我的 Android studio flutter 项目开始出现找不到符号错误。

C:\Users\abc\AppData\Roaming\Pub\Cache\hosted\pub.dartlang.org\firebase_messaging-2.2.0\android\src\main\java\io\flutter\plugins\firebasemessaging\FirebaseMe**ssagingPlugin.java:13: error: cannot find symbol
import androidx.annotation.NonNull;**
                          ^
  symbol:   class NonNull
  location: package androidx.annotation
C:\Users\abc\AppData\Roaming\Pub\Cache\hosted\pub.dartlang.org\firebase_messaging-2.2.0\android\src\main\java\io\flutter\plugins\firebasemessaging\FirebaseMessagingPlugin.java:14: error: package androidx.localbroadcastmanager.content does not exist
import androidx.localbroadcastmanager.content.LocalBroadcastManager;
                                             ^
C:\Users\abc\AppData\Roaming\Pub\Cache\hosted\pub.dartlang.org\firebase_messaging-2.2.0\android\src\main\java\io\flutter\plugins\firebasemessaging\FlutterFir**ebaseInstanceIDService.java:9: error: package androidx.localbroadcastmanager.content does not exist
import androidx.localbroadcastmanager.content.LocalBroadcastManager;**

任何人都知道出了什么问题？

根据其他用户的建议，我尝试重构为 AndroidX，但即使它是 compileSdkVersion 28 仍然出现错误。我还尝试使缓存无效并重新启动 android studio。

Gradle.properties

最佳答案

如果您使用的是 cloud_firestore: ^0.9.0 更改以下内容

pubspec.yaml

将 firebase_core: '^0.3.0' 添加到依赖项

android/build.gradle

将 mavenLocal() 添加到 buildscripts.repositories 和 allprojects.repositories

将 classpath 'com.google.gms:google-services:4.2.0' 添加到 buildscript.dependencies

android/grandle.properties

添加 android.useAndroidX=true 和 android.enableJetifier=true

android/app/build.gradle

将 compileSdkVersion 更改为 28

将依赖项更改为

testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test:runner:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'

在底部添加 apply plugin: 'com.google.gms.google-services'

https://stackoverflow.com/questions/54375194/