly as a root element within the ternary operator expression itself where we have the h3, br and button elements as siblings. We can implement the above task with the code below:Ĭonst = useState(false) We’re to render the You’re Logged In text in an h3 tag when the authentication state of the react component is true and render a login button when it’s false. Given that we’re to conditionally render some elements in a react component based on the authentication state of the user. Using React Fragment in Conditional RenderingĬonditional rendering is one of the most fundamental concepts in React, it helps to render different react components based on conditions, prop, and state of the component. Note: We can skip wrapping the element with fragments if we have only one element. The above screenshot shows that there is no redundant tag between the div container element, and a fruit button is the first child of the div container. Then when we check the browser element inspection, we should have the following: When you check your browser, the component should now update as follows:Īs shown above, it’s only the first button that’s now having a yellowgreen background color, while others are having a dark background color. This is where the Fragment component comes to play! We can make use of the Fragment component to resolve this issue by replacing the div JSX element with the component as follows: The above code screenshot shows that the button is not the first child of the container element, and the yellowgreen background color is applied to the div tag which should only serve as a root element but is also now the immediate child of the container element. This is a UI bug due to the redundant div tag we introduced to avoid returning multiple elements in the react component.īelow is what our DOM structure looks like on the Chrome element inspect tool: ❌ The output result above is incorrect because only the first sibling (button) should have the green color and not the background of all four siblings (buttons). Then we target the first button in the buttons sibling within the container element and assign it a yellowgreen background color.īelow will be the output of the above code when you visit your browser: Use the following command to create a new react application:įrom the CSS above code, we center the container class using flexbox then we gave all the buttons with fruit class name a dark background color. Returning multiple JSX from a map function return statement.Returning multiple JSX from a component return statement.Typical use cases of react fragment components include: It allows you to wrap multiple elements without extra DOM elements. We use react fragment components anywhere we need to return multiple elements from JSX from react components (function or class component). The extra node can also be referred to as an extra div, section or span tag, etc. React fragment allows one to add multiple elements to a react component, saving the headache of returning multiple elements for react developers. It is created with the main purpose of resolving the issue where we need to return multiple elements or adjacent JSX multiple elements from a react component without making use of an actual JSX element such as div, section, span, etc that will create an extra node in the DOM. What is a React Fragment?įragment is a react component that was introduced in React v16.2.0 in November 2017. React also suggest we make use of a JSX fragment ( or )or use an empty pair of angle brackets () as the parent wrapper of these multiple JSX elements. The error screen appears when we’re trying to return multiple elements from JSX in a react component. The UI bugs might vary but the syntax errors usually look something like this: However, we may encounter UI bugs or syntax errors if the JSX structures are not properly maintained after breaking large components into junks. React is well-known for thinking in terms of components, which means breaking complex UI components down into smaller ones. Convert Designs to Code with Cop圜at Introduction
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |