Filter based on user input - LiveData, Recycler, RoomView - sqlite

Question

I have an SQLite Database for my Android App. Database has a table for properties , and another table for the repairs at each property.
Table repairs :
#Entity(tableName = "repairs",
indices = {#Index(value = "repairID", unique = true), #Index("repairPropID")})
public class MYRepairs
{
#PrimaryKey(autoGenerate = true)
#ColumnInfo(name = "repid")
public int id;
#ColumnInfo(name = "repairID")
#NonNull
public String repairID;
#ColumnInfo(name = "repairPropID")
public int repairPropID;
}
...
and then RepairsDao.java
#Dao
public interface MyRepairsDao
{
#Query("SELECT * FROM repairs WHERE repid = :repid LIMIT 1")
MYRepairs findRepairById(String repid);
#Query("SELECT * FROM repairs WHERE repairPropID = :repairPropID")
MYRepairs findRepairByPropID(int repairPropID);
#Query("SELECT * FROM repairs ORDER BY repairPropID ASC")
LiveData<List<MYRepairs>> getAllRepairs();
#Query("SELECT * FROM repairs WHERE repairPropID = :repairPropID")
LiveData<List<MYRepairs>> getPropertyRepairs(int repairPropID);
}
In the ViewModel:
public class repairViewModel extends AndroidViewModel
{
private MyRepairsDao myRepairDao;
private LiveData<List<MYRepairs>> repairLiveData;
private LiveData<List<MYRepairs>> repairPropertyLiveData;
private LiveData<String> filterLiveData = new MutableLiveData<String>();
public repairViewModel(#NonNull Application application)
{
super(application);
myRepairDao = DogwoodDatabase.getDatabase(application).repairDao();
repairLiveData = myRepairDao.getAllRepairs();
repairPropertyLiveData = myRepairDao.getPropertyRepairs(propertyID);
}
public LiveData<List<MYRepairs>> getAllRepairs()
{
return repairLiveData;
}
public LiveData<List<MYRepairs>> getPropertyRepairs(int propertyID)
{
return repairPropertyLiveData;
}
And in the RecyclerView.Adapter:
public class repairListAdapter extends RecyclerView.Adapter<repairListAdapter.RepairViewHolder>
{
#NonNull
#Override
public repairListAdapter.RepairViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType)
{
final View itemView = layoutInflater.inflate(R.layout.repaircontent, parent, false);
return new repairListAdapter.RepairViewHolder(itemView);
}
In the repairFragment - we only want to view the repairs for a user selected property. Property Code propertyID is received by the repairFragement. It is known to the initData()
public class repairFragment extends Fragment
{
private repairListAdapter repairListAdapter;
private repairViewModel repairViewModel;
public void onCreate(#Nullable Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
propertyID = getArguments().getString("ARG_PROPNUM_ID");
propNumID = Integer.parseInt(propertyID);
initData();
}
private void initData()
{
Log.e ("INIT", "ID is " + propertyID);
repairViewModel = new
ViewModelProvider(this).get(repairViewModel.class);
repairViewModel.getPropertyRepairs(propertyID).observe(this, new Observer<List<MYRepairs>>()
{
#Override
public void onChanged(#Nullable List<MYRepairs> MYRepairs)
{
repairListAdapter.setMYRepairList(MYRepairs);
}
});
}
This returns NO RECORDS.
In an ideal world, my properties would have no repairs, but I do not live in that world!
I have scoured this board for help on filtering .
Can you help me with how to filter for only the repairs for a user selected property (propertyID).
Thanks, Rachael

Answer 1

What you wanted to do is the following:
public LiveData<List<MYRepairs>> getPropertyRepairs() {
return repairPropertyLiveData;
}
And
private MutableLiveData<String> selectedPropertyId = new MutableLiveData<>();
private final repairPropertyLiveData = Transformations.switchMap(selectedPropertyId, (id) -> {
return myRepairDao.getPropertyRepairs(id);
});
public void updateSelectedProperty(String propertyId) {
selectedPropertyId.setValue(propertyId);
}
This way, you don't end up with new subscriptions that were not properly invalidated in case you were to select a different property id later.

Answer 2

Oh my! I figured it out.
In repairViewModel:
public LiveData<List<MYRepairs>> getPropertyRepairs(int propertyID)
{
repairPropertyLiveData = myRepairDao.getPropertyRepairs(propertyID);
return repairPropertyLiveData;
}