We tried to set expectations early on that this tutorial is more focused towards doing rather than explaining. Now that the doing is done, let's fill in gaps on concepts that we applied.
We used React components and APIs here with little explanation. Having a solid understanding of React is essential to using Expo to build your app. We recommend reading the Main Concepts section
and the Hooks section
of the React documentation.
- You understand how to use
React.useState, that it is a hook, and what the equivalent for React class components is.
- Add a new button to clear the selected image state.
- You can create a reusable
Button component to clean up duplication of
- You can move part of the code from our app into a separate file, export it, and import it successfully into App.js.
- Remove all of the styles from your app and attempt to re-create them from scratch, only referring to the View and Text API reference pages when needed.
This is the way you position and size the components on your screen. Learn more about it in Height & Width
and Layout with Flexbox
in the React Native documentation.
- Remove the logo image and re-build it using just
Text. Use the "sunrise over mountains" 🌄 emoji where needed.
- You will typically be referred back to
app.json as part of guides that explain how to accomplish specific tasks, as such there isn't much you need to learn beyond its existence and how to use specific properties as the need arises.
Topics that we didn't cover and you will soon care about
Most apps have multiple screens, we just have one here! Learn more about how to add navigation to your app by following the Fundamentals guide
in the React Navigation documentation.
Sometimes things go wrong, and when they do you need to use debugging tools to figure out where your code is having trouble. Read more about debugging