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React Native adopt to xcode 8
/**
* 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 "RCTScrollView.h"
#import <UIKit/UIKit.h>
#import "RCTConvert.h"
#import "RCTEventDispatcher.h"
#import "RCTLog.h"
#import "RCTRefreshControl.h"
#import "RCTUIManager.h"
#import "RCTUtils.h"
#import "UIView+Private.h"
#import "UIView+React.h"
CGFloat const ZINDEX_DEFAULT = 0;
CGFloat const ZINDEX_STICKY_HEADER = 50;
@interface RCTScrollEvent : NSObject <RCTEvent>
- (instancetype)initWithEventName:(NSString *)eventName
reactTag:(NSNumber *)reactTag
scrollView:(UIScrollView *)scrollView
userData:(NSDictionary *)userData
coalescingKey:(uint16_t)coalescingKey NS_DESIGNATED_INITIALIZER;
@end
@implementation RCTScrollEvent
{
UIScrollView *_scrollView;
NSDictionary *_userData;
uint16_t _coalescingKey;
}
@synthesize viewTag = _viewTag;
@synthesize eventName = _eventName;
- (instancetype)initWithEventName:(NSString *)eventName
reactTag:(NSNumber *)reactTag
scrollView:(UIScrollView *)scrollView
userData:(NSDictionary *)userData
coalescingKey:(uint16_t)coalescingKey
{
RCTAssertParam(reactTag);
if ((self = [super init])) {
_eventName = [eventName copy];
_viewTag = reactTag;
_scrollView = scrollView;
_userData = userData;
_coalescingKey = coalescingKey;
}
return self;
}
RCT_NOT_IMPLEMENTED(- (instancetype)init)
- (uint16_t)coalescingKey
{
return _coalescingKey;
}
- (NSDictionary *)body
{
NSDictionary *body = @{
@"contentOffset": @{
@"x": @(_scrollView.contentOffset.x),
@"y": @(_scrollView.contentOffset.y)
},
@"contentInset": @{
@"top": @(_scrollView.contentInset.top),
@"left": @(_scrollView.contentInset.left),
@"bottom": @(_scrollView.contentInset.bottom),
@"right": @(_scrollView.contentInset.right)
},
@"contentSize": @{
@"width": @(_scrollView.contentSize.width),
@"height": @(_scrollView.contentSize.height)
},
@"layoutMeasurement": @{
@"width": @(_scrollView.frame.size.width),
@"height": @(_scrollView.frame.size.height)
},
@"zoomScale": @(_scrollView.zoomScale ?: 1),
};
if (_userData) {
NSMutableDictionary *mutableBody = [body mutableCopy];
[mutableBody addEntriesFromDictionary:_userData];
body = mutableBody;
}
return body;
}
- (BOOL)canCoalesce
{
return YES;
}
- (RCTScrollEvent *)coalesceWithEvent:(RCTScrollEvent *)newEvent
{
NSArray<NSDictionary *> *updatedChildFrames = [_userData[@"updatedChildFrames"] arrayByAddingObjectsFromArray:newEvent->_userData[@"updatedChildFrames"]];
if (updatedChildFrames) {
NSMutableDictionary *userData = [newEvent->_userData mutableCopy];
userData[@"updatedChildFrames"] = updatedChildFrames;
newEvent->_userData = userData;
}
return newEvent;
}
+ (NSString *)moduleDotMethod
{
return @"RCTEventEmitter.receiveEvent";
}
- (NSArray *)arguments
{
return @[self.viewTag, RCTNormalizeInputEventName(self.eventName), [self body]];
}
@end
/**
* Include a custom scroll view subclass because we want to limit certain
* default UIKit behaviors such as textFields automatically scrolling
* scroll views that contain them and support sticky headers.
*/
@interface RCTCustomScrollView : UIScrollView<UIGestureRecognizerDelegate>
@property (nonatomic, copy) NSIndexSet *stickyHeaderIndices;
@property (nonatomic, assign) BOOL centerContent;
//@property (nonatomic, strong) RCTRefreshControl *refreshControl;
@property (nonatomic, strong) RCTRefreshControl *rctRefreshControl;
@end
@implementation RCTCustomScrollView
{
__weak UIView *_dockedHeaderView;
//RCTRefreshControl *_refreshControl;
}
- (instancetype)initWithFrame:(CGRect)frame
{
if ((self = [super initWithFrame:frame])) {
[self.panGestureRecognizer addTarget:self action:@selector(handleCustomPan:)];
}
return self;
}
- (UIView *)contentView
{
return ((RCTScrollView *)self.superview).contentView;
}
/**
* @return Whether or not the scroll view interaction should be blocked because
* JS was found to be the responder.
