持续的Android会议室：AppDatabase_Impl不存在

Question

我的应用程式资料库类别

@Database(entities = {Detail.class}, version = Constant.DATABASE_VERSION)
public abstract class AppDatabase extends RoomDatabase {

    private static AppDatabase INSTANCE;

    public abstract FavoritesDao favoritesDao();

    public static AppDatabase getAppDatabase(Context context) {
        if (INSTANCE == null) {
            INSTANCE =
                    Room.databaseBuilder(context.getApplicationContext(), AppDatabase.class, Constant.DATABASE).allowMainThreadQueries().build();

                    //Room.inMemoryDatabaseBuilder(context.getApplicationContext(),AppDatabase.class).allowMainThreadQueries().build();
        }
        return INSTANCE;
    }

    public static void destroyInstance() {
        INSTANCE = null;
    }
}

Gradle lib：

 compile "android.arch.persistence.room:runtime:+"   
 annotationProcessor "android.arch.persistence.room:compiler:+"

当我问例如它将给出此错误时，AppDatabase_Impl在我的应用程序类中不存在

public class APp extends Application {

    private boolean appRunning = false;

    @Override
    public void onCreate() {
        super.onCreate();
        AppDatabase.getAppDatabase(this); //--AppDatabase_Impl does not exist

    }

}

Answer 1

对于那些使用 Kotlin的人 ，请尝试在应用中更改annotationProcessor为kapt``build.gradle

例如：

// Extensions = ViewModel + LiveData
implementation "android.arch.lifecycle:extensions:1.1.0"
kapt "android.arch.lifecycle:compiler:1.1.0"
// Room
implementation "android.arch.persistence.room:runtime:1.0.0"
kapt "android.arch.persistence.room:compiler:1.0.0"

还记得添加这个插件

apply plugin: 'kotlin-kapt'

到应用程序级别build.gradle文件的顶部，然后进行清理和重建（根据https://codelabs.developers.google.com/codelabs/android-
room-with-a-
view/#6进行

）

在Android Studio中，如果在粘贴代码时或在构建过程中出现错误，请选择Build> Clean Project。然后选择Build>
Rebuild Project，然后再次进行构建。

如果您已迁移到androidx

def room_version = "2.2.3" // check latest version from docs

implementation "androidx.room:room-runtime:$room_version"
kapt "androidx.room:room-compiler:$room_version"