获取 android 房间数据库 java.lang.IllegalArgumentException 的以下异常：@androidx.room.Database 未定义元素视图（）

Posted 2023-04-13

【中文标题】获取 android 房间数据库 java.lang.IllegalArgumentException 的以下异常：@androidx.room.Database 未定义元素视图（）

【英文标题】：Getting following exception for android room database java.lang.IllegalArgumentException: @androidx.room.Database does not define an element views()

【发布时间】：2020-03-15 05:21:12

【问题描述】：

android 房间数据库出现以下异常

java.lang.IllegalArgumentException：@androidx.room.Database 没有 定义一个元素views()

我试图在 SO 上搜索任何解决方案，但找不到任何解决方案。 谁能解释这个错误与什么有关？

我只在我的房间数据库中使用 java。我没有使用 kotlin。 库版本

roomVersion = '2.2.1'
archLifecycleVersion = '2.1.0'

定义Entities,Dao和一个扩展roomdatabase的类

public static TncWalletAppDatabase getDatabase(final Context context) 
    if (INSTANCE == null) 
        synchronized (TncWalletAppDatabase.class) 
            if (INSTANCE == null) 
                INSTANCE = Room.databaseBuilder(context.getApplicationContext(),
                        TncWalletAppDatabase.class, "tnc_app_database")
                        .addCallback(sRoomDatabaseCallback)
                        .allowMainThreadQueries()
                        .build();
            
        
    
    return INSTANCE;

这是我初始化数据库的方法。 非常感谢您对此的任何帮助。

数据库类：

@Database(entities = Merchant.class, MerchantProfile.class, Receipt.class, ReceiptItems.class,TncTransaction.class, version = 1)

public abstract class TncWalletAppDatabase extends RoomDatabase 

    private static TncWalletAppDatabase INSTANCE;

    public abstract MerchantDao mMerchantDao();

    public abstract MerchantProfileDao mMerchantProfileDao();

    public abstract ReceiptDao mReceiptDao();

    public abstract ReceiptItemsDao mReceiptItemsDao();

    public abstract TncTransactionDao mTncTransactionDao();


    public static TncWalletAppDatabase getDatabase(final Context context) 
        if (INSTANCE == null) 
            synchronized (TncWalletAppDatabase.class) 
                if (INSTANCE == null) 
                    INSTANCE = Room.databaseBuilder(context.getApplicationContext(),
                            TncWalletAppDatabase.class, "tnc_app_database")
                            .addCallback(sRoomDatabaseCallback)
                            .allowMainThreadQueries()
                            .build();
                
            
        
        return INSTANCE;
    

    private static RoomDatabase.Callback sRoomDatabaseCallback = new RoomDatabase.Callback() 

        @Override
        public void onCreate(@NonNull SupportSQLiteDatabase db) 
            super.onCreate(db);
            // database trigger for tnc_transaction table
            new CreateDatabaseTriggerOnTncTransaction().execute();
        

    ;



    private static class CreateDatabaseTriggerOnTncTransaction extends AsyncTask<Void, Void, Void> 

        @Override
        protected Void doInBackground(final Void... params) 
            /**
             * Create database trigger when the tnc transaction table is created.
             */
            SupportSQLiteDatabase supportSQLiteDatabase = INSTANCE.getOpenHelper().getWritableDatabase();
            if( supportSQLiteDatabase != null ) 
                String TABLE_NAME = "tnc_transaction";
                supportSQLiteDatabase.execSQL(
                        "CREATE TRIGGER IF NOT EXISTS delete_" + TABLE_NAME + "_logs_max " +
                                "BEFORE INSERT ON " + TABLE_NAME + " " +
                                "WHEN (SELECT COUNT(*) FROM " + TABLE_NAME + ") > "
                                + TncTransactionDao.MAX_ROW_COUNT +
                                " " + "   BEGIN DELETE FROM " + TABLE_NAME + " WHERE id  = "
                                + "(SELECT MIN(id) FROM " + TABLE_NAME + "); " +
                                "END;");
            
            return null;
        
    

【问题讨论】：

你能发一下你的TncWalletAppDatabase课程吗？

@GiorgosNeokleous 刚刚发布了我的数据库课程。

@Ameya721 你好，你找到解决这个问题的方法了吗？在我的情况下，当我尝试将我的房间库从 2.0.0-alpha1 -> 更新到 2.2.3

时，会引发相同的错误

【参考方案1】：

将此添加到您的 build.grade 文件中？

dependencies 
  def room_version = "2.2.5"

  implementation "androidx.room:room-runtime:$room_version"
  annotationProcessor "androidx.room:room-compiler:$room_version" // For Kotlin use kapt instead of annotationProcessor

参考# https://developer.android.com/training/data-storage/room