在颤动中将指纹读取为字符串

Question

我有一个在 android 上运行的应用程序，它使用指纹进行身份验证。该应用程序正在运行，它正在返回我想要的。但我仍然想读取指纹散列或字符串，以便我可以为另一个项目散列它。到目前为止我的代码：

main.dart

import 'package:fingerprint/secondpage.dart';
  import 'package:flutter/cupertino.dart';
  import 'package:flutter/material.dart';
  import 'package:flutter/services.dart';
  import 'package:local_auth/local_auth.dart';

  void main() {
    runApp(MaterialApp(
         debugShowCheckedModeBanner: false,
         home: FingerprintApp(),
         ));
   }

 class FingerprintApp extends StatefulWidget{


 @override
 _FingerprintAppState createState() => _FingerprintAppState();


}


class _FingerprintAppState extends State<FingerprintApp>{

LocalAuthentication auth = LocalAuthentication();

bool _canCheckBiometric ;

List<BiometricType> _availableBiometrics;
String autherized = "Not autherized";

Future<void> _checkBiometric() async {
  bool canCheckBiometric;
  try {
     canCheckBiometric = await auth.canCheckBiometrics;
  } on PlatformException catch (e) {
  print(e);
 }
if (!mounted) return;
setState(() {
  _canCheckBiometric = canCheckBiometric;
});
}

Future<void> _getAvailableBiometric() async {
  List<BiometricType> availableBiometric;

  try{

    availableBiometric = await auth.getAvailableBiometrics();
  } on PlatformException catch (e){
    print(e);
  }
  setState(() {
    _availableBiometrics = availableBiometric;
  });
}

Future<void> _authenticate() async{
  bool authenticated = false;
  try{
    authenticated = await auth.authenticateWithBiometrics(
        localizedReason: "Scan your finger to authenticate",
        useErrorDialogs: true,
        stickyAuth: false
    );
  } on PlatformException catch(e){
    print(e);
  }

  if (!mounted) return;

  setState(() {
    autherized = authenticated ? "Autherized success":"Failed to authenticate";
    if(authenticated){
      Navigator.push(context,MaterialPageRoute(builder: (context) => SecondPage()));
    }

    print(autherized);
  });
}


@override

void initState(){
  _checkBiometric();
  _getAvailableBiometric();
}









@override
Widget build(BuildContext context) {
 return SafeArea(
    child: Scaffold(
     backgroundColor: Color(0xFF07496D),
     body: Padding(
       padding: const EdgeInsets.symmetric(vertical: 12.0, horizontal: 24.0),
       child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          Center(
            child: Text("Login",style: TextStyle(
                color: Colors.white,
                fontSize: 48.0,
                fontWeight: FontWeight.bold

            ),),
          ),
          Container(
              margin: EdgeInsets.symmetric(vertical: 50.0),
              child: Column(
                  children: <Widget>[
                    Image.asset(
                      'assets/fingerprint.png',
                      width: 120.0,
                    ),
                    Text("Fingerprint Auth", style: TextStyle(
                      color: Colors.white,
                      fontSize: 22.0,
                      fontWeight: FontWeight.bold,
                    ),),
                    Container(
                      width: 150.0,
                      margin: EdgeInsets.symmetric(vertical: 15.0),
                      child: Text("Authenticate with your fingerprint instead of your password",
                        textAlign: TextAlign.center,
                        style: TextStyle(
                          color: Colors.white,
                          height: 1.5,
                        ),
                      ),
                    ),
                    Container(
                        margin: EdgeInsets.symmetric(vertical: 15.0 ),
                        width: double.infinity,
                        child: RaisedButton(
                            onPressed: _authenticate,
                            elevation: 0.0,
                            color: Color(0xFF04A5ED),
                            shape: RoundedRectangleBorder(
                              borderRadius: BorderRadius.circular(30.0),
                            ),
                            child: Padding(
                              padding: EdgeInsets.symmetric(vertical:14.0,horizontal: 24.0),
                              child: Text("Authenticate", style: TextStyle(
                                color: Colors.white,
                              ),),
                            )
                        )
                    )
                  ]
              )
          )
        ],
      ),
     ) ,
    ),
  );
 }

}

androidManifest.xml

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

    <uses-permission android:name="android.permission.USE_FINGERPRINT"></uses-permission>

    
   <application
        android:label="fingerprint"
        android:icon="@mipmap/ic_launcher">
        <activity
            android:name=".MainActivity"
            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">
            <!-- Specifies an Android theme to apply to this Activity as soon as
                 the Android process has started. This theme is visible to the user
                 while the Flutter UI initializes. After that, this theme continues
                 to determine the Window background behind the Flutter UI. -->
            <meta-data
              android:name="io.flutter.embedding.android.NormalTheme"
              android:resource="@style/NormalTheme"
              />
            <!-- Displays an Android View that continues showing the launch screen
                 Drawable until Flutter paints its first frame, then this splash
                 screen fades out. A splash screen is useful to avoid any visual
                 gap between the end of Android's launch screen and the painting of
                 Flutter's first frame. -->
            <meta-data
              android:name="io.flutter.embedding.android.SplashScreenDrawable"
              android:resource="@drawable/launch_background"
              />
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <!-- Don't delete the meta-data below.
             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
        <meta-data
            android:name="flutterEmbedding"
            android:value="2" />
    </application>
</manifest>

pubspec.yaml

version: 1.0.0+1

environment:
  sdk: ">=2.7.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter


  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^1.0.2
  local_auth: ^0.4.0+1

当我运行这个应用程序时，它需要一个指纹并接受我移动到另一个页面。但是有什么方法可以读取 sha256 或 sha1 中的指纹或字符串？我想将此指纹保存在文件中以备将来使用。

Answer 1

看看这个包biometric_storage

https://pub.dev/packages/biometric_storage