插件 flutter_plugin_android_lifecycle 无法构建

Question

任务 - :compileReleaseJavaWithJavac 失败说：由于错误，无法构建插件 flutter_plugin_android_lifecycle：

error: package androidx.lifecycle does not exist
import androidx.lifecycle.Lifecycle;

和

error: cannot find symbol
  public static Lifecycle getActivityLifecycle(
                ^
  symbol:   class Lifecycle
  location: class FlutterLifecycleAdapter

这是 FlutterLifecycleAdapter.java 文件：

package io.flutter.embedding.engine.plugins.lifecycle;

import androidx.annotation.NonNull;
import androidx.lifecycle.Lifecycle;
import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding;

/** Provides a static method for extracting lifecycle objects from Flutter plugin bindings. */
public class FlutterLifecycleAdapter {
  private static final String TAG = "FlutterLifecycleAdapter";

  /**
   * Returns the lifecycle object for the activity a plugin is bound to.
   *
   * <p>Returns null if the Flutter engine version does not include the lifecycle extraction code.
   * (this probably means the Flutter engine version is too old).
   */
  @NonNull
  public static Lifecycle getActivityLifecycle(
      @NonNull ActivityPluginBinding activityPluginBinding) {
    HiddenLifecycleReference reference =
        (HiddenLifecycleReference) activityPluginBinding.getLifecycle();
    return reference.getLifecycle();
  }
}

这是我第一次使用 sharedPreferences 和 Flutter_secure_storage，也是我第一次遇到这个问题。我相信更新 Android Studio 后会出现错误。我没有触及此文件中的任何内容。提前感谢您的帮助！

Answer 1

请按照以下步骤操作：

在gradle-wrapper.properties中添加以下代码：

distributionUrl=https://services.gradle.org/distributions/gradle-5.4.1-all.zip

在gradle.properites中请检查是否添加了以下行：

android.useAndroidX=true
android.enableJetifier=true

在android/build.gradle文件中添加以下代码：

classpath 'com.android.tools.build:gradle:3.5.4'

并在android/build.gradle中检查此版本：

compileSdkVersion 29

请参阅此链接了解更多信息： clickhere