Android SqlDelight和SqlBrite无缝结合使用的Demo例子

Android SqlDelight详解和Demo例子: 点我

Android SqlBrite使用介绍和官方demo详解: 点我

Android AutoValue使用和扩展库: 点我

在说到SqlBrite的时候有介绍到它的官方的例子，官方的栗子是没有用到SqlDelight的。这里我在这个例子的基础上添加SqlDelight，实现SqlBrite和SqlDelight的无缝连接。

这里我偷个懒，fork了SqlBrite的源码，然后添加了Sqldelight的栗子的module，然后把Sqldelight和SqlBrite的代码都加了中文注释； 然后再写了了一个Module，在SqlBrite的sample的基础上无缝结合SqlDelight。

sqlbrite_sqldelight_sample的Github地址: https://github.com/tpnet/sqlbrite

结合前和结合后的对比

这里以sqlbrite_sqldelight_sample 和 sqlbrite_sample作为例子：

1. bean类对比

SqlBrite没有结合SqlDelight:

@AutoValue
public abstract class TodoList implements Parcelable {

public static final String TABLE = "todo_list";

public static final String ID = "_id";
public static final String NAME = "name";
public static final String ARCHIVED = "archived";

public abstract long id();

public abstract String name();

public abstract boolean archived();

//利用RXjava进行数据的获取，返回bean列表
public static Func1<Cursor, List<TodoList>> MAP = new Func1<Cursor, List<TodoList>>() {
@Override
public List<TodoList> call(final Cursor cursor) {
try {
List<TodoList> values = new ArrayList<>(cursor.getCount());

while (cursor.moveToNext()) {
long id = Db.getLong(cursor, ID);
String name = Db.getString(cursor, NAME);
boolean archived = Db.getBoolean(cursor, ARCHIVED);
values.add(new AutoValue_TodoList(id, name, archived));
}
return values;
} finally {
cursor.close();
}
}
};

//构建器，用来生成ContentValues
public static final class Builder {
private final ContentValues values = new ContentValues();

public Builder id(long id) {
values.put(ID, id);
return this;
}

public Builder name(String name) {
values.put(NAME, name);
return this;
}

public Builder archived(boolean archived) {
values.put(ARCHIVED, archived);
return this;
}

public ContentValues build() {
return values; // TODO defensive copy?
}
}
}

SqlBrite结合了SqlDelight之后:

@AutoValue
public abstract class TodoList implements TodoListModel,Parcelable {

public abstract class TodoList implements TodoListModel,Parcelable {

public final static Factory<TodoList> FACTORY = new Factory<>(new  TodoListModel.Creator<TodoList>() {
@Override
public TodoList create(long _id, @NonNull String name, @Nullable String archived) {
return new AutoValue_TodoList(_id, name, archived);

}

});

@AutoValue
public abstract static class ListsItem implements Parcelable, List_queryModel {

}

public static Func1<Cursor, ListsItem> LIST_ITEM_FUNC = new Func1<Cursor, ListsItem>() {
@Override
public ListsItem call(Cursor cursor) {
return LIST_ITEM_MAPPER.map(cursor);
}
};

//查询title映射
public final static RowMapper<String> ROW_TITLE_MAPPER = FACTORY.title_queryMapper();

public final static RowMapper<ListsItem> LIST_ITEM_MAPPER = FACTORY.list_queryMapper(new List_queryCreator<ListsItem>() {
@Override
public ListsItem create(long _id, @NonNull String name, long item_count) {
return new AutoValue_TodoList_ListsItem(_id, name, item_count);
}
});

}

}

可以看到: 结合后的bean我们写的代码量少了，组合ContentValues这些事情不用我们手动做了，解析cursor不用我们手动做了，各种操作对象可以放在这里。

2. SQLiteOpenHelper类对比

结合前:

final class DbOpenHelper extends SQLiteOpenHelper {
private static final int VERSION = 1;

//创建todo_list表的语句
private static final String CREATE_LIST = ""
+ "CREATE TABLE " + TodoList.TABLE + "("
+ TodoList.ID + " INTEGER NOT NULL PRIMARY KEY,"
+ TodoList.NAME + " TEXT NOT NULL,"
+ TodoList.ARCHIVED + " INTEGER NOT NULL DEFAULT 0"
+ ")";

//创建todo_item表的语句
private static final String CREATE_ITEM = ""
+ "CREATE TABLE " + TodoItem.TABLE + "("
+ TodoItem.ID + " INTEGER NOT NULL PRIMARY KEY,"
+ TodoItem.LIST_ID + " INTEGER NOT NULL REFERENCES " + TodoList.TABLE + "(" + TodoList.ID + "),"
+ TodoItem.DESCRIPTION + " TEXT NOT NULL,"
+ TodoItem.COMPLETE + " INTEGER NOT NULL DEFAULT 0"
+ ")";

//创建 单列索引，加速查询
private static final String CREATE_ITEM_LIST_ID_INDEX =
"CREATE INDEX item_list_id ON " + TodoItem.TABLE + " (" + TodoItem.LIST_ID + ")";

//构造器，创建数据库
public DbOpenHelper(Context context) {
super(context, "todo.db", null /* factory */, VERSION);
}

//创建数据库的时候回调
@Override
public void onCreate(SQLiteDatabase db) {
//创建对应的表和索引
db.execSQL(CREATE_LIST);
db.execSQL(CREATE_ITEM);
db.execSQL(CREATE_ITEM_LIST_ID_INDEX);

