zachsavn / react_props_state

React: State and Props

Template for React exercises

Getting Started

• Open your command line and navigate to your repos directory (if you do not have a repos folder, then you can use mkdir repos to create one)
• Use this template repository to start a new project in your repos folder: git clone <repo_name> cd repo_name to navigate into your new repo directory
• Make sure to run npm install to fetch the dependencies for the project
• Start Visual Studio Code and select 'Open Folder'. Then select repo_name to open the folder in the editor (or just type code . in your terminal inside the repo directory)
• Follow the instructions on the README.md file to complete exercises
• Open the app.js file to get started

Exercise

• In your App.jsx

1. Create a variable boxes and assign it an empty array
2. Create a variable numBoxes and assign it the number 24
3. Write a loop that iterates from 0 to numBoxes, and pushes a box object to boxes array during each iteration

   {
       id: i,
       color: `rgb(${this.getRandomColor()}, ${this.getRandomColor()}, ${this.getRandomColor()})`
   }
   

4. Assign boxes to the App state
5. Create a method handleBoxClick that takes an HTMLChangeEvent (e) as a param, and does the following:
   • Creates a variable newBoxes
   • Maps through the boxes state
   • If the box id is equal to the event target id value, then set the box's color value to rgb(${this.getRandomColor()}, ${this.getRandomColor()}, ${this.getRandomColor()})
   • Sets the boxes state equal to newBoxes
6. Earlier we used a getRandomColor method. Create this method beneath handleBoxClick. It should:
   • Create a variable rgb that is assigned a random number between 1-255
   • Return rgb
   • This method is called during the creation of the boxes, and during the onclick event listener to randomize the box colors
7. Inside the render method, create a variable renderBoxes that maps through the boxes state, and returns a <Box /> component for each box in the array
8. You should pass the following props to each Box component:
   • key = box.id
   • id = box.id
   • color = box.color
   • handleClick = this.handleBoxClick

• In your Box.jsx

1. Add an onClick attribute to the return div, and pass in the props.handleClick
2. Add an id attribute to the return div, and assign it the props.id
3. Add props.color as the span text content
4. Lastly, add a backgroundColor property to the inline-styling of the return div, and assign it prop.color

• Your finished product should display 24 squares on the DOM, all with random color values. Each square's background color should randomize when you click on it.