Update FirebaseUI database's indexed data sources

morganchen12 · morganchen12 · commit 6b2b5b57c788 · 2018-05-08T11:05:03.000-07:00
Change-Id: I32f9409a69dafbde5587505e503c2735dbe8f689
diff --git a/FirebaseAuthUITests/FUIAuthTest.m b/FirebaseAuthUITests/FUIAuthTest.m
@@ -15,7 +15,6 @@
 //
 
 @import XCTest;
-@import FirebaseAnalytics;
 @import FirebaseAuth;
 @import FirebaseAuthUI;
 #import <OCMock/OCMock.h>
diff --git a/FirebaseDatabaseUI/FUIIndexArray.h b/FirebaseDatabaseUI/FUIIndexArray.h
@@ -170,9 +170,15 @@ didFailLoadWithError:(NSError *)error;
  */
 - (nullable FIRDataSnapshot *)objectAtIndex:(NSUInteger)index;
 
+/**
+ * Starts observing the index array's listeners. The indexed array will pass updates to its delegate
+ * until the `invalidate` method is called.
+ */
+- (void)observeQuery;
+
 /**
  * Removes all observers from all queries managed by this array and renders this array
- * unusable.
+ * unusable. Initialize a new array instead of reusing this array.
  */
 - (void)invalidate;
 
diff --git a/FirebaseDatabaseUI/FUIIndexArray.m b/FirebaseDatabaseUI/FUIIndexArray.m
@@ -59,7 +59,6 @@ - (instancetype)initWithIndex:(id<FUIDataObservable>)index
     _data = data;
     _observers = [NSMutableArray array];
     _delegate = delegate;
-    [self observeQueries];
   }
   return self;
 }
@@ -93,6 +92,10 @@ - (NSUInteger)count {
   return self.observers.count;
 }
 
+- (void)observeQuery {
+  [self observeQueries];
+}
+
 // FUIIndexArray instance becomes unusable after invalidation.
 - (void)invalidate {
   for (NSInteger i = 0; i < self.observers.count; i++) {
diff --git a/FirebaseDatabaseUI/FUIIndexCollectionViewDataSource.h b/FirebaseDatabaseUI/FUIIndexCollectionViewDataSource.h
@@ -19,7 +19,7 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-@class FUIIndexCollectionViewDataSource;
+@class FUIIndexCollectionViewDataSource, FUIIndexArray;
 
 @protocol FUIIndexCollectionViewDataSourceDelegate <NSObject>
 @optional
@@ -70,6 +70,22 @@ didFailLoadAtIndex:(NSUInteger)index
 
 - (instancetype)init NS_UNAVAILABLE;
 
+/**
+ * Initializes a collection view data source.
+ * @param indexArray The FUIIndexArray whose contents will be displayed in the collection view.
+ * @param collectionView The collection view that is populated by this data source. The
+ *   data source pulls updates from Firebase database, so it must maintain a reference
+ *   to the collection view in order to update its contents as the database pushes updates.
+ *   The collection view is not retained by its data source.
+ * @param populateCell The closure invoked when populating a UICollectionViewCell (or subclass).
+ */
+- (instancetype)initWithIndexArray:(FUIIndexArray *)indexArray
+                          delegate:(nullable id<FUIIndexCollectionViewDataSourceDelegate>)delegate
+                      populateCell:(UICollectionViewCell *(^)(UICollectionView *collectionView,
+                                                              NSIndexPath *indexPath,
+                                                              FIRDataSnapshot *_Nullable snap))populateCell
+                                                                  NS_DESIGNATED_INITIALIZER;
+
 /**
  * Initializes a collection view data source.
  * @param indexQuery The Firebase query containing children of the data query.
@@ -84,11 +100,10 @@ didFailLoadAtIndex:(NSUInteger)index
  */
 - (instancetype)initWithIndex:(FIRDatabaseQuery *)indexQuery
                          data:(FIRDatabaseReference *)dataQuery
-               collectionView:(UICollectionView *)collectionView
                      delegate:(nullable id<FUIIndexCollectionViewDataSourceDelegate>)delegate
                  populateCell:(UICollectionViewCell *(^)(UICollectionView *collectionView,
                                                          NSIndexPath *indexPath,
-                                                         FIRDataSnapshot *_Nullable snap))populateCell NS_DESIGNATED_INITIALIZER;
+                                                         FIRDataSnapshot *_Nullable snap))populateCell;
 
 /**
  * Returns the snapshot at the given index, if it has loaded.
@@ -98,6 +113,18 @@ didFailLoadAtIndex:(NSUInteger)index
  */
 - (nullable FIRDataSnapshot *)snapshotAtIndex:(NSInteger)index;
 
