Swiftgram/AsyncDisplayKit/Private/ASDataController+Subclasses.h
Huy Nguyen 74c6cca0b6 [ASDataController] Refactor ASDataController (#3017)
* Refactor ASDataController

Check optional methods in ASDataControllerSource

* Reimplement reloadData

* Refactor new code
- No more new/inserted contexts flag
- Encapsulate code shared between reloadData and updateWithChangeSet
- Remove dataControllerWillDeleteAllData delegate method
- Hierarchy changes no longer needs to conform to NSCopying
- Reword TODOs

* Forgot to call completion block of reloadData :P

* Completion block of -[ASDataController reloadDataWithCompletion:] is nullable

* Data queried from ASCollectionNode and ASTableNode should be in UIKit index space
- This helps to avoid immature node allocation, especially when node virtualization is a thing
- However, this means that -reloadDataInitiallyIfNeeded in ASCollectionNode and ASTableNode must wait until all updates are finished.

* ASDataController shouldn't assume that allocated nodes were also laid out

* Revert "Data queried from ASCollectionNode and ASTableNode should be in UIKit index space"

This reverts commit 7bc977b3808a92f484b297781d0f5b30aa258e17.

* -nodeAtIndexPath: of ASDataController now forces node allocation, with the assumption that clients absolutely need it.
- Revisit this when node virtualization is implemented.

* ASDataController only grab changeSet.completionHandler when needed because it'll be niled out

* Fix ASTableViewTests related to reloadData

* Fix testThatDeletedItemsAreMarkedInvisible in ASCollectionViewTests

* Minor changes in ASCollectionView and ASTableView

* ASCollectionView and ASTableView shouldn't call [super reloadData] before their data controller does anything

* Address comments

* Fuse reloadData into -updateWithChangeSet: of ASDataController

* reloadData shouldn't be called as if it's inside a batch
- It can't be used in conjuntion with other updates.
- Calling it inside a batch update during the initial load can cause data inconsistency thrown by UICollectionView/UITableView

* Refactor ASDataControllerDelegate and ASRangeControllerDelegate
- Replace delegate methods in these protocols with -willUpdateWithChangeSet and -didUpdateWithChangeSet.
- ASRangeController, ASCollectionView and ASTableView are simplified because of this.

* Fix mismatch between sorting orders in ASDataController

* Forgot to call completion handler of reload change sets

* Make sure ASCollectionView is compatible with the behavior of UICollectionView's reloadData
- Since UICollectionView's reloadData doesn't requery data source but defers until the next layout pass,  we need to wait until then to update range controller and do batch fetching.
- `-[ASCollectionView waitUntilAllUpdatesAreCommited]` needs to force a layout pass to make sure
everything is ready after it returns.

* testSectionIndexHandling of ASTableViewTests should only check visible nodes. Other nodes will be re-measured later.

