refactor(ios): remove unused data structure in waterfall item

renderer/native/ios/renderer/component/waterfalllist/HippyShadowListView.h

@@ -25,30 +25,12 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-@interface WaterfallItemChangeContext : NSObject<NSCopying>
-
-- (NSHashTable<__kindof HippyShadowView *> *)addedItems;
-- (NSHashTable<__kindof HippyShadowView *> *)frameChangedItems;
-- (NSSet<__kindof HippyShadowView *> *)deletedItems;
-- (NSHashTable<__kindof HippyShadowView *> *)movedItems;
-
-/// Clear all items recorded.
-- (void)clear;
-
-/// Whether has changed item.
-- (BOOL)hasChanges;
-
-/// Get all chaned items.
-- (NSSet<HippyShadowView *> *)allChangedItems;
-
-@end
-
+/// ListView's shadowView
 @interface HippyShadowListView : HippyShadowView <HippyShadowWaterfallItemFrameChangedProtocol>
 
-///// Whether current ShadowList is dirty.
-//@property (nonatomic, assign) BOOL isDirty;
-
-@property(nonatomic, readonly, strong)WaterfallItemChangeContext *itemChangeContext;
+/// Whether current ShadowList is dirty.
+/// Used to determine whether the list needs reload.
+@property (nonatomic, assign) BOOL isDirty;
 
 @end
 

renderer/native/ios/renderer/component/waterfalllist/HippyShadowListView.m

@@ -0,0 +1,52 @@
+/*!
+ * iOS SDK
+ *
+ * Tencent is pleased to support the open source community by making
+ * Hippy available.
+ *
+ * Copyright (C) 2019 THL A29 Limited, a Tencent company.
+ * 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.
+ */
+
+#import "HippyShadowListView.h"
+#import "HippyWaterfallView.h"
+#import "HippyAssert.h"
+
+
+@implementation HippyShadowListView
+
+- (void)insertHippySubview:(HippyShadowView *)subview atIndex:(NSUInteger)atIndex {
+    [super insertHippySubview:subview atIndex:atIndex];
+    if ([subview isKindOfClass:[HippyShadowWaterfallItem class]]) {
+        HippyShadowWaterfallItem *objectItem = (HippyShadowWaterfallItem *)subview;
+        objectItem.observer = self;
+    }
+    self.isDirty = YES;
+}
+
+- (void)removeHippySubview:(HippyShadowView *)subview {
+    [super removeHippySubview:subview];
+    if ([subview isKindOfClass:[HippyShadowWaterfallItem class]]) {
+        HippyShadowWaterfallItem *objectItem = (HippyShadowWaterfallItem *)subview;
+        objectItem.observer = nil;
+    }
+    self.isDirty = YES;
+}
+
+- (void)itemFrameChanged:(__kindof HippyShadowWaterfallItem *)item {
+    self.isDirty = YES;
+}
+
+@end

renderer/native/ios/renderer/component/waterfalllist/HippyShadowWaterfallItem.h

@@ -29,14 +29,19 @@ NS_ASSUME_NONNULL_BEGIN
 @protocol HippyShadowWaterfallItemFrameChangedProtocol <NSObject>
 
 @required
+/// Calledn when item frame changed
+/// - Parameter item: shadow waterfall item
 - (void)itemFrameChanged:(__kindof HippyShadowWaterfallItem *)item;
 
 @end
 
+/// Waterfall item's shadowView
 @interface HippyShadowWaterfallItem : HippyShadowView
 
-@property(nonatomic, assign, getter=isLayoutDirty) BOOL layoutDirty;
-@property(nonatomic, weak) id<HippyShadowWaterfallItemFrameChangedProtocol> observer;
+@property (nonatomic, assign, getter=isLayoutDirty) BOOL layoutDirty;
+
+/// frame change observer, usually is shadowListView
+@property (nonatomic, weak) id<HippyShadowWaterfallItemFrameChangedProtocol> observer;
 
 @end
 

renderer/native/ios/renderer/component/waterfalllist/HippyWaterfallView.mm

@@ -198,11 +198,11 @@ - (BOOL)isManualScrolling {
 
 - (void)hippyBridgeDidFinishTransaction {
     HippyShadowListView *listNode = self.hippyShadowView;
-    if (!_dataSource || (listNode && listNode.itemChangeContext.hasChanges)) {
-        HippyLogTrace(@"🔥 %@ Reload %@", self.hippyTag, [[listNode itemChangeContext] description]);
+    if (!_dataSource || (listNode && listNode.isDirty)) {
+        HippyLogTrace(@"🔥 %@ Reload", self.hippyTag);
         [self cacheVisibleCellViewsForReuse];
         [self reloadData];
-        [listNode.itemChangeContext clear];
+        listNode.isDirty = NO;
     }
 }