当我尝试在我的 flutter 应用程序中使用 firebase_Auth 时出现问题

Question

i'm new to flutter and wants to integrate my app with firebase. I copy the code from this site ( https://www.developerlibs.com/2018/11/flutter-firebase-realtime-database-crud.html ). And here is my code's link, link of Git. https://github.com/hannan228/flutter-with-firebase.git

pubspec.yaml code is here pubspec.yaml code name: databaseinflutter description: A new Flutter application.

publish_to: 'none' # Remove this line if you wish to publish to pub.dev

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: ^0.1.3
  firebase_database: ^1.0.5
  http: "^0.11.3+17"
  firebase_auth: 0.16.1
  #firebase_auth: 0.6.2+1
  google_sign_in: ^3.2.1
  fluttertoast: ^2.0.7
  flutter_svg: ^0.6.1+1

dev_dependencies:
  flutter_test:
    sdk: flutter
# The following section is specific to Flutter.
flutter:
  uses-material-design: true

app/build.gradle is same as

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.google.gms.google-services'
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.yovin.databaseinflutter"
        minSdkVersion 23
        targetSdkVersion 28
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }

    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 {
    testImplementation 'junit:junit:4.13'
    androidTestImplementation 'androidx.test:runner:1.2.0'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'

    implementation 'com.android.support:multidex:1.0.3' //for multidex

    implementation 'com.google.firebase:firebase-analytics:17.4.3'
    implementation 'com.google.firebase:firebase-auth:19.3.1'
    implementation 'com.google.firebase:firebase-firestore:21.4.3'

}

android/build.gradle is as

    buildscript {
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.6.3'
        classpath 'com.google.gms:google-services:4.3.3'
    }
}
allprojects {
    repositories {
        google()
        jcenter()
    }
}
rootProject.buildDir = '../build'
subprojects {
    project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
    project.evaluationDependsOn(':app')
}

task clean(type: Delete) {
    delete rootProject.buildDir
}
apply plugin: 'com.google.gms.google-services'

here is GeneratedPluginRegistrant.java file

here is screenshot of some error

Following is complete errors that are showing in Console

Running Gradle task 'assembleDebug'... C:\flutter\flutter_windows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:8: error: package android.support.annotation does not exist import android.support.annotation.NonNull; ^ C:\flutter\flutter_windows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:538: error: cannot find symbol public void onComplete(@NonNull Task task) { ^ symbol: class NonNull location: class FirebaseAuthPlugin.SignInCompleteListener C:\flutter\flutter_windows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:558: error: cannot find symbol public void onComplete(@NonNull Task task) { ^ symbol: class NonNull location: class FirebaseAuthPlugin.TaskVoidCompleteListener C:\flutter\flutter_windows_1.17.4-stabl e\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:576: error: cannot find symbol public void onComplete(@NonNull Task task) { ^ symbol: class NonNull location: class FirebaseAuthPlugin.ProvidersCompleteListener C:\flutter\flutter_windows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:175: error: cannot find symbol public void onComplete(@NonNull Task task) { ^ symbol: class NonNull C:\flutter\flutter_windows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.Z93F725A07423FE1C889F 448B33D21F46Z:270: error: cannot find symbol public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) { ^ symbol: class NonNull C:\flutter\flutter_windows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:435: error: cannot find symbol public void onComplete(@NonNull Task task) { ^ symbol: class NonNull C:\flutter\flutter_windows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java:487: error: cannot find symbol public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) { ^ symbol: class NonNull Note: C:\flutter\flutter_w indows_1.17.4-stable\flutter.pub-cache\hosted\pub.dartlang.org\firebase_auth-0.6.2+1\android\src\main\java\io\flutter\plugins\firebaseauth\FirebaseAuthPlugin.java uses or overrides a deprecated API. Note: Recompile with -Xlint:deprecation for details. 8 errors

FAILURE: Build failed with an exception.

• What went wrong: Execution failed for task ':firebase_auth:compileDebugJavaWithJavac'.

Compilation failed; see the compiler error output for details.

• Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

• Get more help at https://help.gradle.org

BUILD FAILED in 1m 14s The built failed likely due to AndroidX incompatibilities in a plugin. The tool is about to try using Jetfier to solve the incompatibility. Building plugin firebase_auth... Running Gradle task 'assembleAarRelease'... √ Built build\app\outputs\repo. Building plugin firebase_core... Running Gradle task 'assembleAarRelease'... √ Built build\app\outputs\repo. Building plugin firebase_database... Running Gradle task 'assembleAarRelease'... √ Built build\app\outputs\repo. Building plugin fluttertoast... Running Gradle task 'assembleAarRelease'... √ Built build\app\outputs\repo. Building plugin google_sign_in... Running Gradle task 'assembleAarRelease'... √ Built build\app\outputs\repo. Running Gradle task 'assembleDebug'...

FAILURE: Build failed with an exception.

• What went wrong: Execution failed for task ':app:checkDebugDuplicateClasses'.

1 exception was raised by workers: java.lang.RuntimeException: Duplicate class com.google.android.gms.internal.measurement.zzu found in modules jetified-firebase-analytics-impl-16.2.2-runtime.jar (com.google.firebase:firebase-analytics-impl:16.2.2) and jetified-play-services-measurement-base-17.4.3-runtime.jar (com.google.android.gms:play-services-measurement-base:17.4.3)

BUILD FAILED in 3m 49s Exception: Gradle task assembleDebug failed with exit code 1

Answer 1

error: package android.support.annotation does not exist import android.support.annotation.NonNull;

The above error says that your project is made with androidx dependency but the problem is with auth package.

I can see you are using firebase_auth package of version 0.6.2 which is before the breaking change of "Migrating to AndroidX". Also in your Android dependencies

    testImplementation 'junit:junit:4.13'
    androidTestImplementation 'androidx.test:runner:1.2.0'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'

    implementation 'com.android.support:multidex:1.0.3'

you are mixing androidx and support libraries. Android support library nomenclature that is com.android.support:X is deprecated and should no longer be used and should be replaced by the newer androidx dependencies. Mixing the two with a very outdated package ( firebase_auth is currently at 0.16) will lead to such error.

In conclusion, your error should be resolved if you jumped your firebase_auth version to the latest ( firebase_auth 0.16.1 ) and replace multidex dependency to 'androidx.multidex:multidex:2.0.1

You can read more about AndroidX and Multidex here:

1. https://developer.android.com/jetpack/androidx/
2. What is AndroidX?
3. https://developer.android.com/studio/build/multidex

Hopefully, this solves your error. Drop a comment otherwise or edit your answer with the new error. INclude your pubsec.yaml file in case too