flutter_epub_viewer: How to change text color of “Table of Contents”?

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Summary

The flutter_epub_viewer package is used to display EPUB files in Flutter applications. However, the default text color of the “Table of Contents” anchor text is blue, which may not be desirable for all applications. This article explores the root cause of this issue and provides a solution to customize the text color.

Root Cause

The root cause of this issue is that the flutter_epub_viewer package uses a default CSS style for the EPUB content, which includes the blue text color for anchor text. The package does not provide a direct way to override this style.

Why This Happens in Real Systems

This issue occurs in real systems because:

  • The flutter_epub_viewer package is designed to provide a basic EPUB viewer functionality
  • The package uses a default CSS style to render the EPUB content
  • The default CSS style includes the blue text color for anchor text
  • The package does not provide a direct way to customize the CSS style

Real-World Impact

The real-world impact of this issue is:

  • The default blue text color may not match the application’s theme or design
  • The application may not be accessible for users with certain visual impairments
  • The application may not provide a consistent user experience

Example or Code

import 'package:flutter/material.dart';
import 'package:flutter_epub_viewer/flutter_epub_viewer.dart';

class CustomEpubViewer extends StatefulWidget {
  @override
  _CustomEpubViewerState createState() => _CustomEpubViewerState();
}

class _CustomEpubViewerState extends State {
  @override
  Widget build(BuildContext context) {
    return EpubViewer(
      // Use a custom CSS style to override the default text color
      cssTheme: '''
        a {
          color: #ff0000; // Red color
        }
      ''',
      // ...
    );
  }
}

How Senior Engineers Fix It

Senior engineers fix this issue by:

  • Customizing the CSS style used by the flutter_epub_viewer package
  • Overriding the default text color with a custom color
  • Using a consistent theme throughout the application
  • Testing the application for accessibility and user experience

Why Juniors Miss It

Juniors may miss this issue because:

  • They may not be familiar with the flutter_epub_viewer package and its limitations
  • They may not understand the importance of customizing the CSS style for accessibility and user experience
  • They may not know how to override the default text color using a custom CSS style
  • They may not test the application thoroughly for accessibility and user experience