react-native/React/Views/RCTViewManager.m

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/**
* 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 "RCTViewManager.h"
#import "RCTBorderStyle.h"
#import "RCTBridge.h"
#import "RCTConvert.h"
#import "RCTEventDispatcher.h"
#import "RCTLog.h"
#import "RCTShadowView.h"
#import "RCTUIManager.h"
#import "RCTUIManagerUtils.h"
#import "RCTUtils.h"
#import "RCTView.h"
#import "UIView+React.h"
#import "RCTConvert+Transform.h"
#if TARGET_OS_TV
#import "RCTTVView.h"
#endif
@implementation RCTConvert(UIAccessibilityTraits)
RCT_MULTI_ENUM_CONVERTER(UIAccessibilityTraits, (@{
@"none": @(UIAccessibilityTraitNone),
@"button": @(UIAccessibilityTraitButton),
@"link": @(UIAccessibilityTraitLink),
@"header": @(UIAccessibilityTraitHeader),
@"search": @(UIAccessibilityTraitSearchField),
@"image": @(UIAccessibilityTraitImage),
@"selected": @(UIAccessibilityTraitSelected),
@"plays": @(UIAccessibilityTraitPlaysSound),
@"key": @(UIAccessibilityTraitKeyboardKey),
added accessibilityRole Prop, added functionality support for role on android Summary: Added a new property to View for Accessibility called `accessibilityRole`. This property merges functionality of existing properties: `accessibilityTraits` (iOS) and `accessibilityComponentType` (android). Currently, nine values are supported with equivalent behavior as `accessibilityTraits` (iOS) when `accessibilityRole` is set on iOS Voiceover and Android TalkBack ``` | 'none' | 'button' | 'link' | 'search' | 'image' | 'keyboardkey' | 'text' | 'adjustable' | 'tabbar' ``` They currently support similar behavior on talkback on Android and voice over on iOS Does not break functionality of existing properties, but have not tested for behavior of setting both this one and the old one. * iOS - I added a property accessibilityRoles, and basically remapped it to the same thing as accessibilityTraits. I also added in enum mappings for keyboardkey and tabbar. * Android - Also added a property accessibilityRoles, from the Android side. For the underlying native functionality, I built a helper class that is based off of AccessibilityRolesUtil.java from the accessibility team. Biggest changes made are that I defined my own enums if needed, and also set some properties to match the functionality of iOS Accessibility Traits. I also handled the logic for switch/case statements of setting roles for the android side on this file. Also, I currently haven't localized strings for setRoleDescription, but plan to. * Javascript - I added a view property accessibilityRoles in ViewPropTypes. Reviewed By: blavalla Differential Revision: D8756225 fbshipit-source-id: e03eec40cce86042551764f433e1defe7ee41b35
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@"keyboardkey": @(UIAccessibilityTraitKeyboardKey),
@"text": @(UIAccessibilityTraitStaticText),
@"summary": @(UIAccessibilityTraitSummaryElement),
@"disabled": @(UIAccessibilityTraitNotEnabled),
@"frequentUpdates": @(UIAccessibilityTraitUpdatesFrequently),
@"startsMedia": @(UIAccessibilityTraitStartsMediaSession),
@"adjustable": @(UIAccessibilityTraitAdjustable),
@"allowsDirectInteraction": @(UIAccessibilityTraitAllowsDirectInteraction),
@"pageTurn": @(UIAccessibilityTraitCausesPageTurn),
}), UIAccessibilityTraitNone, unsignedLongLongValue)
@end
@implementation RCTViewManager
@synthesize bridge = _bridge;
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RCT_EXPORT_MODULE()
- (dispatch_queue_t)methodQueue
{
return RCTGetUIManagerQueue();
}
- (UIView *)view
{
#if TARGET_OS_TV
return [RCTTVView new];
#else
return [RCTView new];
#endif
}
- (RCTShadowView *)shadowView
{
return [RCTShadowView new];
}
- (NSArray<NSString *> *)customBubblingEventTypes
{
return @[
// Generic events
@"press",
@"change",
@"focus",
@"blur",
@"submitEditing",
@"endEditing",
@"keyPress",
// Touch events
@"touchStart",
@"touchMove",
@"touchCancel",
@"touchEnd",
];
}
#pragma mark - View properties
#if TARGET_OS_TV
// Apple TV properties
RCT_EXPORT_VIEW_PROPERTY(isTVSelectable, BOOL)
RCT_EXPORT_VIEW_PROPERTY(hasTVPreferredFocus, BOOL)