* ASTableView is not ready until the first layout pass finished

* Address comments

* Bug fixes
2017-02-22 13:50:07 -08:00

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7.6 KiB
Objective-C

//
// ASDataController+Subclasses.h
// AsyncDisplayKit
//
// Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
#ifndef MINIMAL_ASDK
#pragma once
#import <vector>
@class ASIndexedNodeContext;
typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCellNode *> *nodes, NSArray<NSIndexPath *> *indexPaths);
@interface ASDataController (Subclasses)
#pragma mark - Internal editing & completed store querying
/**
* Read-only access to the underlying editing nodes of the given kind
*/
- (NSMutableArray *)editingNodesOfKind:(NSString *)kind;
/**
* Read only access to the underlying completed nodes of the given kind
*/
- (NSMutableArray *)completedNodesOfKind:(NSString *)kind;
#pragma mark - Node sizing
/**
* Measure and layout the given nodes in optimized batches, constraining each to a given size in `constrainedSizeForNodeOfKind:atIndexPath:`.
*
* This method runs synchronously.
* @param batchCompletion A handler to be run after each batch is completed. It is executed synchronously on the calling thread.
*/
- (void)batchLayoutNodesFromContexts:(NSArray<ASIndexedNodeContext *> *)contexts batchCompletion:(ASDataControllerCompletionBlock)batchCompletionHandler;
/**
* Provides the size range for a specific node during the layout process.
*/
- (ASSizeRange)constrainedSizeForNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
#pragma mark - Node & Section Insertion/Deletion API
/**
* Inserts the given nodes of the specified kind into the backing store, calling completion on the main thread when the write finishes.
*/
- (void)insertNodes:(NSArray *)nodes ofKind:(NSString *)kind atIndexPaths:(NSArray *)indexPaths completion:(ASDataControllerCompletionBlock)completionBlock;
/**
* Deletes the given nodes of the specified kind in the backing store, calling completion on the main thread when the deletion finishes.
*/
- (void)deleteNodesOfKind:(NSString *)kind atIndexPaths:(NSArray *)indexPaths completion:(ASDataControllerCompletionBlock)completionBlock;
/**
* Inserts the given sections of the specified kind in the backing store, calling completion on the main thread when finished.
*/
- (void)insertSections:(NSMutableArray *)sections ofKind:(NSString *)kind atIndexSet:(NSIndexSet *)indexSet completion:(void (^)(NSArray *sections, NSIndexSet *indexSet))completionBlock;
/**
* Deletes the given sections in the backing store, calling completion on the main thread when finished.
*/
- (void)deleteSections:(NSIndexSet *)indexSet completion:(void (^)())completionBlock;
#pragma mark - Data Manipulation Hooks
/**
* Notifies the subclass to perform any work needed before the data controller is reloaded entirely
*
* @discussion This method will be performed before the data controller enters its editing queue.
* The data source is locked at this point and accessing it is safe. Use this method to set up any nodes or
* data stores before entering into editing the backing store on a background thread.
*/
- (void)prepareForReloadDataWithSectionCount:(NSInteger)newSectionCount;
/**
* Notifies the subclass that the data controller is about to reload its data entirely
*
* @discussion This method will be performed on the data controller's editing background queue before the parent's
* concrete implementation. This is a great place to perform new node creation like supplementary views
* or header/footer nodes.
*/
- (void)willReloadDataWithSectionCount:(NSInteger)newSectionCount;
/**
* Notifies the subclass to perform setup before sections are inserted in the data controller
*
* @discussion This method will be performed before the data controller enters its editing queue.
* The data source is locked at this point and accessing it is safe. Use this method to set up any nodes or
* data stores before entering into editing the backing store on a background thread.
*
* @param sections Indices of sections to be inserted
*/
- (void)prepareForInsertSections:(NSIndexSet *)sections;
/**
* Notifies the subclass that the data controller will insert new sections at the given position
*
* @discussion This method will be performed on the data controller's editing background queue before the parent's
* concrete implementation. This is a great place to perform any additional transformations like supplementary views
* or header/footer nodes.
*
* @param sections Indices of sections to be inserted
*/
- (void)willInsertSections:(NSIndexSet *)sections;
/**
* Notifies the subclass to perform setup before sections are deleted in the data controller
*
* @discussion This method will be performed before the data controller enters its editing queue.
* The data source is locked at this point and accessing it is safe. Use this method to set up any nodes or
* data stores before entering into editing the backing store on a background thread.
*
* @param sections Indices of sections to be inserted
*/
- (void)prepareForDeleteSections:(NSIndexSet *)sections;
/**
* Notifies the subclass that the data controller will delete sections at the given positions
*
* @discussion This method will be performed on the data controller's editing background queue before the parent's
* concrete implementation. This is a great place to perform any additional transformations like supplementary views
* or header/footer nodes.
*
* @param sections Indices of sections to be deleted
*/
- (void)willDeleteSections:(NSIndexSet *)sections;
/**
* Notifies the subclass to perform setup before rows are inserted in the data controller.
*
* @discussion This method will be performed before the data controller enters its editing queue.
* The data source is locked at this point and accessing it is safe. Use this method to set up any nodes or
* data stores before entering into editing the backing store on a background thread.
*
* @param indexPaths Index paths for the rows to be inserted.
*/
- (void)prepareForInsertRowsAtIndexPaths:(NSArray<NSIndexPath *> *)indexPaths;
/**
* Notifies the subclass that the data controller will insert new rows at the given index paths.
*
* @discussion This method will be performed on the data controller's editing background queue before the parent's
* concrete implementation. This is a great place to perform any additional transformations like supplementary views
* or header/footer nodes.
*
* @param indexPaths Index paths for the rows to be inserted.
*/
- (void)willInsertRowsAtIndexPaths:(NSArray<NSIndexPath *> *)indexPaths;
/**
* Notifies the subclass to perform setup before rows are deleted in the data controller.
*
* @discussion This method will be performed before the data controller enters its editing queue.
* The data source is locked at this point and accessing it is safe. Use this method to set up any nodes or
* data stores before entering into editing the backing store on a background thread.
*
* @param indexPaths Index paths for the rows to be deleted.
*/
- (void)prepareForDeleteRowsAtIndexPaths:(NSArray<NSIndexPath *> *)indexPaths;
/**
* Notifies the subclass that the data controller will delete rows at the given index paths.
*
* @discussion This method will be performed before the data controller enters its editing queue.
* The data source is locked at this point and accessing it is safe. Use this method to set up any nodes or
* data stores before entering into editing the backing store on a background thread.
*
* @param indexPaths Index paths for the rows to be deleted.
*/
- (void)willDeleteRowsAtIndexPaths:(NSArray<NSIndexPath *> *)indexPaths;
@end
#endif