找不到符号公共无效配置FlutterEngine(@NonNull FlutterEngine FlutterEngin

Question

我在尝试在文件中注册插件时收到此错误MainActivity.java

错误日志

: error: cannot find symbol
public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
^

主活动.java

package com.orsac.bluis;
import io.flutter.embedding.android.FlutterActivity;
public class MainActivity extends FlutterActivity {   @Override   public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine) {
GeneratedPluginRegistrant.registerWith(flutterEngine);   }
}

在AndroidManifest.xml文件中，在android:name=".UniappApplication"和android:name=".MainActivity"中获取未解析的类错误

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.orsac.bluis">
<application
android:name=".UniappApplication" // Here
android:label="BLUIS"
android:usesCleartextTraffic="true"
android:networkSecurityConfig="@xml/network_security_config"
android:icon="@mipmap/ic_launcher">
<activity
android:name=".MainActivity" // Here
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">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
<intent-filter>
<action android:name="FLUTTER_NOTIFICATION_CLICK" />
<category android:name="android.intent.category.DEFAULT" />
</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>

我尝试过的事情

Flutter clean
Flutter run
Invalidate caches and restart

Answer 1

你应该导入androidx.annotation.NonNull;

import androidx.annotation.NonNull;

Answer 2

1- 更新targetSdkVersion并将SdkVersion编译为最新版本，并在android部分下的build.gradle(应用程序级别(中将SdkVersion编译为最新版本和同等版本

2-在主活动中导入这些库

import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.FlutterEngine;
import io.flutter.plugins.googlemobileads.GoogleMobileAdsPlugin;