RCT_EXPORT_VIEW_PROPERTY(tvParallaxProperties, NSDictionary)
#endif
RCT_EXPORT_VIEW_PROPERTY(nativeID, NSString)
// Acessibility related properties
RCT_REMAP_VIEW_PROPERTY(accessible, reactAccessibilityElement.isAccessibilityElement, BOOL)
RCT_REMAP_VIEW_PROPERTY(accessibilityActions, reactAccessibilityElement.accessibilityActions, NSString)
RCT_REMAP_VIEW_PROPERTY(accessibilityLabel, reactAccessibilityElement.accessibilityLabel, NSString)
RCT_REMAP_VIEW_PROPERTY(accessibilityTraits, reactAccessibilityElement.accessibilityTraits, UIAccessibilityTraits)
added accessibilityRole Prop, added functionality support for role on android Summary: Added a new property to View for Accessibility called `accessibilityRole`. This property merges functionality of existing properties: `accessibilityTraits` (iOS) and `accessibilityComponentType` (android). Currently, nine values are supported with equivalent behavior as `accessibilityTraits` (iOS) when `accessibilityRole` is set on iOS Voiceover and Android TalkBack ``` | 'none' | 'button' | 'link' | 'search' | 'image' | 'keyboardkey' | 'text' | 'adjustable' | 'tabbar' ``` They currently support similar behavior on talkback on Android and voice over on iOS Does not break functionality of existing properties, but have not tested for behavior of setting both this one and the old one. * iOS - I added a property accessibilityRoles, and basically remapped it to the same thing as accessibilityTraits. I also added in enum mappings for keyboardkey and tabbar. * Android - Also added a property accessibilityRoles, from the Android side. For the underlying native functionality, I built a helper class that is based off of AccessibilityRolesUtil.java from the accessibility team. Biggest changes made are that I defined my own enums if needed, and also set some properties to match the functionality of iOS Accessibility Traits. I also handled the logic for switch/case statements of setting roles for the android side on this file. Also, I currently haven't localized strings for setRoleDescription, but plan to. * Javascript - I added a view property accessibilityRoles in ViewPropTypes. Reviewed By: blavalla Differential Revision: D8756225 fbshipit-source-id: e03eec40cce86042551764f433e1defe7ee41b35
2018-07-10 19:09:02 +00:00
RCT_REMAP_VIEW_PROPERTY(accessibilityRole, reactAccessibilityElement.accessibilityTraits, UIAccessibilityTraits)
RCT_REMAP_VIEW_PROPERTY(accessibilityViewIsModal, reactAccessibilityElement.accessibilityViewIsModal, BOOL)
RCT_REMAP_VIEW_PROPERTY(accessibilityElementsHidden, reactAccessibilityElement.accessibilityElementsHidden, BOOL)
RCT_REMAP_VIEW_PROPERTY(accessibilityIgnoresInvertColors, reactAccessibilityElement.shouldAccessibilityIgnoresInvertColors, BOOL)
RCT_REMAP_VIEW_PROPERTY(onAccessibilityAction, reactAccessibilityElement.onAccessibilityAction, RCTDirectEventBlock)
RCT_REMAP_VIEW_PROPERTY(onAccessibilityTap, reactAccessibilityElement.onAccessibilityTap, RCTDirectEventBlock)
RCT_REMAP_VIEW_PROPERTY(onMagicTap, reactAccessibilityElement.onMagicTap, RCTDirectEventBlock)
RCT_REMAP_VIEW_PROPERTY(testID, reactAccessibilityElement.accessibilityIdentifier, NSString)
RCT_EXPORT_VIEW_PROPERTY(backgroundColor, UIColor)
RCT_REMAP_VIEW_PROPERTY(backfaceVisibility, layer.doubleSided, css_backface_visibility_t)
RCT_REMAP_VIEW_PROPERTY(opacity, alpha, CGFloat)
RCT_REMAP_VIEW_PROPERTY(shadowColor, layer.shadowColor, CGColor)
RCT_REMAP_VIEW_PROPERTY(shadowOffset, layer.shadowOffset, CGSize)
RCT_REMAP_VIEW_PROPERTY(shadowOpacity, layer.shadowOpacity, float)
RCT_REMAP_VIEW_PROPERTY(shadowRadius, layer.shadowRadius, CGFloat)
RCT_CUSTOM_VIEW_PROPERTY(overflow, YGOverflow, RCTView)
{
if (json) {
view.clipsToBounds = [RCTConvert YGOverflow:json] != YGOverflowVisible;
} else {
view.clipsToBounds = defaultView.clipsToBounds;
}
}
RCT_CUSTOM_VIEW_PROPERTY(shouldRasterizeIOS, BOOL, RCTView)
{
view.layer.shouldRasterize = json ? [RCTConvert BOOL:json] : defaultView.layer.shouldRasterize;
view.layer.rasterizationScale = view.layer.shouldRasterize ? [UIScreen mainScreen].scale : defaultView.layer.rasterizationScale;
}