*/
- (BOOL)_shouldDisableScrollInteraction
{
// Since this may be called on every pan, we need to make sure to only climb
// the hierarchy on rare occasions.
UIView *JSResponder = [RCTUIManager JSResponder];
if (JSResponder && JSResponder != self.superview) {
BOOL superviewHasResponder = [self isDescendantOfView:JSResponder];
return superviewHasResponder;
}
return NO;
}
- (void)handleCustomPan:(__unused UIPanGestureRecognizer *)sender
{
if ([self _shouldDisableScrollInteraction] && ![[RCTUIManager JSResponder] isKindOfClass:[RCTScrollView class]]) {
self.panGestureRecognizer.enabled = NO;
self.panGestureRecognizer.enabled = YES;
// TODO: If mid bounce, animate the scroll view to a non-bounced position
// while disabling (but only if `stopScrollInteractionIfJSHasResponder` was
// called *during* a `pan`. Currently, it will just snap into place which
// is not so bad either.
// Another approach:
// self.scrollEnabled = NO;
// self.scrollEnabled = YES;
}
}
- (void)scrollRectToVisible:(__unused CGRect)rect animated:(__unused BOOL)animated
{
// noop
}
/**
* Returning `YES` cancels touches for the "inner" `view` and causes a scroll.
* Returning `NO` causes touches to be directed to that inner view and prevents
* the scroll view from scrolling.
*
* `YES` -> Allows scrolling.
* `NO` -> Doesn't allow scrolling.
*
* By default this returns NO for all views that are UIControls and YES for
* everything else. What that does is allows scroll views to scroll even when a
* touch started inside of a `UIControl` (`UIButton` etc). For React scroll
* views, we want the default to be the same behavior as `UIControl`s so we
* return `YES` by default. But there's one case where we want to block the
* scrolling no matter what: When JS believes it has its own responder lock on
* a view that is *above* the scroll view in the hierarchy. So we abuse this
* `touchesShouldCancelInContentView` API in order to stop the scroll view from
* scrolling in this case.
*
* We are not aware of *any* other solution to the problem because alternative
* approaches require that we disable the scrollview *before* touches begin or
* move. This approach (`touchesShouldCancelInContentView`) works even if the
* JS responder is set after touches start/move because
* `touchesShouldCancelInContentView` is called as soon as the scroll view has
* been touched and dragged *just* far enough to decide to begin the "drag"
* movement of the scroll interaction. Returning `NO`, will cause the drag
* operation to fail.
*
* `touchesShouldCancelInContentView` will stop the *initialization* of a
* scroll pan gesture and most of the time this is sufficient. On rare
* occasion, the scroll gesture would have already initialized right before JS
* notifies native of the JS responder being set. In order to recover from that
* timing issue we have a fallback that kills any ongoing pan gesture that
* occurs when native is notified of a JS responder.
*
* Note: Explicitly returning `YES`, instead of relying on the default fixes
* (at least) one bug where if you have a UIControl inside a UIScrollView and
* tap on the UIControl and then start dragging (to scroll), it won't scroll.
* Chat with andras for more details.
*
* In order to have this called, you must have delaysContentTouches set to NO
* (which is the not the `UIKit` default).
*/
- (BOOL)touchesShouldCancelInContentView:(__unused UIView *)view
{
//TODO: shouldn't this call super if _shouldDisableScrollInteraction returns NO?
return ![self _shouldDisableScrollInteraction];
}
/*
* Automatically centers the content such that if the content is smaller than the
* ScrollView, we force it to be centered, but when you zoom or the content otherwise
* becomes larger than the ScrollView, there is no padding around the content but it
* can still fill the whole view.
*/
- (void)setContentOffset:(CGPoint)contentOffset
{
UIView *contentView = [self contentView];
if (contentView && _centerContent) {
CGSize subviewSize = contentView.frame.size;
CGSize scrollViewSize = self.bounds.size;
if (subviewSize.width < scrollViewSize.width) {
contentOffset.x = -(scrollViewSize.width - subviewSize.width) / 2.0;
}
if (subviewSize.height < scrollViewSize.height) {
contentOffset.y = -(scrollViewSize.height - subviewSize.height) / 2.0;
}
}
super.contentOffset = contentOffset;
}
- (void)dockClosestSectionHeader
{
UIView *contentView = [self contentView];
CGFloat scrollTop = self.bounds.origin.y + self.contentInset.top;
// If the RefreshControl is refreshing, remove it's height so sticky headers are
// positioned properly when scrolling down while refreshing.
