GT2/Ejectable/node_modules/react-native-gesture-handler/ios/RNGestureHandlerButton.m

71 lines
2.4 KiB
Objective-C

//
// RNGestureHandlerButton.m
// RNGestureHandler
//
// Created by Krzysztof Magiera on 12/10/2017.
// Copyright © 2017 Software Mansion. All rights reserved.
//
#import "RNGestureHandlerButton.h"
#import <UIKit/UIKit.h>
/**
* Gesture Handler Button components overrides standard mechanism used by RN
* to determine touch target, which normally would reurn the UIView that is placed
* as the deepest element in the view hierarchy.
* It's done this way as it allows for the actual target determination to run in JS
* where we can travers up the view ierarchy to find first element that want to became
* JS responder.
*
* Since we want to use native button (or actually a `UIControl`) we need to determine
* the target in native. This makes it impossible for JS responder based components to
* function as a subviews of the button component. Here we override `hitTest:withEvent:`
* method and we only determine the target to be either a subclass of `UIControl` or a
* view that has gesture recognizers registered.
*
* This "default" behaviour of target determinator should be sufficient in most of the
* cases as in fact it is not that common UI pattern to have many nested buttons (usually
* there are just two levels e.g. when you have clickable table cells with additional
* buttons). In cases when the default behaviour is insufficient it is recommended to use
* `TapGestureHandler` instead of a button which gives much better flexibility as far as
* controlling the touch flow.
*/
@implementation RNGestureHandlerButton
- (instancetype)init
{
self = [super init];
if (self) {
_hitTestEdgeInsets = UIEdgeInsetsZero;
#if !TARGET_OS_TV
[self setExclusiveTouch:YES];
#endif
}
return self;
}
- (BOOL)shouldHandleTouch:(UIView *)view
{
return [view isKindOfClass:[UIControl class]] || [view.gestureRecognizers count] > 0;
}
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event
{
if (UIEdgeInsetsEqualToEdgeInsets(self.hitTestEdgeInsets, UIEdgeInsetsZero)) {
return [super pointInside:point withEvent:event];
}
CGRect hitFrame = UIEdgeInsetsInsetRect(self.bounds, self.hitTestEdgeInsets);
return CGRectContainsPoint(hitFrame, point);
}
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
UIView *inner = [super hitTest:point withEvent:event];
while (inner && ![self shouldHandleTouch:inner]) inner = inner.superview;
return inner;
}
@end