java我如何从Android中的Worker类访问我的Rooms数据库的存储库?
我在应用程序中有一个Worker
类,我想从我的房间数据库中获取数据。由于我使用的是MVVM体系结构,如何使用Worker
类中的存储库从数据库中获取数据
密码-
工人阶级
public class SendNotification extends Worker {
public SendNotification(@NonNull Context context, @NonNull WorkerParameters workerParams) {
super(context, workerParams);
}
@RequiresApi(api = Build.VERSION_CODES.M)
@NonNull
@Override
public Result doWork() {
String flightnumber = getInputData().getString("flight");
String date = getInputData().getString("date");
sendNotification(flightnumber,date);
return Result.success();
}}
存储库
public class FlightRepository {
private FlightDao flightDao;
private LiveData<List<Flight>> allFlights;
public FlightRepository(Application application) {
FlightDatabase database = FlightDatabase.getInstance(application);
flightDao = database.flightDao();
allFlights = flightDao.getAllFlights();
}
public void insert(Flight flight) {
new InsertFlightAsyncTask(flightDao).execute(flight);
}
public void update(Flight flight) {
new UpdateFlightAsyncTask(flightDao).execute(flight);
}
public void delete(Flight flight) {
new DeleteFlightAsyncTask(flightDao).execute(flight);
}
public void deleteAllFlights() {
new DeleteAllFlightsAsyncTask(flightDao).execute();
}
public LiveData<List<Flight>> getAllFlights() {
return allFlights;
}
public Flight getFlight(String flightNumber, String date){
return flightDao.getFlight(flightNumber,date);
}
public boolean existsFlight(String flightNumber, String date){
return flightDao.existsFlight(flightNumber, date);
}
# 1 楼答案
您应该能够在
Worker
内创建FlightRepository
的实例:在这里做一些假设。我会重构
FlightDatabase
来接受Context
,而不是Application
。我不确定数据库为什么需要访问Application