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'll need to install react-router-dom. There is another package simply called react-router but this package isn't intended for web apps that run in the browser.

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 />? <BrowserRouter />s lets us link different urls to different states (and therefor UIs) in a SPA.
4. Why would we use <BrowserRouter /> in our apps? It helps with seperation of concerns/SRP, and also helps the user navigate the site with a browser. For example: sharing a link to a specific part of an app is impossible with a SPA unless we use something like a <BrowserRouter /> to wrap our app in.

Route Matchers

5. What does the <Route /> component do? The <Route /> component handles conditional rendering based on our current url.
6. How does the <Route /> component check whether it should render something? A <Route /> will have a prop called path that indicates what url path should active for it to render. Using '/' as a path will mean something always renders.
7. What does the <Switch /> component do? A <Switch /> can contain many <Route />s. It's similar to an array or object- it's a container for other components.
8. How does it decide what to render? It will look through it's child <Route />s and if any of those paths are true, they will render. Otherwise it returns null.

Route Changers

9. What does the <Link /> component do? How does a user interact with it? A <Link /> will alter the url on interaction, which in turn will alter the dom if it triggers a <Route />.
10. What does the <NavLink /> component do? How does a user interact with it? A <NavLink /> is similar to a combination of a <Link /> and a <Route />. It sends the user to a certain url, but it's conditionally active when the user is in other places on the site.
11. What does the <Redirect /> component do? A <Redirect /> sends the user to it's prop url automatically when it renders. Eazy Peazy.