react-native/Libraries/NativeAnimation/Nodes/RCTDiffClampAnimatedNode.m

62 lines
1.3 KiB
Objective-C

/**
* Copyright (c) 2015-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
#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