//插入数据到todo_list表,返回id
long groceryListId = db.insert(TodoList.TABLE, null, new TodoList.Builder()
.name("Grocery List")
.build());

//根据todo_list表的id，插入数据到todo_item表，
db.insert(TodoItem.TABLE, null, new TodoItem.Builder()
.listId(groceryListId)
.description("Beer")
.build());
db.insert(TodoItem.TABLE, null, new TodoItem.Builder()
.listId(groceryListId)
.description("Point Break on DVD")
.build());
db.insert(TodoItem.TABLE, null, new TodoItem.Builder()
.listId(groceryListId)
.description("Bad Boys 2 on DVD")
.build());

....(和上面的套路一样这里省略了)

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}

结合后:

final class DbOpenHelper extends SQLiteOpenHelper {
private static final int VERSION = 1;

//构造器，创建数据库
public DbOpenHelper(Context context) {
super(context, "todo.db", null /* factory */, VERSION);
}

//创建数据库的时候回调
@Override
public void onCreate(SQLiteDatabase db) {
//创建对应的表和索引
db.execSQL(TodoList.CREATE_TABLE);
db.execSQL(TodoItem.CREATE_TABLE);
db.execSQL(CREATE_ITEM_LIST_ID_INDEX);

//初始化插入实体
TodoList.Insert_list insertList = new TodoListModel.Insert_list(db);
TodoItem.Insert_item insertItem = new TodoItemModel.Insert_item(db);

//插入数据到todo_list表,返回id
insertList.bind("Grocery List", "0");
long groceryListId = insertList.program.executeInsert();

//根据todo_list表的id，插入数据到todo_item
insertItem.bind(groceryListId, "Beer", false);
insertItem.program.executeInsert();

insertItem.bind(groceryListId, "Point Break on DVD", false);
insertItem.program.executeInsert();

insertItem.bind(groceryListId, "Bad Boys 2 on DVD", false);
insertItem.program.executeInsert();

...(和上面的套路一样,这里省略)

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}

可以看到： 结合后的SQLiteOpenHelper sql语句不用组合放在这里，清晰多了； 创表语句放在sq文件中,在自动生成的model，也可以得到创表的语句； 插增删改查利用bind来实现，更方便了，不用自己组合ContentValue，逻辑清晰，代码简介。

3. 查询对比

结合前:

subscription = db.createQuery(ListsItem.TABLES, ListsItem.QUERY)
.mapToList(ListsItem.MAPPER)   //映射到ListItem的MAPPER
.observeOn(AndroidSchedulers.mainThread()) //设置订阅者在主线程进行
.subscribe(adapter);

static Func1<Cursor, ListsItem> MAPPER = new Func1<Cursor, ListsItem>() {
@Override
public ListsItem call(Cursor cursor) {
long id = Db.getLong(cursor, TodoList.ID);
String name = Db.getString(cursor, TodoList.NAME);
int itemCount = Db.getInt(cursor, ITEM_COUNT);
return new AutoValue_ListsItem(id, name, itemCount);
}
};

结合后:

//创建查询
SqlDelightStatement sqLiteStatement = TodoList.FACTORY.list_query();

subscription = db.createQuery(TodoList.TABLE_NAME, sqLiteStatement.statement, sqLiteStatement.args)
.mapToList(TodoList.LIST_ITEM_FUNC)   //映射到ListItem的MAPPER
.observeOn(AndroidSchedulers.mainThread()) //设置订阅者在主线程进行
.subscribe(adapter);

public static Func1<Cursor, ListsItem> MAPPER = new Func1<Cursor, ListsItem>() {
@Override
public ListsItem call(Cursor cursor) {
return LIST_ITEM_MAPPER.map(cursor);
}
};

可以看到结合后的Curor解析不用我们手动解析，对应的查询语句和参数可以在SqlDelightStatement获取。

4. 更新添加对比

结合前：

Observable.combineLatest(createClicked, RxTextView.textChanges(name),
new Func2<String, CharSequence, String>() {
@Override
public String call(String ignored, CharSequence text) {
return text.toString();
}
}) //
.observeOn(Schedulers.io())
.subscribe(new Action1<String>() {
@Override
public void call(String description) {
db.insert(TodoItem.TABLE,
new TodoItem.Builder().listId(getListId()).description(description).build());
}
});

结合后:

Observable.combineLatest(createClicked, RxTextView.textChanges(name),
new Func2<String, CharSequence, String>() {
@Override
public String call(String ignored, CharSequence text) {
return text.toString();
}
}) //
.observeOn(Schedulers.io())
.subscribe(new Action1<String>() {
@Override
public void call(String description) {

//初始化插入对象
TodoItemModel.Insert_item insertItem = new TodoItemModel.Insert_item(db.getWritableDatabase());

//填入数据
insertItem.bind(getListId(), description, false);
//开始插入，这里会Rxjava会异步回调，进行更新列表
db.executeInsert(insertItem.table, insertItem.program);

//注意这里不要使用下面的插入代码，会导致Rxjava不能异步回调发送数据
//insertItem.program.executeInsert();

}
});

可以看到结合后：利用了SqlDelight生成的对应的Model类进行更新插入，不需要自己编写ContentValue，更方便的插入。

当然还有其他的变化。大家可以看看源码。