alpha7 update

Change-Id: I5da44eeb96a9acf4adf76e0ade70b9ae43a4308e

Author: samtstern

constants.gradle

@@ -11,6 +11,6 @@ project.ext {
     firebaseVersion = '11.8.0'
     firebaseVersion = '12.0.1'
     supportLibraryVersion = '27.1.0'
-    architectureVersion = '1.1.0'
+    architectureVersion = '1.1.1'
     kotlinVersion = '1.2.30'
 }

firestore/build.gradle

@@ -23,8 +23,8 @@ dependencies {
     annotationProcessor "android.arch.lifecycle:compiler:$architectureVersion"
 
 
-    api "android.arch.paging:common:1.0.0-alpha6"
-    api "android.arch.paging:runtime:1.0.0-alpha6"
+    api "android.arch.paging:common:1.0.0-alpha7"
+    api "android.arch.paging:runtime:1.0.0-alpha7"
 
     androidTestImplementation 'junit:junit:4.12'
     androidTestImplementation 'com.android.support.test:runner:1.0.1'

firestore/src/main/java/com/firebase/ui/firestore/paging/FirestoreDataSource.java

@@ -3,6 +3,8 @@
 import android.arch.paging.DataSource;
 import android.arch.paging.PageKeyedDataSource;
 import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.support.annotation.RestrictTo;
 import android.util.Log;
 
 import com.google.android.gms.tasks.OnFailureListener;
@@ -11,12 +13,13 @@
 import com.google.firebase.firestore.Query;
 import com.google.firebase.firestore.QuerySnapshot;
 
+import java.util.Collections;
 import java.util.List;
 
 /**
- * Created by samstern on 3/15/18.
+ * Data source to power a {@link FirestorePagingAdapter}.
  */
-
+@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
 public class FirestoreDataSource extends PageKeyedDataSource<PageKey, DocumentSnapshot> {
 
     private static final String TAG = "FirestoreDataSource";
@@ -57,7 +60,13 @@ public void onSuccess(QuerySnapshot snapshots) {
                 .addOnFailureListener(new OnFailureListener() {
                     @Override
                     public void onFailure(@NonNull Exception e) {
-                        // TODO: errors?
+                        Log.w(TAG, "loadInitial:failure", e);
+
+                        // On error, return an empty page with the next page key being basically
+                        // equal to the initial query.
+                        PageKey nextPage = new PageKey(null, null);
+                        callback.onResult(Collections.<DocumentSnapshot>emptyList(),
+                                null, nextPage);
                     }
                 });
 
@@ -74,7 +83,7 @@ public void loadBefore(@NonNull LoadParams<PageKey> params,
     @Override
     public void loadAfter(@NonNull LoadParams<PageKey> params,
                           @NonNull final LoadCallback<PageKey, DocumentSnapshot> callback) {
-        PageKey key = params.key;
+        final PageKey key = params.key;
         Log.d(TAG, "loadAfter: " + key + ", " + params.requestedLoadSize);
 
         key.getPageQuery(mBaseQuery, params.requestedLoadSize)
@@ -92,17 +101,22 @@ public void onSuccess(QuerySnapshot snapshots) {
                 .addOnFailureListener(new OnFailureListener() {
                     @Override
                     public void onFailure(@NonNull Exception e) {
+                        Log.w(TAG, "loadAfter:failure", e);
 
+                        // On error, return an empty page with the next page key being basically
+                        // equal to the initial query.
+                        callback.onResult(Collections.<DocumentSnapshot>emptyList(), key);
                     }
                 });
 
     }
 
+    @Nullable
     private DocumentSnapshot getLast(List<DocumentSnapshot> data) {
-        DocumentSnapshot last = (data == null || data.isEmpty())
-                ? null
-                : data.get(data.size() - 1);
-
-        return last;
+        if (data == null || data.isEmpty()) {
+            return null;
+        } else {
+            return data.get(data.size() - 1);
+        }
     }
 }

firestore/src/main/java/com/firebase/ui/firestore/paging/FirestorePagingAdapter.java

@@ -1,7 +1,10 @@
 package com.firebase.ui.firestore.paging;
 
+import android.arch.lifecycle.Lifecycle;
+import android.arch.lifecycle.LifecycleObserver;
 import android.arch.lifecycle.LiveData;
 import android.arch.lifecycle.Observer;
+import android.arch.lifecycle.OnLifecycleEvent;
 import android.arch.paging.PagedList;
 import android.arch.paging.PagedListAdapter;
 import android.support.annotation.NonNull;
@@ -14,10 +17,13 @@
 import com.google.firebase.firestore.DocumentSnapshot;
 
 /**
- * TODO(samstern): Document
+ * Paginated RecyclerView Adapter for a Cloud Firestore query.
+ *
+ * Configured with {@link FirestorePagingOptions}.
  */
 public abstract class FirestorePagingAdapter<T, VH extends RecyclerView.ViewHolder>
-        extends PagedListAdapter<DocumentSnapshot, VH> {
+        extends PagedListAdapter<DocumentSnapshot, VH>
+        implements LifecycleObserver {
 
     private final SnapshotParser<T> mParser;
     private final LiveData<PagedList<DocumentSnapshot>> mData;
@@ -62,14 +68,17 @@ public FirestorePagingAdapter(@NonNull FirestorePagingOptions<T> options) {
         mParser = options.getParser();
         mData = options.getData();
 
-        // TODO: Lifecycle owner
+        if (options.getOwner() != null) {
+            options.getOwner().getLifecycle().addObserver(this);
+        }
     }
 
-    // TODO: Unify method names with other adapters
+    @OnLifecycleEvent(Lifecycle.Event.ON_START)
     public void startListening() {
         mData.observeForever(mObserver);
     }
 
+    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
     public void stopListening() {
         mData.removeObserver(mObserver);
     }
@@ -84,7 +93,6 @@ public void onBindViewHolder(@NonNull VH holder, int position) {
         onBindViewHolder(holder, position, mParser.parseSnapshot(snapshot));
     }
 
-    // TODO: Check that this is the right visibility
     protected abstract void onBindViewHolder(@NonNull VH holder, int position, T model);
 
     private void onListChanged(@NonNull PagedList<DocumentSnapshot> snapshots) {

firestore/src/main/java/com/firebase/ui/firestore/paging/FirestorePagingOptions.java

@@ -13,12 +13,10 @@
 import com.google.firebase.firestore.Query;
 
 /**
- * TODO: Document
+ * Options to conifigure an {@link FirestorePagingAdapter}.
  */
 public class FirestorePagingOptions<T> {
 
-    // TODO: Default config
-
     private final LiveData<PagedList<DocumentSnapshot>> mData;
     private final SnapshotParser<T> mParser;
     private final LifecycleOwner mOwner;

firestore/src/main/java/com/firebase/ui/firestore/paging/PageKey.java

@@ -1,13 +1,15 @@
 package com.firebase.ui.firestore.paging;
 
 import android.support.annotation.Nullable;
+import android.support.annotation.RestrictTo;
 
 import com.google.firebase.firestore.DocumentSnapshot;
 import com.google.firebase.firestore.Query;
 
 /**
- * TODO: Document.
+ * Key for Firestore pagination. Holds the DocumentSnapshot(s) that bound the page.
  */
+@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
 public class PageKey {
 
     private final DocumentSnapshot mStartAfter;