cdaz5 / react-initial-state-lab-web-051517

React Initial State Lab

Overview

In this lab, you'll set initial state in a React component and distinguish between state and props.

Image slider

Let's pretend we're making an awesome slider for our new portfolio site. Naturally, we'll use React to do so! We have to start somewhere, so in this lab we'll just focus on setting up the initial state of the slider.

1. In the components/ImageSlider.js file, create an ImageSlider React component.
2. Its initial state should have a property called currentSlideIndex that starts at 0.
3. It should only render out the text 'I am on slide <CURRENT_SLIDE>', where <CURRENT_SLIDE> is the value of this.state.currentSlideIndex.

A bomb timer

Take a moment to think about what a bomb does and how it works. Don't get all into the nitty gritty — what we're going to focus on right now is the timer. Let's create a component that represents a bomb timer that counts down until it reaches 0. However, the only thing we're going to focus on right now is setting the initial state of the bomb: the amount of seconds left on the timer. Since bomb timers can differ, we'll pass in a prop to our Bomb component to determine what the starting count should be.

1. In the components/Bomb.js file, create a Bomb React component.
2. Its initial state should have a property called secondsLeft.
3. The initial value of secondsLeft is set by passing in an initialCount prop to the Bomb component. Don't forget to pass the argument props into the constructor (i.e., constructor(props)).
4. It should render the text '<SECONDS_LEFT> seconds left before I go boom!', where <SECONDS_LEFT> is the value of secondsLeft.
5. If secondsLeft equals 0, it should render 'Boom!' instead.

Resources

• Thinking in React