//if (self.refreshControl != nil && self.refreshControl.refreshing) {
// scrollTop -= self.refreshControl.frame.size.height;
//}
if (_rctRefreshControl != nil && _rctRefreshControl.refreshing) {
scrollTop -= _rctRefreshControl.frame.size.height;
}
// Find the section headers that need to be docked
__block UIView *previousHeader = nil;
__block UIView *currentHeader = nil;
__block UIView *nextHeader = nil;
NSUInteger subviewCount = contentView.reactSubviews.count;
[_stickyHeaderIndices enumerateIndexesWithOptions:0 usingBlock:
^(NSUInteger idx, BOOL *stop) {
// If the subviews are out of sync with the sticky header indices don't
// do anything.
if (idx >= subviewCount) {
*stop = YES;
return;
}
UIView *header = contentView.reactSubviews[idx];
// If nextHeader not yet found, search for docked headers
if (!nextHeader) {
CGFloat height = header.bounds.size.height;
CGFloat top = header.center.y - height * header.layer.anchorPoint.y;
if (top > scrollTop) {
nextHeader = header;
} else {
previousHeader = currentHeader;
currentHeader = header;
}
}
// Reset transforms for header views
header.transform = CGAffineTransformIdentity;
header.layer.zPosition = ZINDEX_DEFAULT;
}];
// If no docked header, bail out
if (!currentHeader) {
return;
}
// Adjust current header to hug the top of the screen
CGFloat currentFrameHeight = currentHeader.bounds.size.height;
CGFloat currentFrameTop = currentHeader.center.y - currentFrameHeight * currentHeader.layer.anchorPoint.y;
CGFloat yOffset = scrollTop - currentFrameTop;
if (nextHeader) {
// The next header nudges the current header out of the way when it reaches
// the top of the screen
CGFloat nextFrameHeight = nextHeader.bounds.size.height;
CGFloat nextFrameTop = nextHeader.center.y - nextFrameHeight * nextHeader.layer.anchorPoint.y;
CGFloat overlap = currentFrameHeight - (nextFrameTop - scrollTop);
yOffset -= MAX(0, overlap);
}
currentHeader.transform = CGAffineTransformMakeTranslation(0, yOffset);
currentHeader.layer.zPosition = ZINDEX_STICKY_HEADER;
_dockedHeaderView = currentHeader;
if (previousHeader) {
// The previous header sits right above the currentHeader's initial position
// so it scrolls away nicely once the currentHeader has locked into place
CGFloat previousFrameHeight = previousHeader.bounds.size.height;
CGFloat targetCenter = currentFrameTop - previousFrameHeight * (1.0 - previousHeader.layer.anchorPoint.y);
yOffset = targetCenter - previousHeader.center.y;
previousHeader.transform = CGAffineTransformMakeTranslation(0, yOffset);
previousHeader.layer.zPosition = ZINDEX_STICKY_HEADER;
}
}
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
if (_dockedHeaderView && [self pointInside:point withEvent:event]) {
CGPoint convertedPoint = [_dockedHeaderView convertPoint:point fromView:self];
UIView *hitView = [_dockedHeaderView hitTest:convertedPoint withEvent:event];
if (hitView) {
return hitView;
}
}
return [super hitTest:point withEvent:event];
}
- (void)setRctRefreshControl:(RCTRefreshControl *)refreshControl
{
/*
if (_refreshControl) {
[_refreshControl removeFromSuperview];
}
_refreshControl = refreshControl;
[self addSubview:_refreshControl];
*/
if (_rctRefreshControl) {
[_rctRefreshControl removeFromSuperview];
}
_rctRefreshControl = refreshControl;
[self addSubview:_rctRefreshControl];
}
@end
@implementation RCTScrollView
{
RCTEventDispatcher *_eventDispatcher;
RCTCustomScrollView *_scrollView;
UIView *_contentView;
NSTimeInterval _lastScrollDispatchTime;
NSMutableArray<NSValue *> *_cachedChildFrames;
BOOL _allowNextScrollNoMatterWhat;
CGRect _lastClippedToRect;
uint16_t _coalescingKey;
NSString *_lastEmittedEventName;
NSHashTable *_scrollListeners;