RCT_CUSTOM_VIEW_PROPERTY(transform, CATransform3D, RCTView)
{
view.layer.transform = json ? [RCTConvert CATransform3D:json] : defaultView.layer.transform;
// TODO: Improve this by enabling edge antialiasing only for transforms with rotation or skewing
view.layer.allowsEdgeAntialiasing = !CATransform3DIsIdentity(view.layer.transform);
}
RCT_CUSTOM_VIEW_PROPERTY(pointerEvents, RCTPointerEvents, RCTView)
{
if ([view respondsToSelector:@selector(setPointerEvents:)]) {
view.pointerEvents = json ? [RCTConvert RCTPointerEvents:json] : defaultView.pointerEvents;
return;
}
if (!json) {
view.userInteractionEnabled = defaultView.userInteractionEnabled;
return;
}
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switch ([RCTConvert RCTPointerEvents:json]) {
case RCTPointerEventsUnspecified:
// Pointer events "unspecified" acts as if a stylesheet had not specified,
// which is different than "auto" in CSS (which cannot and will not be
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// supported in `React`. "auto" may override a parent's "none".
// Unspecified values do not.
// This wouldn't override a container view's `userInteractionEnabled = NO`
view.userInteractionEnabled = YES;
case RCTPointerEventsNone:
view.userInteractionEnabled = NO;
break;
default:
RCTLogError(@"UIView base class does not support pointerEvent value: %@", json);
}
}
RCT_CUSTOM_VIEW_PROPERTY(removeClippedSubviews, BOOL, RCTView)
{
if ([view respondsToSelector:@selector(setRemoveClippedSubviews:)]) {
view.removeClippedSubviews = json ? [RCTConvert BOOL:json] : defaultView.removeClippedSubviews;
}
}
RCT_CUSTOM_VIEW_PROPERTY(borderRadius, CGFloat, RCTView) {
if ([view respondsToSelector:@selector(setBorderRadius:)]) {
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view.borderRadius = json ? [RCTConvert CGFloat:json] : defaultView.borderRadius;
} else {
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view.layer.cornerRadius = json ? [RCTConvert CGFloat:json] : defaultView.layer.cornerRadius;
}
}
RCT_CUSTOM_VIEW_PROPERTY(borderColor, CGColor, RCTView)
{
if ([view respondsToSelector:@selector(setBorderColor:)]) {
view.borderColor = json ? [RCTConvert CGColor:json] : defaultView.borderColor;
} else {
view.layer.borderColor = json ? [RCTConvert CGColor:json] : defaultView.layer.borderColor;
}
}
RCT_CUSTOM_VIEW_PROPERTY(borderWidth, float, RCTView)
{
if ([view respondsToSelector:@selector(setBorderWidth:)]) {
view.borderWidth = json ? [RCTConvert CGFloat:json] : defaultView.borderWidth;
} else {
view.layer.borderWidth = json ? [RCTConvert CGFloat:json] : defaultView.layer.borderWidth;
}
}
RCT_CUSTOM_VIEW_PROPERTY(borderStyle, RCTBorderStyle, RCTView)
{
if ([view respondsToSelector:@selector(setBorderStyle:)]) {
view.borderStyle = json ? [RCTConvert RCTBorderStyle:json] : defaultView.borderStyle;
}
}
RCT_CUSTOM_VIEW_PROPERTY(hitSlop, UIEdgeInsets, RCTView)
{
if ([view respondsToSelector:@selector(setHitTestEdgeInsets:)]) {
if (json) {
UIEdgeInsets hitSlopInsets = [RCTConvert UIEdgeInsets:json];
view.hitTestEdgeInsets = UIEdgeInsetsMake(-hitSlopInsets.top, -hitSlopInsets.left, -hitSlopInsets.bottom, -hitSlopInsets.right);
} else {
view.hitTestEdgeInsets = defaultView.hitTestEdgeInsets;
}
}
}
#define RCT_VIEW_BORDER_PROPERTY(SIDE) \
RCT_CUSTOM_VIEW_PROPERTY(border##SIDE##Width, float, RCTView) \
{ \
if ([view respondsToSelector:@selector(setBorder##SIDE##Width:)]) { \
view.border##SIDE##Width = json ? [RCTConvert CGFloat:json] : defaultView.border##SIDE##Width; \
} \
} \
RCT_CUSTOM_VIEW_PROPERTY(border##SIDE##Color, UIColor, RCTView) \
{ \
if ([view respondsToSelector:@selector(setBorder##SIDE##Color:)]) { \
view.border##SIDE##Color = json ? [RCTConvert CGColor:json] : defaultView.border##SIDE##Color; \
} \
}
RCT_VIEW_BORDER_PROPERTY(Top)
RCT_VIEW_BORDER_PROPERTY(Right)
RCT_VIEW_BORDER_PROPERTY(Bottom)
RCT_VIEW_BORDER_PROPERTY(Left)
RCT_VIEW_BORDER_PROPERTY(Start)
RCT_VIEW_BORDER_PROPERTY(End)
#define RCT_VIEW_BORDER_RADIUS_PROPERTY(SIDE) \
RCT_CUSTOM_VIEW_PROPERTY(border##SIDE##Radius, CGFloat, RCTView) \
{ \
if ([view respondsToSelector:@selector(setBorder##SIDE##Radius:)]) { \