+/**
+ * Attaches the data source to a collection view and begins sending updates immediately.
+ * @param view An instance of UICollectionView that the data source should push
+ *   updates to.
+ */
+- (void)bindToView:(UICollectionView *)view;
+
+/**
+ * Detaches the data source from a view and stops sending any updates.
+ */
+- (void)unbind;
+
 @end
 
 @interface UICollectionView (FUIIndexCollectionViewDataSource)
diff --git a/FirebaseDatabaseUI/FUIIndexCollectionViewDataSource.m b/FirebaseDatabaseUI/FUIIndexCollectionViewDataSource.m
@@ -21,7 +21,7 @@
 @interface FUIIndexCollectionViewDataSource () <FUIIndexArrayDelegate>
 
 @property (nonatomic, readonly, nonnull) FUIIndexArray *array;
-@property (nonatomic, readonly, weak) UICollectionView *collectionView;
+@property (nonatomic, weak, nullable) UICollectionView *collectionView;
 
 @property (nonatomic, readonly, copy) UICollectionViewCell *(^populateCell)
   (UICollectionView *collectionView, NSIndexPath *indexPath, FIRDataSnapshot *object);
@@ -32,17 +32,24 @@ @implementation FUIIndexCollectionViewDataSource
 
 - (instancetype)initWithIndex:(FIRDatabaseQuery *)indexQuery
                          data:(FIRDatabaseReference *)dataQuery
-               collectionView:(UICollectionView *)collectionView
+                     delegate:(id<FUIIndexCollectionViewDataSourceDelegate>)delegate
+                 populateCell:(UICollectionViewCell *(^)(UICollectionView *collectionView,
+                                                         NSIndexPath *indexPath,
+                                                         FIRDataSnapshot *snap))populateCell {
+  FUIIndexArray *array = [[FUIIndexArray alloc] initWithIndex:indexQuery
+                                                         data:dataQuery
+                                                     delegate:self];
+  return [self initWithIndexArray:array delegate:delegate populateCell:populateCell];
+}
+
+- (instancetype)initWithIndexArray:(FUIIndexArray *)indexArray
                      delegate:(id<FUIIndexCollectionViewDataSourceDelegate>)delegate
                  populateCell:(UICollectionViewCell *(^)(UICollectionView *collectionView,
                                                          NSIndexPath *indexPath,
                                                          FIRDataSnapshot *snap))populateCell {
   self = [super init];
   if (self != nil) {
-    _array = [[FUIIndexArray alloc] initWithIndex:indexQuery
-                                                  data:dataQuery
-                                              delegate:self];
-    _collectionView = collectionView;
+    _array = indexArray;
     _collectionView.dataSource = self;
     _populateCell = populateCell;
     _delegate = delegate;
@@ -58,6 +65,18 @@ - (FIRDataSnapshot *)snapshotAtIndex:(NSInteger)index {
   return [self.array objectAtIndex:index];
 }
 
+- (void)bindToView:(UICollectionView *)view {
+  self.collectionView = view;
+  view.dataSource = self;
+  [self.array observeQuery];
+}
+
+- (void)unbind {
+  [self.array invalidate];
+  self.collectionView.dataSource = nil;
+  self.collectionView = nil;
+}
+
 #pragma mark - FUIIndexArrayDelegate
 
 - (void)array:(FUIIndexArray *)array
@@ -115,7 +134,8 @@ - (void)array:(FUIIndexArray *)array
 
 #pragma mark - UICollectionViewDataSource
 
-- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
+- (NSInteger)collectionView:(UICollectionView *)collectionView
+     numberOfItemsInSection:(NSInteger)section {
   return self.array.count;
 }
 
@@ -131,18 +151,17 @@ - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView
 @implementation UICollectionView (FUIIndexCollectionViewDataSource)
 
 - (FUIIndexCollectionViewDataSource *)bindToIndexedQuery:(FIRDatabaseQuery *)index
-                                                    data:(FIRDatabaseReference *)data
-                                                delegate:(id<FUIIndexCollectionViewDataSourceDelegate>)delegate
-                                            populateCell:(UICollectionViewCell *(^)(UICollectionView *,
-                                                                                    NSIndexPath *,
-                                                                                    FIRDataSnapshot *))populateCell {
+    data:(FIRDatabaseReference *)data
+    delegate:(id<FUIIndexCollectionViewDataSourceDelegate>)delegate
+    populateCell:(UICollectionViewCell *(^)(UICollectionView *,
+                                            NSIndexPath *,
+                                            FIRDataSnapshot *))populateCell {
   FUIIndexCollectionViewDataSource *dataSource =
     [[FUIIndexCollectionViewDataSource alloc] initWithIndex:index
-                                                            data:data
-                                                  collectionView:self
-                                                        delegate:delegate
-                                                    populateCell:populateCell];
-  self.dataSource = dataSource;
+                                                       data:data
+                                                   delegate:delegate
+                                               populateCell:populateCell];
+  [dataSource bindToView:self];
   return dataSource;
 }
 
diff --git a/FirebaseDatabaseUI/FUIIndexTableViewDataSource.h b/FirebaseDatabaseUI/FUIIndexTableViewDataSource.h
@@ -19,7 +19,7 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-@class FUIIndexTableViewDataSource;
+@class FUIIndexTableViewDataSource, FUIIndexArray;
 