}
@synthesize nativeScrollDelegate = _nativeScrollDelegate;
- (instancetype)initWithEventDispatcher:(RCTEventDispatcher *)eventDispatcher
{
RCTAssertParam(eventDispatcher);
if ((self = [super initWithFrame:CGRectZero])) {
_eventDispatcher = eventDispatcher;
_scrollView = [[RCTCustomScrollView alloc] initWithFrame:CGRectZero];
_scrollView.delegate = self;
_scrollView.delaysContentTouches = NO;
_automaticallyAdjustContentInsets = YES;
_contentInset = UIEdgeInsetsZero;
_contentSize = CGSizeZero;
_lastClippedToRect = CGRectNull;
_scrollEventThrottle = 0.0;
_lastScrollDispatchTime = 0;
_cachedChildFrames = [NSMutableArray new];
_scrollListeners = [NSHashTable weakObjectsHashTable];
[self addSubview:_scrollView];
}
return self;
}
RCT_NOT_IMPLEMENTED(- (instancetype)initWithFrame:(CGRect)frame)
RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)aDecoder)
- (void)setRemoveClippedSubviews:(__unused BOOL)removeClippedSubviews
{
// Does nothing
}
- (void)insertReactSubview:(UIView *)view atIndex:(__unused NSInteger)atIndex
{
if ([view isKindOfClass:[RCTRefreshControl class]]) {
// _scrollView.refreshControl = (RCTRefreshControl*)view;
[_scrollView setRctRefreshControl:(RCTRefreshControl *)view];
} else {
RCTAssert(_contentView == nil, @"RCTScrollView may only contain a single subview");
_contentView = view;
[_scrollView addSubview:view];
}
}
- (void)removeReactSubview:(UIView *)subview
{
if ([subview isKindOfClass:[RCTRefreshControl class]]) {
//_scrollView.refreshControl = nil;
[_scrollView setRctRefreshControl:nil];
} else {
RCTAssert(_contentView == subview, @"Attempted to remove non-existent subview");
_contentView = nil;
[subview removeFromSuperview];
}
}
- (NSArray<UIView *> *)reactSubviews
{
//if (_contentView && _scrollView.refreshControl) {
// return @[_contentView, _scrollView.refreshControl];
//}
if (_contentView && _scrollView.rctRefreshControl) {
return @[_contentView, _scrollView.rctRefreshControl];
}
return _contentView ? @[_contentView] : @[];
}
- (BOOL)centerContent
{
return _scrollView.centerContent;
}
- (void)setCenterContent:(BOOL)centerContent
{
_scrollView.centerContent = centerContent;
}
- (NSIndexSet *)stickyHeaderIndices
{
return _scrollView.stickyHeaderIndices;
}
- (void)setStickyHeaderIndices:(NSIndexSet *)headerIndices
{
RCTAssert(_scrollView.contentSize.width <= self.frame.size.width,
@"sticky headers are not supported with horizontal scrolled views");
_scrollView.stickyHeaderIndices = headerIndices;
}
- (void)setClipsToBounds:(BOOL)clipsToBounds
{
super.clipsToBounds = clipsToBounds;
_scrollView.clipsToBounds = clipsToBounds;
}
- (void)dealloc
{
_scrollView.delegate = nil;
}
- (void)layoutSubviews
{
[super layoutSubviews];
RCTAssert(self.subviews.count == 1, @"we should only have exactly one subview");
RCTAssert([self.subviews lastObject] == _scrollView, @"our only subview should be a scrollview");
CGPoint originalOffset = _scrollView.contentOffset;
_scrollView.frame = self.bounds;
_scrollView.contentOffset = originalOffset;
// Adjust the refresh control frame if the scrollview layout changes.
// RCTRefreshControl *refreshControl = _scrollView.refreshControl;
RCTRefreshControl *refreshControl = _scrollView.rctRefreshControl;
if (refreshControl && refreshControl.refreshing) {
refreshControl.frame = (CGRect){_scrollView.contentOffset, {_scrollView.frame.size.width, refreshControl.frame.size.height}};
}
[self updateClippedSubviews];
}
- (void)updateClippedSubviews
{
// Find a suitable view to use for clipping
UIView *clipView = [self react_findClipView];
if (!clipView) {
return;
}
static const CGFloat leeway = 1.0;
const CGSize contentSize = _scrollView.contentSize;
