I want to open the data of a Firebase subcollection in a new RecyclerView. The Main Activity has a RecyclerView filled with the data from the first collection and a second activity should be opened through a click on one of the items.This second activity would have the second RecyclerView. My main Activity works fine and I can see all my data. But when I click on one of the items, my app crashes.
This is my MainActivity
private FirebaseFirestore db = FirebaseFirestore.getInstance();
private CollectionReference notebookRef = db.collection("Notebook");
private KisteAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FloatingActionButton buttonAddKiste = findViewById(R.id.button_add_kiste);
buttonAddKiste.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
startActivity(new Intent(MainActivity.this, NewKisteActivity.class));
}
});
setUpRecyclerView();
}
private void setUpRecyclerView(){
Query query = notebookRef.orderBy("priority", Query.Direction.DESCENDING);
FirestoreRecyclerOptions<Kiste> options = new FirestoreRecyclerOptions.Builder<Kiste>()
.setQuery(query, Kiste.class)
.build();
adapter = new KisteAdapter(options);
final RecyclerView recyclerView = findViewById(R.id.recycler_view_kiste);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(adapter);
new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT |ItemTouchHelper.RIGHT) {
@Override
public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
return false;
}
@Override
public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
adapter.deleteKiste(viewHolder.getAdapterPosition());
final DocumentReference docRef = adapter.getSnapshots().getSnapshot(viewHolder.getAdapterPosition()).getReference();
final Kiste kiste = adapter.getSnapshots().getSnapshot(viewHolder.getAdapterPosition()).toObject(Kiste.class);
Snackbar.make(recyclerView, "Item deleted", Snackbar.LENGTH_LONG)
.setAction("Undo", new View.OnClickListener() {
@Override
public void onClick(View v) {
docRef.set(kiste);
}
}).show();
}
@Override
public void onChildDraw(@NonNull Canvas c, @NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) {
new RecyclerViewSwipeDecorator.Builder(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive)
.addBackgroundColor(ContextCompat.getColor(MainActivity.this, R.color.colorAccent))
.addActionIcon(R.drawable.ic_delete_)
.create()
.decorate();
super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
}
}).attachToRecyclerView(recyclerView);
adapter.setOnKisteClickListen(new KisteAdapter.onItemClickListener() {
@Override
public void onKisteClick(DocumentSnapshot documentSnapshot, int position) {
final DocumentReference docRef = documentSnapshot.getReference();
final CollectionReference colRef = documentSnapshot.getReference().collection("A");
final Intent intent = new Intent(MainActivity.this,SecondaryActivity.class);
colRef.get().addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
@Override
public void onSuccess(QuerySnapshot queryDocumentSnapshots) {
if (queryDocumentSnapshots.isEmpty()){
colRef.add(new Item("DFB","SGRDG",5));
/*intent.putExtra("Document Reference",docRef.getId());
intent.putExtra("Collection Reference",colRef.getId());*/
startActivity(intent);
}
else {
startActivity(intent);
}
}
});
}
});
}
@Override
protected void onStart() {
super.onStart();
adapter.startListening();
}
@Override
protected void onStop() {
super.onStop();
adapter.stopListening();
}
}
this is the Class Kiste, which the first RecyclerView gets
public class Kiste {
private String title;
private int priority;
public Kiste(){
}
public Kiste(String title, int priority){
this.title= title;
this.priority = priority;
}
public String getTitle() {
return title;
}
public int getPriority() {
return priority;
}
}
And this is the adapter
public class KisteAdapter extends FirestoreRecyclerAdapter<Kiste, KisteAdapter.KisteHolder> {
private onItemClickListener listener;
public KisteAdapter(@NonNull FirestoreRecyclerOptions<Kiste> options) {
super(options);
}
@Override
protected void onBindViewHolder(@NonNull KisteHolder holder, int position, @NonNull Kiste model) {
holder.textViewTitle.setText(model.getTitle());
holder.textViewPriority.setText(String.valueOf(model.getPriority()));
}
@NonNull
@Override
public KisteHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.kiste_item,parent,false);
return new KisteHolder(v);
}
public void deleteKiste(int position){
getSnapshots().getSnapshot(position).getReference().delete();
}
class KisteHolder extends RecyclerView.ViewHolder{
TextView textViewTitle;
TextView textViewPriority;
public KisteHolder(@NonNull View itemView) {
super(itemView);
textViewTitle = itemView.findViewById(R.id.text_view_title);
textViewPriority = itemView.findViewById(R.id.text_view_priority);
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION && listener!= null){
listener.onKisteClick(getSnapshots().getSnapshot(position),position);
}
}
});
}
}
public interface onItemClickListener {
void onKisteClick(DocumentSnapshot documentSnapshot, int position);
}
public void setOnKisteClickListen (onItemClickListener listener) {this.listener = listener;}
}
Since that worked for me, I tried doing the same with the subcollection (As I was still testing if it would work, I just used one DocumentPath that I knew existed ) but as I said above the app keeps crashing.