 @protocol FUIIndexTableViewDataSourceDelegate <NSObject>
 @optional
@@ -74,7 +74,7 @@ didFailLoadAtIndex:(NSUInteger)index
  * Initializes a table view data source.
  * @param indexQuery The Firebase query containing children of the data query.
  * @param dataQuery The reference whose children correspond to the contents of the
- *   index query. This reference's children's contents are served as teh contents 
+ *   index query. This reference's children's contents are served as the contents
  *   of the table view that adopts this data source.
  * @param tableView The table view that is populated by this data source. The
  *   data source pulls updates from Firebase database, so it must maintain a reference
@@ -84,11 +84,26 @@ didFailLoadAtIndex:(NSUInteger)index
  */
 - (instancetype)initWithIndex:(FIRDatabaseQuery *)indexQuery
                          data:(FIRDatabaseReference *)dataQuery
-                    tableView:(UITableView *)tableView
                      delegate:(nullable id<FUIIndexTableViewDataSourceDelegate>)delegate
                  populateCell:(UITableViewCell *(^)(UITableView *tableView,
                                                     NSIndexPath *indexPath,
-                                                    FIRDataSnapshot *_Nullable snap))populateCell NS_DESIGNATED_INITIALIZER;
+                                                    FIRDataSnapshot *_Nullable snap))populateCell;
+
+/**
+ * Initializes a table view data source.
+ * @param indexArray The FUIIndexArray whose contents will be displayed in the table view.
+ * @param tableView The table view that is populated by this data source. The
+ *   data source pulls updates from Firebase database, so it must maintain a reference
+ *   to the table view in order to update its contents as the database pushes updates.
+ *   The table view is not retained by its data source.
+ * @param populateCell The closure invoked when populating a UITableViewCell (or subclass).
+ */
+- (instancetype)initWithIndexArray:(FUIIndexArray *)indexArray
+                          delegate:(nullable id<FUIIndexTableViewDataSourceDelegate>)delegate
+                      populateCell:(UITableViewCell *(^)(UITableView *tableView,
+                                                         NSIndexPath *indexPath,
+                                                         FIRDataSnapshot *_Nullable snap))populateCell
+                                                             NS_DESIGNATED_INITIALIZER;
 
 /**
  * Returns the snapshot at the given index, if it has loaded.
@@ -98,6 +113,18 @@ didFailLoadAtIndex:(NSUInteger)index
  */
 - (nullable FIRDataSnapshot *)snapshotAtIndex:(NSInteger)index;
 
+/**
+ * Attaches the data source to a table view and begins sending updates immediately.
+ * @param view An instance of UITableView that the data source should push
+ *   updates to.
+ */
+- (void)bindToView:(UITableView *)view;
+
+/**
+ * Detaches the data source from a view and stops sending any updates.
+ */
+- (void)unbind;
+
 @end
 
 @interface UITableView (FUIIndexTableViewDataSource)
diff --git a/FirebaseDatabaseUI/FUIIndexTableViewDataSource.m b/FirebaseDatabaseUI/FUIIndexTableViewDataSource.m
@@ -21,7 +21,7 @@
 @interface FUIIndexTableViewDataSource () <FUIIndexArrayDelegate>
 
 @property (nonatomic, readonly, nonnull) FUIIndexArray *array;
-@property (nonatomic, readonly, weak) UITableView *tableView;
+@property (nonatomic, weak, nullable) UITableView *tableView;
 
 @property (nonatomic, readonly, copy) UITableViewCell *(^populateCell)
   (UITableView *tableView, NSIndexPath *indexPath, FIRDataSnapshot *snap);
@@ -38,26 +38,32 @@ - (instancetype)init {
   @throw e;
 }
 
