In context of Fig. 40(d), add another button namely ‘Revert’ which when pressed, will reverse both the color and index values.

To add a “Revert” button that reverses both the color and index values in the context of “Fig. 40(d)” (presumably an existing web application or image), we can break it down into the following steps:

Step 1: Understand the Current Setup

You likely have a button, some color values, and an index that can be modified. We assume you have an interactive page where the color and index are updated dynamically, either using JavaScript or through CSS manipulations.

Step 2: Create the “Revert” Button

We will create an additional button, “Revert”, that will reverse the changes to both the color and the index when pressed.

Step 3: Implement the Revert Functionality

You need to reverse the changes made to the color and index when the “Revert” button is clicked. This could be done using JavaScript.

Below is an example code snippet that demonstrates how to achieve this:

<!DOCTYPE html>
<html lang=”en”>
<head>
<meta charset=”UTF-8″>
<meta name=”viewport” content=”width=device-width, initial-scale=1.0″>
<title>Revert Button Example</title>
<style>
#colorBox {
width: 200px;
height: 200px;
margin: 20px;
background-color: blue;
display: inline-block;
}

button {
padding: 10px 20px;
font-size: 16px;
cursor: pointer;
}

#index {
margin-top: 20px;
font-size: 18px;
}
</style>
</head>
<body>

<div>
<div id=”colorBox”></div>
<div id=”index”>Index: 0</div>
</div>

<button id=”changeButton”>Change Color and Index</button>
<button id=”revertButton”>Revert</button>

<script>
let colorIndex = 0; // Start with the initial index
const colors = [‘blue’, ‘green’, ‘red’, ‘yellow’]; // Array of colors

// Function to update color and index
function updateColorAndIndex() {
// Change the color based on the colorIndex
const colorBox = document.getElementById(‘colorBox’);
colorBox.style.backgroundColor = colors[colorIndex];

// Update the index display
document.getElementById(‘index’).textContent = ‘Index: ‘ + colorIndex;
}

// Change color and index on button click
document.getElementById(‘changeButton’).addEventListener(‘click’, () => {
colorIndex = (colorIndex + 1) % colors.length; // Cycle through colors
updateColorAndIndex();
});

// Revert color and index on “Revert” button click
document.getElementById(‘revertButton’).addEventListener(‘click’, () => {
// Reverse the index and color by subtracting 1 from the colorIndex
colorIndex = (colorIndex – 1 + colors.length) % colors.length; // Ensure it wraps around properly
updateColorAndIndex();
});

// Initialize the page with the first color and index
updateColorAndIndex();
</script>

</body>
</html>

Explanation:

  1. HTML Structure:

    • We have a div (#colorBox) that changes color when the “Change Color and Index” button is clicked.
    • We have another div (#index) to display the current index.
    • Two buttons are added: one to change the color/index and another one to revert them.

  2. JavaScript Functionality:

    • updateColorAndIndex(): This function updates the background color of the colorBox and the text in the index div based on the current value of colorIndex.
    • Change Button: The “Change Color and Index” button increments the colorIndex, cycling through the colors array.
    • Revert Button: The “Revert” button reverses the color and index by decrementing the colorIndex. We use the modulo operation to ensure the index wraps around properly (when it goes below zero, it loops back to the last color in the array).

  3. CSS:

    • Simple styling is applied to the color box and buttons to make them visible and interactive.

Step 4: Testing the Page

To test, save the code in an .html file and open it in a browser. Press the “Change Color and Index” button to cycle through the colors and the index, and then use the “Revert” button to reverse the action.

Related Questions:

  1. Differentiate between different types of headings in HTML
  2. Elaborate steps and provide code to load a background image in a webpage.
  3. Sketch steps and provide code to apply border and color to a table in a webpage.
  4. Discuss the functionality JavaScript can provide in a webpage with the help of a suitable example code.
  5. Articulate steps and write code to create a scrolling text on a webpage.
  6. List steps to add a video clip in a website which starts playing as the web page loads.
  7. Cite steps on compiling the result of your last examination in a tabular form and display it in a webpage.
  8. Contrast between website and web application.
  9. What is ‘href’ and how is it used
  10. Enlist the optional parameters to open a webpage.
  11. List the frequent tags used in the text of a webpage and their usage.
  12. Explain the role of tag-pair in a document.
  13. How is event-based code used in JavaScript?
  14. Infer about External CSS. Where is it generally used?
  15. What is Document Object Model? Explain with the help of an example.
  16. With the help of sample code, highlight different methods to incorporate CSS code in an HTML webpage.
  17. Create an IPO chart that accepts the ages of four boys and calculates their total and average age. The program should display both the total and the average age.
  18. Create an IPO chart for a scenario where a user enters two numbers. The user selects an operation (addition, subtraction, multiplication, or division), and the output is displayed accordingly.
  19. A child wants to plan a birthday party for their friend. Draw an IPO chart for this situation.
  20. Write down the properties of computational thinking.