How to Determine Profanity in a Sentence in Flutter using Cloud Natural Language API and Vertex AI

Flutter Implementation

Now that we have set up the Cloud Natural Language API and Vertex AI, let’s implement profanity detection in our Flutter app:

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';

class ProfanityDetector {
  final String _apiKey;
  final String _projectId;

  ProfanityDetector(this._apiKey, this._projectId);

  Future<bool> detectProfanity(String sentence) async {
    final url = 'https://language.googleapis.com/v1/documents:analyze?key=$_apiKey';
    final headers = {
      'Content-Type': 'application/json',
    };
    final data = {
      'encodingType': 'UTF8',
      'document': {
        'type': 'PLAIN_TEXT',
        'content': sentence,
      },
    };

    final response = await http.post(Uri.parse(url), headers: headers, body: jsonEncode(data));

    if (response.statusCode == 200) {
      final responseBody = jsonDecode(response.body);
      final annotations = responseBody['responses'][0]['annotations'];

      for (var annotation in annotations) {
        if (annotation['type'] == 'PROFANITY' && annotation['_score'] > 0.5) {
          return true; // Profanity detected
        }
      }

      return false; // No profanity detected
    } else {
      throw Exception('Failed to detect profanity: ${response.statusCode}');
    }
  }
}

In the above code, we create a `ProfanityDetector` class that takes the API key and project ID as parameters. The `detectProfanity` method sends a request to the Cloud Natural Language API with the input sentence and analyzes the response for profanity annotations.

Using the Profanity Detector in Flutter

Now that we have the `ProfanityDetector` class, let’s use it in our Flutter app:

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

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final ProfanityDetector _profanityDetector = ProfanityDetector('YOUR_API_KEY', 'YOUR_PROJECT_ID');
  final TextEditingController _textController = TextEditingController();
  bool _isProfanityDetected = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Profanity Detector'),
      ),
      body: Padding(
        padding: const EdgeInsets.all(20.0),
        child: Column(
          children: [
            TextFormField(
              controller: _textController,
              decoration: InputDecoration(
                labelText: 'Enter a sentence',
                border: OutlineInputBorder(),
              ),
            ),
            SizedBox(height: 20),
            ElevatedButton(
              onPressed: () async {
                final sentence = _textController.text;
                final isProfanityDetected = await _profanityDetector.detectProfanity(sentence);

                setState(() {
                  _isProfanityDetected = isProfanityDetected;
                });
              },
              child: Text('Detect Profanity'),
            ),
            SizedBox(height: 20),
            _isProfanityDetected
                ? Text('Profanity detected!', style: TextStyle(color: Colors.red))
                : Text('No profanity detected.'),
          ],
        ),
      ),
    );
  }
}

In the above code, we create a `MyApp` widget that uses the `ProfanityDetector` class to detect profanity in the input sentence. When the user presses the “Detect Profanity” button, the app sends a request to the Cloud Natural Language API and updates the UI accordingly.

Conclusion

In this article, we explored how to detect profanity in sentences using Flutter, Cloud Natural Language API, and Vertex AI. By following these steps, you can ensure a safe and respectful environment for your users and maintain a positive brand reputation.

Remember to replace `YOUR_API_KEY` and `YOUR_PROJECT_ID` with your actual API key and project ID.

Resources

For more information, check out the following resources:

• Cloud Natural Language API
• Vertex AI
• Flutter

Happy coding!

Frequently Asked Question

Getting ready to navigate the world of profanity detection in Flutter? You’re in the right place! Here are some frequently asked questions to help you get started with the Cloud Natural Language API and Vertex AI.