-- (instancetype)initWithIndex:(FIRDatabaseQuery *)indexQuery
-                         data:(FIRDatabaseReference *)dataQuery
-                    tableView:(UITableView *)tableView
-                     delegate:(nullable id<FUIIndexTableViewDataSourceDelegate>)delegate
-                 populateCell:(UITableViewCell *(^)(UITableView *tableView,
-                                                    NSIndexPath *indexPath,
-                                                    FIRDataSnapshot *snap))populateCell {
+- (instancetype)initWithIndexArray:(FUIIndexArray *)indexArray
+                          delegate:(nullable id<FUIIndexTableViewDataSourceDelegate>)delegate
+                      populateCell:(UITableViewCell *(^)(UITableView *tableView,
+                                                         NSIndexPath *indexPath,
+                                                         FIRDataSnapshot *snap))populateCell {
   self = [super init];
   if (self != nil) {
-    _array = [[FUIIndexArray alloc] initWithIndex:indexQuery
-                                             data:dataQuery
-                                         delegate:self];
-    _tableView = tableView;
-    tableView.dataSource = self;
+    _array = indexArray;
     _populateCell = populateCell;
     _delegate = delegate;
   }
   return self;
 }
 
+- (instancetype)initWithIndex:(FIRDatabaseQuery *)indexQuery
+                         data:(FIRDatabaseReference *)dataQuery
+                     delegate:(nullable id<FUIIndexTableViewDataSourceDelegate>)delegate
+                 populateCell:(UITableViewCell *(^)(UITableView *tableView,
+                                                    NSIndexPath *indexPath,
+                                                    FIRDataSnapshot *snap))populateCell {
+  FUIIndexArray *array = [[FUIIndexArray alloc] initWithIndex:indexQuery
+                                                         data:dataQuery
+                                                     delegate:self];
+  return [self initWithIndexArray:array delegate:delegate populateCell:populateCell];
+}
+
 - (NSArray<FIRDataSnapshot *> *)indexes {
   return self.array.indexes;
 }
@@ -66,6 +72,18 @@ - (FIRDataSnapshot *)snapshotAtIndex:(NSInteger)index {
   return [self.array objectAtIndex:index];
 }
 
+- (void)bindToView:(UITableView *)view {
+  self.tableView = view;
+  view.dataSource = self;
+  [self.array observeQuery];
+}
+
+- (void)unbind {
+  [self.array invalidate];
+  self.tableView.dataSource = nil;
+  self.tableView = nil;
+}
+
 #pragma mark - FUIIndexArrayDelegate 
 
 - (void)array:(FUIIndexArray *)array
@@ -155,10 +173,9 @@ - (FUIIndexTableViewDataSource *)bindToIndexedQuery:(FIRDatabaseQuery *)index
   FUIIndexTableViewDataSource *dataSource =
     [[FUIIndexTableViewDataSource alloc] initWithIndex:index
                                                   data:data
-                                             tableView:self
                                               delegate:delegate
                                           populateCell:populateCell];
-  self.dataSource = dataSource;
+  [dataSource bindToView:self];
   return dataSource;
 }
 
diff --git a/FirebaseDatabaseUITests/FUIIndexArrayTest.m b/FirebaseDatabaseUITests/FUIIndexArrayTest.m
@@ -64,6 +64,7 @@ - (void)setUp {
   self.arrayDelegate = [[FUIIndexArrayTestDelegate alloc] init];
   self.array.delegate = self.arrayDelegate;
   self.dict = [database() mutableCopy];
+  [self.array observeQuery];
 }
 
 - (void)tearDown {
diff --git a/FirebaseUI.xcodeproj/project.pbxproj b/FirebaseUI.xcodeproj/project.pbxproj
diff --git a/Podfile b/Podfile

Original file line number	Diff line number	Diff line change
`@@ -59,7 +59,6 @@ - (instancetype)initWithIndex:(id<FUIDataObservable>)index`
`59`	`59`	`_data = data;`
`60`	`60`	`_observers = [NSMutableArray array];`
`61`	`61`	`_delegate = delegate;`
`62`		`- [self observeQueries];`
`63`	`62`	`}`
`64`	`63`	`return self;`
`65`	`64`	`}`
`@@ -93,6 +92,10 @@ - (NSUInteger)count {`
`93`	`92`	`return self.observers.count;`
`94`	`93`	`}`
`95`	`94`
	`95`	`+- (void)observeQuery {`
	`96`	`+ [self observeQueries];`
	`97`	`+}`
	`98`	`+`
`96`	`99`	`// FUIIndexArray instance becomes unusable after invalidation.`
`97`	`100`	`- (void)invalidate {`
`98`	`101`	`for (NSInteger i = 0; i < self.observers.count; i++) {`
Original file line number	Diff line number	Diff line change
`@@ -64,6 +64,7 @@ - (void)setUp {`
`64`	`64`	`self.arrayDelegate = [[FUIIndexArrayTestDelegate alloc] init];`
`65`	`65`	`self.array.delegate = self.arrayDelegate;`
`66`	`66`	`self.dict = [database() mutableCopy];`
	`67`	`+ [self.array observeQuery];`
`67`	`68`	`}`
`68`	`69`
`69`	`70`	`- (void)tearDown {`