React Router Prework.md

React Router Prework

This gist contains a short assignment I'd like everyone to complete before our formal lesson. The prework involves reading some of the React Router documentation, and will allow us to keep the lesson more hands on.

Instructions

1. Fork this gist
2. On your own copy, go through the listed readings and answer associated questions
3. Comment a link to your forked copy on the original gist

Questions / Readings

Router Overview

React Router is a library that allows us to make our single page React applications mimic the behavior of multipage apps. It provides the ability to use browser history, allowing users to navigate with forward / back buttons and bookmark links to specific views of the app. Most modern sites use some form of routing. React Router exposes this functionality through a series of components. Let's start by looking at the overall structure of an app using router:

1. Take a look at the quick start page of the React Router docs. Take note of the syntax and organization of the page. No worries if this looks unclear right now! (nothing to answer here)

2. What package do we need to install to use React Router?

We need to install the react router dom, using npm install react-router-dom.

Router Components

React Router provides a series of helpful components that allow our apps to use routing. These can be split into roughly 3 categories:

• Routers
• Route Matcher
• Route Changers

Routers

Any code that uses a React-Router-provided component must be wrapped in a router component. There are lots of router components we can use, but we'll focus on one in particular. Let's look into the docs to learn more.

3. What is a <BrowserRouter />? It is a package/componet that uses the HTML5 history API (pushState, replaceState and the popstate event) to keep your UI in sync with the URL.

4. Why would we use <BrowserRouter /> in our apps? React Router is a package that allows you to configure routes that show only the components you specify on the page depending on the route. For example, if you have a long list of movies and only want to show the user's favorites when they click on a 'favorites' button, you can do that with React Router.

To use a router, just make sure it is rendered at the root of your element hierarchy. Typically you’ll wrap your top-level <App> element in a router <BrowserRouter /> component.

Route Matchers

5. What does the <Route /> component do? The Route component most basic responsibility is to render some UI when its path matches the current URL.

6. How does the <Route /> component check whether it should render something? By checking the when the <Route>'s path matches the current URL, it renders its children (your component). It checks the <Route path='/' />

7. What does the <Switch /> component do? When a <Switch> is rendered, it searches through its children <Route> elements to find one whose path matches the current URL. When it finds one, it renders that <Route> and ignores all others

8. How does it decide what to render? It renders the first child <Route> or <Redirect> that matches the location/path, bascially works as a conditional.

Route Changers

9. What does the <Link /> component do? How does a user interact with it? React Router provides a <Link> component to create links in your application. Wherever you render a <Link>, an anchor (<a>) will be rendered in your HTML document.

10. What does the <NavLink /> component do? How does a user interact with it? The <NavLink> is a special type of <Link> that can style itself as “active” when its to prop matches the current location. It will add styling attributes to the rendered element when it matches the current URL.

11. What does the <Redirect /> component do? Any time that you want to force navigation, you can render a <Redirect>. When a <Redirect> renders, it will navigate using its to= prop.