flutter_screenguard 1.0.0

A Native screenshot blocking library for Flutter developer, with background customizable after captured. Screenshot detector are also supported.

flutter_screenguard

A Native screenshot blocking plugin for Flutter developer, with background customizable after captured. Screenshot detector are also supported.

https://github.com/user-attachments/assets/ea6cba30-5930-4219-92c5-283db2cf125e

Requirements

• Flutter >=3.7.0
• Dart >=3.4.0 <4.0.0
• iOS >=12.0
• Android compileSDK 34
• Java 17
• Android Gradle Plugin >=8.3.0
• Gradle wrapper >=7.6

Installation

To use this plugin, add flutter_screenguard as a dependency in your pubspec.yaml file

dependencies:
   flutter_screenguard: ^1.0.0

Or you can run this command to install it from the flutter pub.

flutter pub add flutter_screenguard

(Most important!) Post installation for Android

On Android, remember to setup a little bit as you will not receive the background color or the blur effect like in the video example.

Open up [your_project_path]/android/app/src/main/AndroidManifest.xml and add activity com.screenguard.flutter_screenguard.ScreenGuardColorActivity like below

<manifest xmlns:android="http://schemas.android.com/apk/res/android">
    <application ......>
      	<activity
      	  android:name=".MainActivity" .........>
      	  ..........
      	</activity>

+       <activity android:name="com.screenguard.flutter_screenguard.ScreenGuardColorActivity"
+            android:theme="@style/Theme.AppCompat.Translucent"
+            android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|screenSize|smallestScreenSize|uiMode"
+            android:windowSoftInputMode="stateAlwaysVisible|adjustResize"
+            android:exported="false"
+        />
    </application>
</manifest>

Open up [your_project_path]/android/app/src/main/res/values/styles.xml and add style Theme.AppCompat.Translucent like below

<resource>

<style name="AppTheme">your current app style theme.............</style>

+ <style name="Theme.AppCompat.Translucent">
+        <item name="android:windowNoTitle">true</item>
+        <item name="android:windowBackground">@android:color/transparent</item>
+        <item name="android:colorBackgroundCacheHint">@null</item>
+        <item name="android:windowIsTranslucent">true</item>
+        <item name="android:windowAnimationStyle">@null</item>
+        <item name="android:windowSoftInputMode">adjustResize</item>
+ </style>
</resource>

Usage

import the plugin as follow

import 'package:flutter_screenguard/flutter_screenguard.dart';

then, create an instance of FlutterScreenguard as such

import 'package:flutter_screenguard/flutter_screenguard.dart';

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {

  late final FlutterScreenguard _flutterScreenguardPlugin;
  
  @override
  void initState() {
    super.initState();
    _flutterScreenguardPlugin = FlutterScreenguard();
  }
}

register

Activate the screenguard with your custom background color layout.

https://github.com/user-attachments/assets/9ccdc973-a07c-454b-9383-d905f73cdd87

  await _flutterScreenguardPlugin.register(
    color: Colors.red,
  );

  await _flutterScreenguardPlugin.register(
    color: Color(0xFFFFFC31),
    timeAfterResume: const Duration(milliseconds: 2500),
  );

  await _flutterScreenguardPlugin.register(
    color: Color.fromRGBO(178, 178, 178, 1),
    timeAfterResume: const Duration(milliseconds: 3000),
  );

Parameters:

• color: The background color you want to display from, Colors class

• timeAfterResume (Android only): A small amount of time (in milliseconds) for the view to disappear before jumping back to the main application view.

registerWithBlurView

Activate screenguard with a blurred effect view after captured.

Blurview on Android using Blurry.

(Remember to register the instance with a GlobalKey and attach this key to the view before proceed!)

https://github.com/user-attachments/assets/77d40b1f-0e8d-443a-9c85-f57512497fc5

import 'package:flutter_screenguard/flutter_screenguard.dart';

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {

  late final FlutterScreenguard _flutterScreenguardPlugin;

  final GlobalKey globalKey = GlobalKey();
  
  @override
  void initState() {
    super.initState();
    _flutterScreenguardPlugin = FlutterScreenguard(globalKey: globalKey);
  }

  @override
  Widget build(BuildContext context) {
       return RepaintBoundary(
         key: globalKey,
         child: Scaffold(.........)
      );
   }
}

then use as such

await _flutterScreenguardPlugin.registerWithBlurView(
    radius: 6,
    timeAfterResume: const Duration(milliseconds: 2000));

Parameters:

• radius: blur radius value number in between [15, 50], throws warning if smaller than 15 or bigger than 50, exception if smaller than 1.

