react-native/Libraries/NativeAnimation/Nodes/RCTDiffClampAnimatedNode.m
Janic Duplessis c47759a9ae Fix potential retain cycles in Animated iOS
Summary:
Fixes potential retain cycles detected by an internal fb tool.

```
First:

__NSDictionaryM
-> RCTPropsAnimatedNode
-> _parentNodes -> __NSDictionaryM
-> RCTStyleAnimatedNode
-> _childNodes -> __NSDictionaryM

Second:

RCTScrollView
-> _eventDispatcher -> RCTEventDispatcher
-> _observers -> __NSArrayM
-> RCTNativeAnimatedModule
-> _nodesManager -> RCTNativeAnimatedNodesManager
-> _uiManager -> RCTUIManager
-> _viewRegistry -> __NSDictionaryM
-> RCTScrollView
```

First fix:
Use weak map for parent and child nodes, strong refs are managed by RCTNativeAnimatedNodesManager

Second fix:
Make RCTEventDispatcher observers a weak array and make sure we don't keep strong refs to UIManager in RCTNativeAnimatedNodesManager and RCTPropsAnimatedNode.

Tested that native animations still work in UIExplorer

[IOS] [BUGFIX] [NativeAnimated] - Fix potential retain cycles in Animated iOS
Closes https://github.com/facebook/react-native/pull/16506

Differential Revision: D6126400

Pulled By: shergin

fbshipit-source-id: 1ac5083f8ab79a806305edc23ae4796ed428f78b
2017-10-23 13:20:59 -07:00

64 lines
1.5 KiB
Objective-C

/**
* Copyright (c) 2015-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.
*/
#import "RCTDiffClampAnimatedNode.h"
#import <React/RCTLog.h>
@implementation RCTDiffClampAnimatedNode
{
NSNumber *_inputNodeTag;
CGFloat _min;
CGFloat _max;
CGFloat _lastValue;
}
- (instancetype)initWithTag:(NSNumber *)tag
config:(NSDictionary<NSString *, id> *)config
{
if (self = [super initWithTag:tag config:config]) {
_inputNodeTag = config[@"input"];
_min = [config[@"min"] floatValue];
_max = [config[@"max"] floatValue];
}
return self;
}
- (void)onAttachedToNode:(RCTAnimatedNode *)parent
{
[super onAttachedToNode:parent];
self.value = _lastValue = [self inputNodeValue];
}
- (void)performUpdate
{
[super performUpdate];
CGFloat value = [self inputNodeValue];
CGFloat diff = value - _lastValue;
_lastValue = value;
self.value = MIN(MAX(self.value + diff, _min), _max);
}
- (CGFloat)inputNodeValue
{
RCTValueAnimatedNode *inputNode = (RCTValueAnimatedNode *)[self.parentNodes objectForKey:_inputNodeTag];
if (![inputNode isKindOfClass:[RCTValueAnimatedNode class]]) {
RCTLogError(@"Illegal node ID set as an input for Animated.DiffClamp node");
return 0;
}
return inputNode.value;
}
@end