Building Your First Web Application: A Todo App

Welcome to your journey of building your first web application! In this blog post, we'll guide you through the process of creating a simple interactive todo app using HTML, CSS, and JavaScript. Whether you're completely new to programming or just getting started with web development, this tutorial will help you grasp the basics while creating a practical project.

Prerequisites

Before we begin, make sure you have a basic understanding of HTML, CSS, and JavaScript. You don't need to be an expert, but a basic grasp of these technologies will be beneficial.

Curriculum Overview

Setting Up the Project:

Create a new folder for your project.
Inside the project folder, create three files: index.html, styles.css, and app.js.

Building the Structure:

Open the index.html file and set up the basic HTML structure.
Link the styles.css file to apply styling to your app.
Create a container with a heading, input field, add button, and an empty unordered list.

Adding Styling:

Open the styles.css file and add styles to make your app visually appealing.
Style the container, input field, button, and task list.

Implementing Functionality:

Open the app.js file and add a DOMContentLoaded event listener.
Select elements using document.getElementById.
Add an event listener to the "Add Task" button to create tasks.

Creating Tasks:

Get the value from the input field and create a new task item.
Append the task item to the task list.

Marking Tasks as Completed:

Add event listeners to task checkboxes to mark tasks as completed.
Style completed tasks with a strikethrough effect.

Deleting Tasks:

Add event listeners to delete buttons to remove tasks.
Use the removeChild method to remove tasks from the list.

Conclusion and Next Steps:

Congratulations! You've built your first interactive web application.
Experiment with further enhancements, such as adding due dates or saving tasks to local storage.

Step-by-Step Walkthrough

Now, let's dive into the step-by-step process of building your todo app.

1. Setting Up the Project

Begin by creating a new folder for your project. Inside this folder, create three files: index.html, styles.css, and app.js.

2. Building the Structure

In your index.html file, set up the basic HTML structure. Link the styles.css file to apply styling to your app. Create a container with a heading, input field, add button, and an empty unordered list.

<!-- index.html -->
<!DOCTYPE html>
<html lang="en">
<head>
  <!-- Add the necessary meta tags and title here -->
  <link rel="stylesheet" href="styles.css">
</head>
<body>
  <div class="container">
    <h1>Todo App</h1>
    <input type="text" id="taskInput" placeholder="Enter a task">
    <button id="addTaskBtn">Add Task</button>
    <ul id="taskList"></ul>
  </div>
  <script src="app.js"></script>
</body>
</html>

3. Adding Styling

In the styles.css file, add styles to make your app visually appealing. Style the container, input field, button, and task list.

/* styles.css */
body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background-color: #f4f4f4;
}

.container {
  /* Add container styling here */
}

/* Add more styling for input, button, and task list */

4. Implementing Functionality

In your app.js file, add a DOMContentLoaded event listener to ensure that your JavaScript code runs after the page is fully loaded.

// app.js
document.addEventListener('DOMContentLoaded', function () {
  // Your code will go here
});

5. Creating Tasks

Inside the event listener, you can start adding functionality. Select elements using document.getElementById and add an event listener to the "Add Task" button.

document.addEventListener('DOMContentLoaded', function () {
  const taskInput = document.getElementById('taskInput');
  const addTaskBtn = document.getElementById('addTaskBtn');
  const taskList = document.getElementById('taskList');

  addTaskBtn.addEventListener('click', function () {
    const taskText = taskInput.value.trim();
    if (taskText !== '') {
      const taskLi = document.createElement('li');
      // Create the task item's structure here
      taskList.appendChild(taskLi);
      taskInput.value = '';
    }
  });
});

6. Marking Tasks as Completed

You can add event listeners to task checkboxes to mark tasks as completed. Also, add styling to completed tasks.

// Inside the DOMContentLoaded event listener
taskList.addEventListener('click', function (event) {
  if (event.target.classList.contains('taskCheckbox')) {
    const taskLi = event.target.parentElement;
    taskLi.classList.toggle('completed');
  }
});

7. Deleting Tasks

Similarly, add event listeners to delete buttons to remove tasks.

// Inside the DOMContentLoaded event listener
taskList.addEventListener('click', function (event) {
  if (event.target.classList.contains('deleteBtn')) {
    const taskLi = event.target.parentElement;
    taskList.removeChild(taskLi);
  }
});

8. Conclusion and Next Steps

Congratulations! You've successfully built your first interactive web application – a todo app. You've learned how to structure an HTML page, style it with CSS, and add interactivity using JavaScript.

As a next step, you can experiment with adding more features to your app, such as due dates, priority levels, or even saving tasks to local storage. This project serves as a great foundation for your journey into web development!

Wrapping Up

Building a todo app is an excellent way to get started with web development. You've learned fundamental concepts like working with the DOM, handling events, and applying CSS styling. This hands-on experience will serve as a strong foundation for your future projects.

Feel free to explore other web development topics, frameworks, and technologies. Remember, practice makes perfect, so keep building and experimenting with new ideas. Happy coding!