• timeAfterResume (Android only): A small amount of time (in milliseconds) for the view to disappear before jumping back to the main application view.

Set blur radius smaller than 15 won't help much, as content still look very clear and easy to read. Same with bigger than 50 but content will be shrinked and vanished inside the view, blurring is meaningless. So, between 15 and 50 is enough.

registerWithImage

Activate screenguard with a custom image view and background color.

ImageView using SDWebImage on iOS and Glide on Android for faster loading and caching.

https://github.com/user-attachments/assets/41c63ba2-225a-4654-80a3-c6db2c4cab9b

  await _flutterScreenguardPlugin.registerWithImage(
    uri: 'https://image.shutterstock.com/image-photo/red-mum-flower-photography-on-260nw-2533542589.jpg',
    width: 150,
    height: 300,
    alignment: Alignment.topCenter,
    timeAfterResume: const Duration(milliseconds: 2000),
    color: Colors.green,
  );

Parameters:

• width Width of the image

• height Heigh of the image

• uri Source uri of the image

• color: The background color you want to display from, Colors class

• alignment Position of image predefined in Flutter library based on Alignment constant

• timeAfterResume (Android only): A small amount of time (in milliseconds) for the view to disappear before jumping back to the main application view.

• top Top position of the image

• left Left position of the image

• bottom Bottom of the image

• right Right of the image

`alignment` can't be combined with position(top, left, bottom, right) params cause this will always be checked 1st, and all positions will be skipped if not null.

Set alignment to null if you want to custom your own position with one of position param top, left, bottom or right above.

registerWithoutEffect

(Android only) Activate screenguard without any effect above for Android only.

registerScreenShotEventListener

Activate a screenshot detector and receive an event callback with screenshot information (if allowed) after a screenshot has been triggered successfully.

import 'package:flutter_screenguard/flutter_screenguard_screenshot_event.dart';

then, create an instance of FlutterScreenguardScreenshotEvent as such

import 'package:flutter_screenguard/flutter_screenguard.dart';

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {

  late final FlutterScreenguardScreenshotEvent
      _flutterScreenguardScreenshotListener;
  
  @override
  void initState() {
    super.initState();
    _flutterScreenguardScreenshotListener =
        FlutterScreenguardScreenshotEvent(getScreenshotData: false)
          ..initialize();
  }
}

then use as such

  _flutterScreenguardScreenshotListener.addListener(
    () {
      FileCaptureDetail? data =
          _flutterScreenguardScreenshotListener.value;
      debugPrint(
        'path: ${data?.path}',
      );
      debugPrint(
        'name: ${data?.name}',
      );
      debugPrint(
        'type: ${data?.type}',
      );
    },
  );

If true, callback will return a FileCaptureDetail object containing info of the previous image screenshot.

If false, callback will return null.

registerRecordingEventListener

(iOS only) Activate a screen recording detector and receive an event callback after a record has done.

import 'package:flutter_screenguard/flutter_screenguard_screen_record_event.dart';

then, create an instance of FlutterScreenguardScreenshotEvent as such

import 'package:flutter_screenguard/flutter_screenguard.dart';

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {

  late final FlutterScreenguardScreenRecordingEvent
      _flutterScreenguardScreenRecordingListener;
  
  @override
  void initState() {
    super.initState();
    _flutterScreenguardScreenRecordingEvent =
        FlutterScreenguardScreenRecordingEvent()
          ..initialize();
  }
}

then use as such

  _flutterScreenguardScreenRecordingEvent.addListener(
    () {
      debugPrint(
        'screen is recording!',
      );
    },
  );

unregister

deactivate the screenguard

  await _flutterScreenguardPlugin.unregister();

Testing

iOS Simulator

• If you want to test on iOS simulator, open Simulator, on the top screen, navigate to Device -> Trigger Screenshot. This is applied to iOS 14+.

Android Emulator

• If you want to test on Android Emulator, you can create an emulator with Google Play Service API supported. Then go to Play Store and download any third-party screen record and screenshot app based on your need (XRecorder, AZ, etc....) for testing.

• Android 12+ emulator already provided screenshot and screen record function in Quick Settings Panel.

Limitation

• This library support blocking screenshot for iOS 13+, Android 8+ only.

• Remember to call a function only ONCE and don't combine with other register functions for limitting errors and unexpected problems might happened during testing.

• Please remember that text input will be temporary disabled until calling unregister on Android except registerWithoutEffect. Still working to find a solution.