android - 从图像 flutter firebase 进行文本识别

Question

我想检测图像中的文本，但每次运行程序时都会出现此错误，我尝试更改 firebase 的版本但徒劳无功，而且我还尝试将我的项目迁移到 androidx

E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037): java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.inwi.inwi_app. Make sure to call FirebaseApp.initializeApp(Context) first.
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at com.google.firebase.FirebaseApp.getInstance(com.google.firebase:firebase-common@@17.0.0:234)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at com.google.firebase.ml.vision.FirebaseVision.getInstance(Unknown Source)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at io.flutter.plugins.firebasemlvision.FirebaseMlVisionPlugin.handleDetection(FirebaseMlVisionPlugin.java:83)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at io.flutter.plugins.firebasemlvision.FirebaseMlVisionPlugin.onMethodCall(FirebaseMlVisionPlugin.java:45)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:222)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:96)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:643)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at android.os.MessageQueue.nativePollOnce(Native Method)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at android.os.MessageQueue.next(MessageQueue.java:323)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at android.os.Looper.loop(Looper.java:136)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at android.app.ActivityThread.main(ActivityThread.java:6682)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at java.lang.reflect.Method.invoke(Native Method)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1520)
E/MethodChannel#plugins.flutter.io/firebase_ml_vision(30037):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1410)
E/flutter (30037): [ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: PlatformException(error, Default FirebaseApp is not initialized in this process com.inwi.inwi_app. Make sure to call FirebaseApp.initializeApp(Context) first., null)
E/flutter (30037): #0      StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:564:7)
E/flutter (30037): #1      MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:316:33)
E/flutter (30037): <asynchronous suspension>
E/flutter (30037): #2      MethodChannel.invokeMapMethod (package:flutter/src/services/platform_channel.dart:344:48)
E/flutter (30037): <asynchronous suspension>
E/flutter (30037): #3      TextRecognizer.processImage (package:firebase_ml_vision/src/text_recognizer.dart:40:38)
E/flutter (30037): <asynchronous suspension>
E/flutter (30037): #4      HomePage.readText (package:inwi_app/HomePage.dart:29:47)
E/flutter (30037): <asynchronous suspension>
E/flutter (30037): #5      _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:635:14)
E/flutter (30037): #6      _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:711:32)
E/flutter (30037): #7      GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24)
E/flutter (30037): #8      TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:365:11)
E/flutter (30037): #9      TapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:275:7)
E/flutter (30037): #10     PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:455:9)
E/flutter (30037): #11     PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:75:13)
E/flutter (30037): #12     PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:102:11)
E/flutter (30037): #13     _WidgetsFlutterBinding&BindingBase&GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:218:19)
E/flutter (30037): #14     _WidgetsFlutterBinding&BindingBase&GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:198:22)
E/flutter (30037): #15     _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:156:7)
E/flutter (30037): #16     _WidgetsFlutterBinding&BindingBase&GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:102:7)
E/flutter (30037): #17     _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7)
E/flutter (30037): #18     _rootRunUnary (dart:async/zone.dart:1136:13)
E/flutter (30037): #19     _CustomZone.runUnary (dart:async/zone.dart:1029:19)
E/flutter (30037): #20     _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
E/flutter (30037): #21     _invoke1 (dart:ui/hooks.dart:250:10)
E/flutter (30037): #22     _dispatchPointerDataPacket (dart:ui/hooks.dart:159:5)

这是我的 pubspec.yml

name: inwi_app
description: A new Flutter application.

# The following defines the version and build number for your application.
# A version number is three numbers separated by dots, like 1.2.43
# followed by an optional build number separated by a +.
# Both the version and the builder number may be overridden in flutter
# build by specifying --build-name and --build-number, respectively.
# In Android, build-name is used as versionName while build-number used as versionCode.
# Read more about Android versioning at https://developer.android.com/studio/publish/versioning
# In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
# Read more about iOS versioning at
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
version: 1.0.0+1

environment:
  sdk: ">=2.1.0 <3.0.0"

dependencies:
  cloud_firestore:
  flutter:
    sdk: flutter


  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^0.1.2

dev_dependencies:
  flutter_test:
    sdk: flutter
  image_picker:
  firebase_ml_vision:



# For information on the generic Dart part of this file, see the
# following page: https://dart.dev/tools/pub/pubspec

# The following section is specific to Flutter.
flutter:

  # The following line ensures that the Material Icons font is
  # included with your application, so that you can use the icons in
  # the material Icons class.
  uses-material-design: true

  # To add assets to your application, add an assets section, like this:
  # assets:
  #  - images/a_dot_burr.jpeg
  #  - images/a_dot_ham.jpeg

  # An image asset can refer to one or more resolution-specific "variants", see
  # https://flutter.dev/assets-and-images/#resolution-aware.

  # For details regarding adding assets from package dependencies, see
  # https://flutter.dev/assets-and-images/#from-packages

  # To add custom fonts to your application, add a fonts section here,
  # in this "flutter" section. Each entry in this list should have a
  # "family" key with the font family name, and a "fonts" key with a
  # list giving the asset and other descriptors for the font. For
  # example:
  # fonts:
  #   - family: Schyler
  #     fonts:
  #       - asset: fonts/Schyler-Regular.ttf
  #       - asset: fonts/Schyler-Italic.ttf
  #         style: italic
  #   - family: Trajan Pro
  #     fonts:
  #       - asset: fonts/TrajanPro.ttf
  #       - asset: fonts/TrajanPro_Bold.ttf
  #         weight: 700
  #
  # For details regarding fonts from package dependencies,
  # see https://flutter.dev/custom-fonts/#from-packages

和我的build.gradle

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new GradleException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

apply plugin: 'com.android.application'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"

android {
    compileSdkVersion 28

    lintOptions {
        disable 'InvalidPackage'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.inwi.inwi_app"
        minSdkVersion 16
        targetSdkVersion 28
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        multiDexEnabled true
    }

    buildTypes {
        release {
            // TODO: Add your own signing config for the release build.
            // Signing with the debug keys for now, so `flutter run --release` works.
            signingConfig signingConfigs.debug
        }
    }
}

flutter {
    source '../..'
}

dependencies {
    implementation 'androidx.multidex:multidex:2.0.0'

    api 'com.google.firebase:firebase-ml-vision-image-label-model:18.0.0'

    implementation 'androidx.multidex:multidex:2.0.1'
    //implementation 'com.google.firebase:firebase-ml-vision:22.0.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.0'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.0'
}

请有人帮我，我已经尝试解决了将近 2 天

Answer 1

我想您还没有将您的应用程序与 firebase 连接起来。将您的项目添加到 firebase，并按照控制台中的说明将 google-services.json 添加到您的应用程序。只有这样，您的应用才能成功调用 firebase_ml_vision API。