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mRegistration = mQuery.addSnapshotListener(this);
"this" is getting me this error.
Error:(58, 56) error: incompatible types: FirestoreAdapter<VH> cannot be converted to EventListener<QuerySnapshot> where VH is a type-variable: VH extends ViewHolder declared in class FirestoreAdapter
NOTE: the interface EventLister is empty , so I just have to comment the
//@OverRide
public void onEvent(QuerySnapshot documentSnapshots, FirebaseFirestoreException e) {
Code bellow
/**
* Copyright 2017 Google Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.firebase.example.fireeats.adapter;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import com.google.firebase.firestore.DocumentChange;
import com.google.firebase.firestore.DocumentSnapshot;
import com.google.firebase.firestore.FirebaseFirestoreException;
import com.google.firebase.firestore.ListenerRegistration;
import com.google.firebase.firestore.Query;
import com.google.firebase.firestore.QuerySnapshot;
import java.util.ArrayList;
import java.util.EventListener;
/**
* RecyclerView adapter for displaying the results of a Firestore {@link Query}.
*
* Note that this class forgoes some efficiency to gain simplicity. For example, the result of
* {@link DocumentSnapshot#toObject(Class)} is not cached so the same object may be deserialized
* many times as the user scrolls.
*
* See the adapter classes in FirebaseUI (https://github.com/firebase/FirebaseUI-Android/tree/master/firestore) for a
* more efficient implementation of a Firestore RecyclerView Adapter.
*/
public abstract class FirestoreAdapter<VH extends RecyclerView.ViewHolder>
extends RecyclerView.Adapter<VH> implements EventListener {
private static final String TAG = "Firestore Adapter";
private Query mQuery;
private ListenerRegistration mRegistration;
private ArrayList<DocumentSnapshot> mSnapshots = new ArrayList<>();
public FirestoreAdapter(Query query) {
mQuery = query;
}
public void startListening() {
// TODO(developer): Implement
if (mQuery != null && mRegistration == null) {
mRegistration = mQuery.addSnapshotListener(this);
}
}
public void stopListening() {
if (mRegistration != null) {
mRegistration.remove();
mRegistration = null;
}
mSnapshots.clear();
notifyDataSetChanged();
}
public void setQuery(Query query) {
// Stop listening
stopListening();
// Clear existinkodig data
mSnapshots.clear();
notifyDataSetChanged();
// Listen to new query
mQuery = query;
startListening();
}
//@Override
public void onEvent(QuerySnapshot documentSnapshots, FirebaseFirestoreException e) {
// Handle errors
if (e != null) {
Log.w(TAG, "onEvent:error", e);
return;
}
// Dispatch the event
for (DocumentChange change : documentSnapshots.getDocumentChanges()) {
// Snapshot of the changed document
DocumentSnapshot snapshot = change.getDocument();
switch (change.getType()) {
case ADDED:
// TODO: handle document added
onDocumentAdded(change);
break;
case MODIFIED:
// TODO: handle document modified
onDocumentModified(change);
break;
case REMOVED:
// TODO: handle document removed
onDocumentRemoved(change);
break;
}
}
onDataChanged();
}
protected void onDocumentAdded(DocumentChange change){
mSnapshots.add(change.getNewIndex(), change.getDocument());
notifyItemInserted(change.getNewIndex());
}
protected void onDocumentModified(DocumentChange change){
if (change.getOldIndex() == change.getNewIndex()) {
mSnapshots.set(change.getOldIndex(), change.getDocument());
notifyItemChanged(change.getOldIndex());
} else {
mSnapshots.remove(change.getOldIndex());
mSnapshots.add(change.getNewIndex(), change.getDocument());
notifyItemMoved(change.getOldIndex(), change.getNewIndex());
}
}
protected void onDocumentRemoved(DocumentChange change){
mSnapshots.remove(change.getOldIndex());
notifyItemRemoved(change.getOldIndex());
}
@Override
public int getItemCount() {
return mSnapshots.size();
}
protected DocumentSnapshot getSnapshot(int index) {
return mSnapshots.get(index);
}
protected void onError(FirebaseFirestoreException e) {};
protected void onDataChanged() {}
}