Here is the secondActivity
public class SecondaryActivity extends AppCompatActivity {
private FirebaseFirestore db = FirebaseFirestore.getInstance();
private CollectionReference colRef = db.collection("Notebook").document(
"JGBzWBwCASivfAjuF8xE").collection("A");
private ItemAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_secondary);
FloatingActionButton buttonAddItem = findViewById(R.id.button_add_item);
setupRecyclerView();
}
private void setupRecyclerView(){
Query query2 = colRef.orderBy("priority", Query.Direction.DESCENDING);
FirestoreRecyclerOptions<Item> options = new FirestoreRecyclerOptions.Builder<Item>()
.setQuery(query2, Item.class)
.build();
adapter = new ItemAdapter(options);
final RecyclerView recyclerView = findViewById(R.id.recycler_view_item);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(adapter);
}
@Override
protected void onStart() {
super.onStart();
adapter.startListening();
}
@Override
protected void onStop() {
super.onStop();
adapter.stopListening();
}
}
the Class Item:
public class Item {
//private Bitmap imageItem;
private String itemName;
private String itemQuantity;
private int priority;
public Item(){
}
public Item( String itemName, String itemQuantity, int priority){
//this.imageItem = imageViewItem;
this.itemName = itemName;
this.itemQuantity = itemQuantity;
this.priority = priority;
}
/*public Bitmap getImageItem() {
return imageItem;
}*/
public String getItemName() {
return itemName;
}
public String getItemQuantity() {
return itemQuantity;
}
public int getPriority() {
return priority;
}
} and the adapter :
public class ItemAdapter extends FirestoreRecyclerAdapter<Item, ItemAdapter.ItemHolder> {
public ItemAdapter(@NonNull FirestoreRecyclerOptions<Item> options) {
super(options);
}
@Override
protected void onBindViewHolder(@NonNull ItemHolder holder, int position, @NonNull Item model) {
//holder.imageViewItem.setImageBitmap(model.getImageItem());
holder.textViewTitle.setText(model.getItemName());
holder.textViewQuantity.setText(model.getItemQuantity());
holder.textViewPriority.setText(String.valueOf(model.getPriority()));
}
@NonNull
@Override
public ItemHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_item,parent,false);
return new ItemHolder(v);
}
class ItemHolder extends RecyclerView.ViewHolder{
//ImageView imageViewItem;
TextView textViewTitle;
TextView textViewQuantity;
TextView textViewPriority;
public ItemHolder(@NonNull View itemView){
super(itemView);
//imageViewItem.findViewById(R.id.image_view_item);
textViewTitle.findViewById(R.id.text_view_item_name);
textViewQuantity.findViewById(R.id.text_view_item_quantity);
textViewPriority.findViewById(R.id.text_view_priority2);
}
}
}
I would really appreciate it if someone could help me figure out what the problem is.
Thanks for pointing out the error in the console, now it's much easier for us to see where the problem is without the need of reading your whole code :D
You're getting an error in line 47 of your ItemAdapter class. I can't see exactly which line it is, but I'm certain the error is inside your ViewHolder.
class ItemHolder extends RecyclerView.ViewHolder{
//ImageView imageViewItem;
TextView textViewTitle;
TextView textViewQuantity;
TextView textViewPriority;
public ItemHolder(@NonNull View itemView){
super(itemView);
//imageViewItem.findViewById(R.id.image_view_item);
THESE LINES OF CODE -----------------------------------------------------------------
textViewTitle.findViewById(R.id.text_view_item_name);
textViewQuantity.findViewById(R.id.text_view_item_quantity);
textViewPriority.findViewById(R.id.text_view_priority2);
-------------------------------------------------------------------------------------
}
}
replace them with:
this.textViewTitle = (TextView) itemView.findViewById(R.id.text_view_item_name); // and so on...
You can check out this example:
https://www.javatpoint.com/android-recyclerview-list-example