const CGRect bounds = _scrollView.bounds;
const BOOL scrollsHorizontally = contentSize.width > bounds.size.width;
const BOOL scrollsVertically = contentSize.height > bounds.size.height;
const BOOL shouldClipAgain =
CGRectIsNull(_lastClippedToRect) ||
(scrollsHorizontally && (bounds.size.width < leeway || fabs(_lastClippedToRect.origin.x - bounds.origin.x) >= leeway)) ||
(scrollsVertically && (bounds.size.height < leeway || fabs(_lastClippedToRect.origin.y - bounds.origin.y) >= leeway));
if (shouldClipAgain) {
const CGRect clipRect = CGRectInset(clipView.bounds, -leeway, -leeway);
[self react_updateClippedSubviewsWithClipRect:clipRect relativeToView:clipView];
_lastClippedToRect = bounds;
}
}
- (void)setContentInset:(UIEdgeInsets)contentInset
{
CGPoint contentOffset = _scrollView.contentOffset;
_contentInset = contentInset;
[RCTView autoAdjustInsetsForView:self
withScrollView:_scrollView
updateOffset:NO];
_scrollView.contentOffset = contentOffset;
}
- (void)scrollToOffset:(CGPoint)offset
{
[self scrollToOffset:offset animated:YES];
}
- (void)scrollToOffset:(CGPoint)offset animated:(BOOL)animated
{
if (!CGPointEqualToPoint(_scrollView.contentOffset, offset)) {
// Ensure at least one scroll event will fire
_allowNextScrollNoMatterWhat = YES;
[_scrollView setContentOffset:offset animated:animated];
}
}
- (void)zoomToRect:(CGRect)rect animated:(BOOL)animated
{
[_scrollView zoomToRect:rect animated:animated];
}
- (void)refreshContentInset
{
[RCTView autoAdjustInsetsForView:self
withScrollView:_scrollView
updateOffset:YES];
}
#pragma mark - ScrollView delegate
#define RCT_SEND_SCROLL_EVENT(_eventName, _userData) { \
NSString *eventName = NSStringFromSelector(@selector(_eventName)); \
[self sendScrollEventWithName:eventName scrollView:_scrollView userData:_userData]; \
}
#define RCT_FORWARD_SCROLL_EVENT(call) \
for (NSObject<UIScrollViewDelegate> *scrollViewListener in _scrollListeners) { \
if ([scrollViewListener respondsToSelector:_cmd]) { \
[scrollViewListener call]; \
} \
}
#define RCT_SCROLL_EVENT_HANDLER(delegateMethod, eventName) \
- (void)delegateMethod:(UIScrollView *)scrollView \
{ \
RCT_SEND_SCROLL_EVENT(eventName, nil); \
RCT_FORWARD_SCROLL_EVENT(delegateMethod:scrollView); \
}
RCT_SCROLL_EVENT_HANDLER(scrollViewWillBeginDecelerating, onMomentumScrollBegin)
RCT_SCROLL_EVENT_HANDLER(scrollViewDidZoom, onScroll)
- (void)setNativeScrollDelegate:(NSObject<UIScrollViewDelegate> *)nativeScrollDelegate
{
if (nativeScrollDelegate != _nativeScrollDelegate) {
if (_nativeScrollDelegate) {
[_scrollListeners removeObject:_nativeScrollDelegate];
}
if (nativeScrollDelegate) {
[_scrollListeners addObject:nativeScrollDelegate];
}
_nativeScrollDelegate = nativeScrollDelegate;
}
}
- (void)addScrollListener:(NSObject<UIScrollViewDelegate> *)scrollListener
{
[_scrollListeners addObject:scrollListener];
}
- (void)removeScrollListener:(NSObject<UIScrollViewDelegate> *)scrollListener
{
if (scrollListener == _nativeScrollDelegate) {
[self setNativeScrollDelegate:nil];
} else {
[_scrollListeners removeObject:scrollListener];
}
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
[_scrollView dockClosestSectionHeader];
[self updateClippedSubviews];
NSTimeInterval now = CACurrentMediaTime();
/**
* TODO: this logic looks wrong, and it may be because it is. Currently, if _scrollEventThrottle
* is set to zero (the default), the "didScroll" event is only sent once per scroll, instead of repeatedly
* while scrolling as expected. However, if you "fix" that bug, ScrollView will generate repeated
* warnings, and behave strangely (ListView works fine however), so don't fix it unless you fix that too!
