DOM Mini Project

This lesson brings together everything you learned in the DOM section. We will build a small, practical feature using real DOM concepts.

The goal is not complexity — it’s clarity and confidence.

Project Overview

We will build a simple interactive feature:

• A button that changes text
• A message that appears and disappears
• Basic user interaction using events

This mirrors how real websites behave.

What You Will Use

• DOM selection
• Event handling
• DOM modification
• Class manipulation

HTML Structure (Concept)

Imagine the following elements exist on the page:

• A button
• A hidden message area

JavaScript will control how these behave.

Step 1: Select Elements

let toggleBtn = document.getElementById("toggleBtn");
let messageBox = document.getElementById("messageBox");
  

We first select the elements we want to control.

Step 2: Add an Event Listener

toggleBtn.addEventListener("click", function () {
  messageBox.innerText = "Welcome to Dataplexa!";
});
  

Clicking the button now updates the message text.

Step 3: Toggle Visibility

Let’s enhance the interaction by toggling visibility.

toggleBtn.addEventListener("click", function () {
  messageBox.classList.toggle("active");
});
  

This creates a clean and responsive interaction.

Real-World Connection

This same pattern is used for:

• Showing success messages
• Opening menus
• Toggling dark mode
• Displaying notifications

You’ve just built a core UI behavior.

Mini Project Challenge

Try extending this project:

• Change button text after click
• Add a timer to auto-hide the message
• Count how many times the button is clicked

These small additions build real confidence.

Common Mistakes

• Forgetting to select elements correctly
• Overwriting text unintentionally
• Adding too many event listeners

Keep logic simple and readable.

What You Achieved

By completing this mini project, you:

• Used DOM selection correctly
• Handled user events
• Modified page content dynamically
• Built a real interactive feature

What Comes Next?

You have completed the DOM & Browser section.

In the next lesson, we move into modern JavaScript and ES6 concepts.