Logo

Flutter Screenshot Blocker #

A powerful Flutter plugin that prevents screenshots or shows black screen when screenshots are taken. This plugin provides system-level protection using native platform code.

🌟 Features #

✅ System-Level Screenshot Blocking - Uses FLAG_SECURE on Android and secure views on iOS
📱 Black Screen on Screenshot - When screenshots are attempted, they show black screen
📱 Black Screen on Screen recording - Screen recordings will show black screen
🔍 Screenshot Detection - Detect when users attempt to take screenshots
🎯 Widget-Level Protection - Apply protection to specific parts of your app
🔒 Secure App Wrapper - Easy-to-use app-wide protection
📊 Event Streaming - Real-time screenshot attempt notifications
🚀 Cross-Platform - Works on both Android and iOS
💪 Native Implementation - Maximum security with platform-specific code

🚀 Installation #

Add this to your pubspec.yaml:

dependencies:
flutter_screenshot_blocker: ^1.0.2

Run:

flutter pub get

📱 Platform Setup #

🤖 Android Setup #

No additional setup required! The plugin automatically applies FLAG_SECURE to prevent screenshots. You can setup it if needed. So you can use the manifest given below

To block screenshots in your Flutter app, update the AndroidManifest.xml as shown below: (Optional)

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.flutter_screenshot_blocker_example">

    <!-- (Optional) Permission for detecting screenshots -->
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

    <application
        android:label="flutter_screenshot_blocker_example"
        android:name="${applicationName}"
        android:icon="@mipmap/ic_launcher">

        <activity
            android:name=".MainActivity"
            android:exported="true"
            android:launchMode="singleTop"
            android:theme="@style/LaunchTheme"
            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
            android:hardwareAccelerated="true"
            android:windowSoftInputMode="adjustResize">

            <!-- Enable FLAG_SECURE to block screenshots and screen recordings -->
            <meta-data
                android:name="flutter_screenshot_blocker.secure"
                android:value="true" />

            <!-- Flutter theme metadata -->
            <meta-data
                android:name="io.flutter.embedding.android.NormalTheme"
                android:resource="@style/NormalTheme" />

            <intent-filter android:autoVerify="true">
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>

        <meta-data
            android:name="flutterEmbedding"
            android:value="2" />
    </application>
</manifest>

 iOS Setup #

No additional setup required! The plugin uses secure UITextField technique and screenshot detection. You can setup it if needed. So you can use the Info.plist given below

To enable screenshot protection and enhance app security on iOS, add the following keys to your ios/Runner/Info.plist file.

// ios/Runner/Info.plist additions
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <!-- ... existing keys ... -->

  <!-- Add screenshot protection info -->
  <key>NSPhotoLibraryUsageDescription</key>
  <string>This app needs to detect screenshots for security purposes.</string>

  <key>UIRequiredDeviceCapabilities</key>
  <array>
    <string>armv7</string>
  </array>

  <!-- Prevent screenshots in app switcher -->
  <key>UIApplicationSupportsMultipleScenes</key>
  <false/>

  <key>LSRequiresIPhoneOS</key>
  <true/>

  <!-- Security settings -->
  <key>flutter_screenshot_blocker</key>
  <dict>
    <key>enable_protection</key>
    <true/>
    <key>show_security_warning</key>
    <true/>
  </dict>
</dict>
</plist>

📖 Usage #

Method 1: Secure App Wrapper (Easiest) #

Wrap your entire app with SecureApp:

void main() {
  runApp(
    SecureApp(
      enableScreenshotBlocking: true,
      showSecurityWarning: true,
      child: MyApp(),
    ),
  );
}

Method 2: Widget-Level Protection #

Protect specific widgets:

ScreenshotBlockerWidget(
    blockScreenshots: true,
    detectScreenshots: true,
    onScreenshotDetected: (event) {
      print('Screenshot blocked: ${event.type}');
      // Show your custom message
    },
    child: YourSensitiveWidget(),
  );

Method 3: Manual Control #

Control protection manually:

class MyPage extends StatefulWidget {
  @override
  _MyPageState createState() => _MyPageState();
}

class _MyPageState extends State<MyPage> {
  @override
  void initState() {
    super.initState();
    // Enable protection when page loads
    FlutterScreenshotBlocker.enableScreenshotBlocking();
  }

  @override
  void dispose() {
    // Disable protection when leaving page
    FlutterScreenshotBlocker.disableScreenshotBlocking();
    super.dispose();
  }
}

Screenshot Detection Events #

Listen to screenshot attempts:

StreamSubscription? _screenshotSubscription;

@override
void initState() {
  super.initState();

  _screenshotSubscription = FlutterScreenshotBlocker.onScreenshotDetected
      .listen((ScreenshotEvent event) {
        switch (event.type) {
          case 'screenshot_taken':
            showDialog(
              context: context,
              builder: (_) => AlertDialog(
                title: Text('Screenshot Detected!'),
                content: Text('Screenshots are not allowed in this app.'),
                actions: [
                  TextButton(
                    onPressed: () => Navigator.pop(context),
                    child: Text('OK'),
                  ),
                ],
              ),
            );
            break;
          case 'screenshot_blocked':
            ScaffoldMessenger.of(context).showSnackBar(
              SnackBar(
                content: Text('Screenshot blocked for security!'),
                backgroundColor: Colors.red,
              ),
            );
            break;
        }
      });
}

@override
void dispose() {
  _screenshotSubscription?.cancel();
  super.dispose();
}

⚙️ API Reference #