*/
if (_allowNextScrollNoMatterWhat ||
(_scrollEventThrottle > 0 && _scrollEventThrottle < (now - _lastScrollDispatchTime))) {
// Calculate changed frames
NSArray<NSDictionary *> *childFrames = [self calculateChildFramesData];
// Dispatch event
RCT_SEND_SCROLL_EVENT(onScroll, (@{@"updatedChildFrames": childFrames}));
// Update dispatch time
_lastScrollDispatchTime = now;
_allowNextScrollNoMatterWhat = NO;
}
RCT_FORWARD_SCROLL_EVENT(scrollViewDidScroll:scrollView);
}
- (NSArray<NSDictionary *> *)calculateChildFramesData
{
NSMutableArray<NSDictionary *> *updatedChildFrames = [NSMutableArray new];
[[_contentView reactSubviews] enumerateObjectsUsingBlock:
^(UIView *subview, NSUInteger idx, __unused BOOL *stop) {
// Check if new or changed
CGRect newFrame = subview.frame;
BOOL frameChanged = NO;
if (_cachedChildFrames.count <= idx) {
frameChanged = YES;
[_cachedChildFrames addObject:[NSValue valueWithCGRect:newFrame]];
} else if (!CGRectEqualToRect(newFrame, [_cachedChildFrames[idx] CGRectValue])) {
frameChanged = YES;
_cachedChildFrames[idx] = [NSValue valueWithCGRect:newFrame];
}
// Create JS frame object
if (frameChanged) {
[updatedChildFrames addObject: @{
@"index": @(idx),
@"x": @(newFrame.origin.x),
@"y": @(newFrame.origin.y),
@"width": @(newFrame.size.width),
@"height": @(newFrame.size.height),
}];
}
}];
return updatedChildFrames;
}
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
_allowNextScrollNoMatterWhat = YES; // Ensure next scroll event is recorded, regardless of throttle
RCT_SEND_SCROLL_EVENT(onScrollBeginDrag, nil);
RCT_FORWARD_SCROLL_EVENT(scrollViewWillBeginDragging:scrollView);
}
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset
{
// snapToInterval
// An alternative to enablePaging which allows setting custom stopping intervals,
// smaller than a full page size. Often seen in apps which feature horizonally
// scrolling items. snapToInterval does not enforce scrolling one interval at a time
// but guarantees that the scroll will stop at an interval point.
if (self.snapToInterval) {
CGFloat snapToIntervalF = (CGFloat)self.snapToInterval;
// Find which axis to snap
BOOL isHorizontal = (scrollView.contentSize.width > self.frame.size.width);
// What is the current offset?
CGFloat targetContentOffsetAlongAxis = isHorizontal ? targetContentOffset->x : targetContentOffset->y;
// Which direction is the scroll travelling?
CGPoint translation = [scrollView.panGestureRecognizer translationInView:scrollView];
CGFloat translationAlongAxis = isHorizontal ? translation.x : translation.y;
// Offset based on desired alignment
CGFloat frameLength = isHorizontal ? self.frame.size.width : self.frame.size.height;
CGFloat alignmentOffset = 0.0f;
if ([self.snapToAlignment isEqualToString: @"center"]) {
alignmentOffset = (frameLength * 0.5f) + (snapToIntervalF * 0.5f);
} else if ([self.snapToAlignment isEqualToString: @"end"]) {
alignmentOffset = frameLength;
}
// Pick snap point based on direction and proximity
NSInteger snapIndex = floor((targetContentOffsetAlongAxis + alignmentOffset) / snapToIntervalF);
snapIndex = (translationAlongAxis < 0) ? snapIndex + 1 : snapIndex;
CGFloat newTargetContentOffset = ( snapIndex * snapToIntervalF ) - alignmentOffset;
// Set new targetContentOffset
if (isHorizontal) {
targetContentOffset->x = newTargetContentOffset;
} else {
targetContentOffset->y = newTargetContentOffset;
}
}
NSDictionary *userData = @{
@"velocity": @{
@"x": @(velocity.x),
@"y": @(velocity.y)
},
@"targetContentOffset": @{
@"x": @(targetContentOffset->x),
@"y": @(targetContentOffset->y)
}
};
RCT_SEND_SCROLL_EVENT(onScrollEndDrag, userData);
RCT_FORWARD_SCROLL_EVENT(scrollViewWillEndDragging:scrollView withVelocity:velocity targetContentOffset:targetContentOffset);
}
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
RCT_FORWARD_SCROLL_EVENT(scrollViewDidEndDragging:scrollView willDecelerate:decelerate);
}
- (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(UIView *)view
{
RCT_SEND_SCROLL_EVENT(onScrollBeginDrag, nil);
RCT_FORWARD_SCROLL_EVENT(scrollViewWillBeginZooming:scrollView withView:view);
}
- (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(CGFloat)scale
{
RCT_SEND_SCROLL_EVENT(onScrollEndDrag, nil);
RCT_FORWARD_SCROLL_EVENT(scrollViewDidEndZooming:scrollView withView:view atScale:scale);
}
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
// Fire a final scroll event
_allowNextScrollNoMatterWhat = YES;
[self scrollViewDidScroll:scrollView];
// Fire the end deceleration event
RCT_SEND_SCROLL_EVENT(onMomentumScrollEnd, nil);
RCT_FORWARD_SCROLL_EVENT(scrollViewDidEndDecelerating:scrollView);
}
- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView
{
// Fire a final scroll event
_allowNextScrollNoMatterWhat = YES;
[self scrollViewDidScroll:scrollView];
// Fire the end deceleration event
RCT_SEND_SCROLL_EVENT(onMomentumScrollEnd, nil); //TODO: shouldn't this be onScrollAnimationEnd?
