Mercury-IM/app/src/main/java/org/mercury_im/messenger/ui/roster/RosterViewModel.java

package org.mercury_im.messenger.ui.roster;

import androidx.lifecycle.LiveData;
import androidx.lifecycle.MutableLiveData;
import androidx.lifecycle.ViewModel;

import org.mercury_im.messenger.MercuryImApplication;
import org.mercury_im.messenger.persistence.repository.ContactRepository;
import org.mercury_im.messenger.persistence.room.model.RoomContactModel;
import org.mercury_im.messenger.persistence.room.repository.IContactRepository;

import java.util.List;

import javax.inject.Inject;

import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.disposables.CompositeDisposable;
import io.reactivex.schedulers.Schedulers;

public class RosterViewModel extends ViewModel {

    @Inject
    ContactRepository contactRepository;

    private final MutableLiveData<List<RoomContactModel>> rosterEntryList = new MutableLiveData<>();
    private final CompositeDisposable compositeDisposable = new CompositeDisposable();

    public RosterViewModel() {
        super();
        MercuryImApplication.getApplication().getAppComponent().inject(this);

        // Subscribe to changes to the contacts table and update the LiveData object for the UI.
        compositeDisposable.add(contactRepository.getAllContacts()
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(o -> rosterEntryList.setValue((List<RoomContactModel>) o)));
    }

    @Override
    protected void onCleared() {
        super.onCleared();
        compositeDisposable.clear();
    }

    public LiveData<List<RoomContactModel>> getRosterEntryList() {
        return rosterEntryList;
    }
}