Android Room的使用详解

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我是靠谱客的博主动听凉面，最近开发中收集的这篇文章主要介绍Android Room的使用详解，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

1、导入配置

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

      // optional - Kotlin Extensions and Coroutines support for Room
      implementation "androidx.room:room-ktx:$room_version"

      // optional - RxJava support for Room
      implementation "androidx.room:room-rxjava2:$room_version"

      // optional - Guava support for Room, including Optional and ListenableFuture
      implementation "androidx.room:room-guava:$room_version"

      // Test helpers
      testImplementation "androidx.room:room-testing:$room_version"
    }

2、创建表

    @Entity
    public class User {
        @PrimaryKey
        public int uid;

        @ColumnInfo(name = "first_name")
        public String firstName;

        @ColumnInfo(name = "last_name")
        public String lastName;
    }

参考：developer.android.google.cn/training/da…

3、创建Dao

包含访问数据库的一系列方法。

    @Dao
    public interface UserDao {
        @Query("SELECT * FROM user")
        List<User> getAll();

        @Query("SELECT * FROM user WHERE uid IN (:userIds)")
        List<User> loadAllByIds(int[] userIds);

        @Query("SELECT * FROM user WHERE first_name LIKE :first AND " +
               "last_name LIKE :last LIMIT 1")
        User findByName(String first, String last);

        @Insert
        void insertAll(User... users);
        
        @Insert
        void insert(User user);

        @Delete
        void delete(User user);
    }

参考：developer.android.google.cn/training/da…

4、创建数据库

    @Database(entities = {User.class}, version = 1)
    public abstract class AppDatabase extends RoomDatabase {
        public abstract UserDao userDao();
    }

5、使用

    AppDatabase db = Room.databaseBuilder(getApplicationContext(),
            AppDatabase.class, "database-name").build();
    db.userDao().insert(new User());

以上就是Android Room的使用详解的详细内容，更多关于Android Room的使用的资料请关注靠谱客其它相关文章！