RCT_FORWARD_SCROLL_EVENT(scrollViewDidEndScrollingAnimation:scrollView);
}
- (BOOL)scrollViewShouldScrollToTop:(UIScrollView *)scrollView
{
for (NSObject<UIScrollViewDelegate> *scrollListener in _scrollListeners) {
if ([scrollListener respondsToSelector:_cmd] &&
![scrollListener scrollViewShouldScrollToTop:scrollView]) {
return NO;
}
}
return YES;
}
- (UIView *)viewForZoomingInScrollView:(__unused UIScrollView *)scrollView
{
return _contentView;
}
#pragma mark - Setters
- (CGSize)_calculateViewportSize
{
CGSize viewportSize = self.bounds.size;
if (_automaticallyAdjustContentInsets) {
UIEdgeInsets contentInsets = [RCTView contentInsetsForView:self];
viewportSize = CGSizeMake(self.bounds.size.width - contentInsets.left - contentInsets.right,
self.bounds.size.height - contentInsets.top - contentInsets.bottom);
}
return viewportSize;
}
- (CGPoint)calculateOffsetForContentSize:(CGSize)newContentSize
{
CGPoint oldOffset = _scrollView.contentOffset;
CGPoint newOffset = oldOffset;
CGSize oldContentSize = _scrollView.contentSize;
CGSize viewportSize = [self _calculateViewportSize];
BOOL fitsinViewportY = oldContentSize.height <= viewportSize.height && newContentSize.height <= viewportSize.height;
if (newContentSize.height < oldContentSize.height && !fitsinViewportY) {
CGFloat offsetHeight = oldOffset.y + viewportSize.height;
if (oldOffset.y < 0) {
// overscrolled on top, leave offset alone
} else if (offsetHeight > oldContentSize.height) {
// overscrolled on the bottom, preserve overscroll amount
newOffset.y = MAX(0, oldOffset.y - (oldContentSize.height - newContentSize.height));
} else if (offsetHeight > newContentSize.height) {
// offset falls outside of bounds, scroll back to end of list
newOffset.y = MAX(0, newContentSize.height - viewportSize.height);
}
}
BOOL fitsinViewportX = oldContentSize.width <= viewportSize.width && newContentSize.width <= viewportSize.width;
if (newContentSize.width < oldContentSize.width && !fitsinViewportX) {
CGFloat offsetHeight = oldOffset.x + viewportSize.width;
if (oldOffset.x < 0) {
// overscrolled at the beginning, leave offset alone
} else if (offsetHeight > oldContentSize.width && newContentSize.width > viewportSize.width) {
// overscrolled at the end, preserve overscroll amount as much as possible
newOffset.x = MAX(0, oldOffset.x - (oldContentSize.width - newContentSize.width));
} else if (offsetHeight > newContentSize.width) {
// offset falls outside of bounds, scroll back to end
newOffset.x = MAX(0, newContentSize.width - viewportSize.width);
}
}
// all other cases, offset doesn't change
return newOffset;
}
/**
* Once you set the `contentSize`, to a nonzero value, it is assumed to be
* managed by you, and we'll never automatically compute the size for you,
* unless you manually reset it back to {0, 0}
*/
- (CGSize)contentSize
{
if (!CGSizeEqualToSize(_contentSize, CGSizeZero)) {
return _contentSize;
} else if (!_contentView) {
return CGSizeZero;
} else {
CGSize singleSubviewSize = _contentView.frame.size;
CGPoint singleSubviewPosition = _contentView.frame.origin;
return (CGSize){
singleSubviewSize.width + singleSubviewPosition.x,
singleSubviewSize.height + singleSubviewPosition.y
};
}
}
- (void)reactBridgeDidFinishTransaction
{
CGSize contentSize = self.contentSize;
if (!CGSizeEqualToSize(_scrollView.contentSize, contentSize)) {
// When contentSize is set manually, ScrollView internals will reset
// contentOffset to {0, 0}. Since we potentially set contentSize whenever
// anything in the ScrollView updates, we workaround this issue by manually
// adjusting contentOffset whenever this happens
CGPoint newOffset = [self calculateOffsetForContentSize:contentSize];
_scrollView.contentSize = contentSize;
_scrollView.contentOffset = newOffset;
}
if (RCT_DEBUG) {
// Validate that sticky headers are not out of range.