view.border##SIDE##Radius = json ? [RCTConvert CGFloat:json] : defaultView.border##SIDE##Radius; \
} \
} \
RCT_VIEW_BORDER_RADIUS_PROPERTY(TopLeft)
RCT_VIEW_BORDER_RADIUS_PROPERTY(TopRight)
RCT_VIEW_BORDER_RADIUS_PROPERTY(TopStart)
RCT_VIEW_BORDER_RADIUS_PROPERTY(TopEnd)
RCT_VIEW_BORDER_RADIUS_PROPERTY(BottomLeft)
RCT_VIEW_BORDER_RADIUS_PROPERTY(BottomRight)
RCT_VIEW_BORDER_RADIUS_PROPERTY(BottomStart)
RCT_VIEW_BORDER_RADIUS_PROPERTY(BottomEnd)
RCT_REMAP_VIEW_PROPERTY(display, reactDisplay, YGDisplay)
RCT_REMAP_VIEW_PROPERTY(zIndex, reactZIndex, NSInteger)
Implement CSS z-index for iOS Summary: This diff implement the CSS z-index for React Native iOS views. We've had numerous pull request for this feature, but they've all attempted to use the `layer.zPosition` property, which is problematic for two reasons: 1. zPosition only affects rendering order, not event processing order. Views with a higher zPosition will appear in front of others in the hierarchy, but won't be the first to receive touch events, and may be blocked by views that are visually behind them. 2. when using a perspective transform matrix, views with a nonzero zPosition will be rendered in a different position due to parallax, which probably isn't desirable. See https://github.com/facebook/react-native/pull/7825 for further discussion of this problem. So instead of using `layer.zPosition`, I've implemented this by actually adjusting the order of the subviews within their parent based on the zIndex. This can't be done on the JS side because it would affect layout, which is order-dependent, so I'm doing it inside the view itself. It works as follows: 1. The `reactSubviews` array is set, whose order matches the order of the JS components and shadowView components, as specified by the UIManager. 2. `didUpdateReactSubviews` is called, which in turn calls `sortedSubviews` (which lazily generates a sorted array of `reactSubviews` by zIndex) and inserts the result into the view. 3. If a subview is added or removed, or the zIndex of any subview is changed, the previous `sortedSubviews` array is cleared and `didUpdateReactSubviews` is called again. To demonstrate it working, I've modified the UIExplorer example from https://github.com/facebook/react-native/pull/7825 Reviewed By: javache Differential Revision: D3365717 fbshipit-source-id: b34aa8bfad577bce023f8af5414f9b974aafd8aa
2016-06-07 14:40:25 +00:00
#pragma mark - ShadowView properties
RCT_EXPORT_SHADOW_PROPERTY(top, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(right, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(start, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(end, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(bottom, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(left, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(width, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(height, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(minWidth, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(maxWidth, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(minHeight, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(maxHeight, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(borderTopWidth, float)
RCT_EXPORT_SHADOW_PROPERTY(borderRightWidth, float)
RCT_EXPORT_SHADOW_PROPERTY(borderBottomWidth, float)
RCT_EXPORT_SHADOW_PROPERTY(borderLeftWidth, float)
RCT_EXPORT_SHADOW_PROPERTY(borderStartWidth, float)
RCT_EXPORT_SHADOW_PROPERTY(borderEndWidth, float)
RCT_EXPORT_SHADOW_PROPERTY(borderWidth, float)
