android-architecture-components

问题 I'm trying to create an app which will use MVVM architecture and there's one thing I quite don't understand. Official Android docs say that's not a good idea to reference activity context in ViewModel's (as ViewModel may outlive activity) so I've started to wonder about usecase when I want to execute some action when my activity is resumed. I know ViewModel's shouldn't do business logic themselves but even if I use some service class (let's say GPSService which has to start and pauseeach time

问题 I'm trying to create an app which will use MVVM architecture and there's one thing I quite don't understand. Official Android docs say that's not a good idea to reference activity context in ViewModel's (as ViewModel may outlive activity) so I've started to wonder about usecase when I want to execute some action when my activity is resumed. I know ViewModel's shouldn't do business logic themselves but even if I use some service class (let's say GPSService which has to start and pauseeach time

问题 I'm trying to create an app which will use MVVM architecture and there's one thing I quite don't understand. Official Android docs say that's not a good idea to reference activity context in ViewModel's (as ViewModel may outlive activity) so I've started to wonder about usecase when I want to execute some action when my activity is resumed. I know ViewModel's shouldn't do business logic themselves but even if I use some service class (let's say GPSService which has to start and pauseeach time

问题 I'm trying to create an app which will use MVVM architecture and there's one thing I quite don't understand. Official Android docs say that's not a good idea to reference activity context in ViewModel's (as ViewModel may outlive activity) so I've started to wonder about usecase when I want to execute some action when my activity is resumed. I know ViewModel's shouldn't do business logic themselves but even if I use some service class (let's say GPSService which has to start and pauseeach time

问题 I can't seem to find a clear answer to this in Google, and all the documentation and samples I've seen for Jetpack seem to refer to and use Kotlin. But do you HAVE to use Kotlin in order to use Jetpack? Or can Jetpack be used with traditional Java programs? I was looking at Kotlin but it adds almost a MB to your app size. And seeing as my entire app is only about 200KB currently, I don't think Kotlin is worth increasing the size of my app by 500%! 回答1: Jetpack is a collection of libraries

问题 public class FlightViewModel extends BaseViewModel { private FlightRepository flightRepository; private MediatorLiveData<Resource<FlightSearchMainOuterModel>> mSearchFlights = new MediatorLiveData<>(); private MediatorLiveData<Resource<FlightSearchMainOuterModel>> mOriginalList = new MediatorLiveData<>(); private MediatorLiveData<Resource<FlightSearchMainOuterModel>> mSortedSearchFlights = new MediatorLiveData<>(); public FlightViewModel(@NonNull Application application) { super(application);

问题 I was wondering if someone could either point me to documentation to / clarify when to create or destroy a room database instance. Also how you would effectively open / close it ? If I have a RoomDatabase object that gets injected via dagger to a presenter is that cool and then I just access various Daos? I'm worried about having the object lingering and taking up memory. 回答1: Instead of Injecting the RoomDatabase into your presenter you could Inject a DataManager Singleton class. This

问题 So, I have a really weird issue, I pass an object from Fragment A to Fragment B , I modify this object in a new instance in Fragment B, but after I change a value on this object it also changes that value when I pop Framgment B and that object keeps modified now also for Fragment A Fragment A ... override fun onItemClick(v: View?, position: Int) { searchView.clearFocus() val bundle = Bundle() bundle.putSerializable("shop", landingAdapter.getItem(position)) findNavController().navigate(R.id

问题 So, I have a really weird issue, I pass an object from Fragment A to Fragment B , I modify this object in a new instance in Fragment B, but after I change a value on this object it also changes that value when I pop Framgment B and that object keeps modified now also for Fragment A Fragment A ... override fun onItemClick(v: View?, position: Int) { searchView.clearFocus() val bundle = Bundle() bundle.putSerializable("shop", landingAdapter.getItem(position)) findNavController().navigate(R.id

问题 So, I have a really weird issue, I pass an object from Fragment A to Fragment B , I modify this object in a new instance in Fragment B, but after I change a value on this object it also changes that value when I pop Framgment B and that object keeps modified now also for Fragment A Fragment A ... override fun onItemClick(v: View?, position: Int) { searchView.clearFocus() val bundle = Bundle() bundle.putSerializable("shop", landingAdapter.getItem(position)) findNavController().navigate(R.id