NSUInteger subviewCount = _scrollView.contentView.reactSubviews.count;
NSUInteger lastIndex = NSNotFound;
if (_scrollView.stickyHeaderIndices != nil) {
lastIndex = _scrollView.stickyHeaderIndices.lastIndex;
}
if (lastIndex != NSNotFound && lastIndex >= subviewCount) {
RCTLogWarn(@"Sticky header index %zd was outside the range {0, %zd}",
lastIndex, subviewCount);
}
}
[_scrollView dockClosestSectionHeader];
}
// Note: setting several properties of UIScrollView has the effect of
// resetting its contentOffset to {0, 0}. To prevent this, we generate
// setters here that will record the contentOffset beforehand, and
// restore it after the property has been set.
#define RCT_SET_AND_PRESERVE_OFFSET(setter, getter, type) \
- (void)setter:(type)value \
{ \
CGPoint contentOffset = _scrollView.contentOffset; \
[_scrollView setter:value]; \
_scrollView.contentOffset = contentOffset; \
} \
- (type)getter \
{ \
return [_scrollView getter]; \
}
RCT_SET_AND_PRESERVE_OFFSET(setAlwaysBounceHorizontal, alwaysBounceHorizontal, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setAlwaysBounceVertical, alwaysBounceVertical, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setBounces, bounces, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setBouncesZoom, bouncesZoom, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setCanCancelContentTouches, canCancelContentTouches, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setDecelerationRate, decelerationRate, CGFloat)
RCT_SET_AND_PRESERVE_OFFSET(setDirectionalLockEnabled, isDirectionalLockEnabled, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setIndicatorStyle, indicatorStyle, UIScrollViewIndicatorStyle)
RCT_SET_AND_PRESERVE_OFFSET(setKeyboardDismissMode, keyboardDismissMode, UIScrollViewKeyboardDismissMode)
RCT_SET_AND_PRESERVE_OFFSET(setMaximumZoomScale, maximumZoomScale, CGFloat)
RCT_SET_AND_PRESERVE_OFFSET(setMinimumZoomScale, minimumZoomScale, CGFloat)
RCT_SET_AND_PRESERVE_OFFSET(setPagingEnabled, isPagingEnabled, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setScrollEnabled, isScrollEnabled, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setScrollsToTop, scrollsToTop, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setShowsHorizontalScrollIndicator, showsHorizontalScrollIndicator, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setShowsVerticalScrollIndicator, showsVerticalScrollIndicator, BOOL)
RCT_SET_AND_PRESERVE_OFFSET(setZoomScale, zoomScale, CGFloat);
RCT_SET_AND_PRESERVE_OFFSET(setScrollIndicatorInsets, scrollIndicatorInsets, UIEdgeInsets);
- (void)setOnRefreshStart:(RCTDirectEventBlock)onRefreshStart
{
if (!onRefreshStart) {
_onRefreshStart = nil;
_scrollView.refreshControl = nil;
return;
}
_onRefreshStart = [onRefreshStart copy];
if (!_scrollView.refreshControl) {
RCTRefreshControl *refreshControl = [RCTRefreshControl new];
[refreshControl addTarget:self action:@selector(refreshControlValueChanged) forControlEvents:UIControlEventValueChanged];
_scrollView.refreshControl = refreshControl;
}
}
- (void)refreshControlValueChanged
{
if (self.onRefreshStart) {
self.onRefreshStart(nil);
}
}
- (void)endRefreshing
{
[_scrollView.refreshControl endRefreshing];
}
- (void)sendScrollEventWithName:(NSString *)eventName
scrollView:(UIScrollView *)scrollView
userData:(NSDictionary *)userData
{
if (![_lastEmittedEventName isEqualToString:eventName]) {
_coalescingKey++;
_lastEmittedEventName = [eventName copy];
}
RCTScrollEvent *scrollEvent = [[RCTScrollEvent alloc] initWithEventName:eventName
reactTag:self.reactTag
scrollView:scrollView
userData:userData
coalescingKey:_coalescingKey];
[_eventDispatcher sendEvent:scrollEvent];
}
@end
@implementation RCTEventDispatcher (RCTScrollView)
- (void)sendFakeScrollEvent:(NSNumber *)reactTag
{
// Use the selector here in case the onScroll block property is ever renamed
NSString *eventName = NSStringFromSelector(@selector(onScroll));
RCTScrollEvent *fakeScrollEvent = [[RCTScrollEvent alloc] initWithEventName:eventName
reactTag:reactTag
scrollView:nil
userData:nil
coalescingKey:0];
[self sendEvent:fakeScrollEvent];
}
@end
@jadwer

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jadwer commented Nov 16, 2016

Ahhhh no mms, te amo we <3

@cfournel

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cfournel commented Feb 2, 2017

You made my day , thank you !!! i was facing the same issue with an app built on react-native 0.25.1

Scroll view are working again !

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