Jit-React

Components

What is this? This page teaches one practical part of React. Build interface components from state, props, events, and reusable layouts.

Why use this? Use components when a real page, script, store, report, or workflow needs a result that can be checked instead of guessed.

explainchangepredicttestfix

Small working example

function StatusCard( props )
{
    return <section className="card">
        <h2>{props.title}</h2>
        <p>{props.message}</p>
    </section>;
}

Line-by-line learning

  1. The component is a reusable UI function.
  2. props carries values into the component.
  3. className sets the CSS class in React.
  4. Curly braces insert JavaScript values into JSX.

Change and predict

Change one value in the example, predict the result in plain English, then run or inspect the page to see if you were right.

Rule: a worksheet is not done until the learner can say what changed, why it changed, and how to safely change it back.

Common mistakes

  • Changing several things at once, then not knowing which change caused the result.
  • Copying code without first identifying the one line that proves the idea.
  • Ignoring error messages instead of reading the first useful line.
  • Using a large example before the small example works.

Mini challenge

Make the smallest useful version of Components. It should have one visible result and one safe edit the learner can make.

Real challenge

Use the same idea in a real page, script, checklist, or data flow. Keep it small enough that another beginner can test it in under five minutes.

10 worksheet steps

  1. Worksheet 1: Copy the small React example exactly and identify the output.
  2. Worksheet 2: Circle or write down the one line that creates the main value.
  3. Worksheet 3: Change one word, number, selector, field, or setting and predict what changes.
  4. Worksheet 4: Run the example again and compare the real result to your prediction.
  5. Worksheet 5: Break one line on purpose, read the first error, then fix it.
  6. Worksheet 6: Add one extra item or rule using the same pattern.
  7. Worksheet 7: Remove one item or rule and explain what disappeared.
  8. Worksheet 8: Rename one value clearly so the code or checklist explains itself.
  9. Worksheet 9: Create a second tiny example from memory without looking.
  10. Worksheet 10: Explain Components to another beginner using only plain language.

Self-check

  1. Can I explain what Components means without jargon?
  2. Can I point to the exact line or item that creates the visible result?
  3. Can I make one safe change and predict the result before checking?
  4. Can I fix one intentional mistake?
  5. Can I reuse the pattern on a new small example?

Quiz

  1. What is the safest first step?
  2. Why should you change only one thing at a time?
  3. What should you do before adding more?
  4. Why should you record what changed?
  5. What error should you fix first?

Try This

Build one small version of this idea. Keep it simple, test it, then explain what changed.