RCT_EXPORT_SHADOW_PROPERTY(marginTop, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(marginRight, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(marginBottom, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(marginLeft, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(marginStart, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(marginEnd, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(marginVertical, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(marginHorizontal, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(margin, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingTop, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingRight, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingBottom, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingLeft, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingStart, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingEnd, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingVertical, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(paddingHorizontal, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(padding, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(flex, float)
RCT_EXPORT_SHADOW_PROPERTY(flexGrow, float)
RCT_EXPORT_SHADOW_PROPERTY(flexShrink, float)
RCT_EXPORT_SHADOW_PROPERTY(flexBasis, YGValue)
RCT_EXPORT_SHADOW_PROPERTY(flexDirection, YGFlexDirection)
RCT_EXPORT_SHADOW_PROPERTY(flexWrap, YGWrap)
RCT_EXPORT_SHADOW_PROPERTY(justifyContent, YGJustify)
RCT_EXPORT_SHADOW_PROPERTY(alignItems, YGAlign)
RCT_EXPORT_SHADOW_PROPERTY(alignSelf, YGAlign)
RCT_EXPORT_SHADOW_PROPERTY(alignContent, YGAlign)
RCT_EXPORT_SHADOW_PROPERTY(position, YGPositionType)
RCT_EXPORT_SHADOW_PROPERTY(aspectRatio, float)
RCT_EXPORT_SHADOW_PROPERTY(overflow, YGOverflow)
RCT_EXPORT_SHADOW_PROPERTY(display, YGDisplay)
RCT_EXPORT_SHADOW_PROPERTY(onLayout, RCTDirectEventBlock)
[ReactNative] Introduce onLayout events Summary: Simply add an `onLayout` callback to a native view component, and the callback will be invoked with the current layout information when the view is mounted and whenever the layout changes. The only limitation is that scroll position and other stuff the layout system isn't aware of is not taken into account. This is because onLayout events wouldn't be triggered for these changes and if they are desired they should be tracked separately (e.g. with `onScroll`) and combined. Also fixes some bugs with LayoutAnimation callbacks. @public Test Plan: - Run new LayoutEventsExample in UIExplorer and see it work correctly. - New integration test passes internally (IntegrationTest project seems busted). - New jest test case passes. {F22318433} ``` 2015-05-06 15:45:05.848 [info][tid:com.facebook.React.JavaScript] "Running application "UIExplorerApp" with appParams: {"rootTag":1,"initialProps":{}}. __DEV__ === true, development-level warning are ON, performance optimizations are OFF" 2015-05-06 15:45:05.881 [info][tid:com.facebook.React.JavaScript] "received text layout event ", {"target":27,"layout":{"y":123,"x":12.5,"width":140.5,"height":18}} 2015-05-06 15:45:05.882 [info][tid:com.facebook.React.JavaScript] "received image layout event ", {"target":23,"layout":{"y":12.5,"x":122,"width":50,"height":50}} 2015-05-06 15:45:05.883 [info][tid:com.facebook.React.JavaScript] "received view layout event ", {"target":22,"layout":{"y":70.5,"x":20,"width":294,"height":204}} 2015-05-06 15:45:05.897 [info][tid:com.facebook.React.JavaScript] "received text layout event ", {"target":27,"layout":{"y":206.5,"x":12.5,"width":140.5,"height":18}} 2015-05-06 15:45:05.897 [info][tid:com.facebook.React.JavaScript] "received view layout event ", {"target":22,"layout":{"y":70.5,"x":20,"width":294,"height":287.5}} 2015-05-06 15:45:09.847 [info][tid:com.facebook.React.JavaScript] "layout animation done." 2015-05-06 15:45:09.847 [info][tid:com.facebook.React.JavaScript] "received image layout event ", {"target":23,"layout":{"y":12.5,"x":82,"width":50,"height":50}} 2015-05-06 15:45:09.848 [info][tid:com.facebook.React.JavaScript] "received view layout event ", {"target":22,"layout":{"y":110.5,"x":60,"width":214,"height":287.5}} 2015-05-06 15:45:09.862 [info][tid:com.facebook.React.JavaScript] "received text layout event ", {"target":27,"layout":{"y":206.5,"x":12.5,"width":120,"height":68}} 2015-05-06 15:45:09.863 [info][tid:com.facebook.React.JavaScript] "received image layout event ", {"target":23,"layout":{"y":12.5,"x":55,"width":50,"height":50}} 2015-05-06 15:45:09.863 [info][tid:com.facebook.React.JavaScript] "received view layout event ", {"target":22,"layout":{"y":128,"x":60,"width":160,"height":337.5}} ```
2015-05-07 19:11:02 +00:00
RCT_EXPORT_SHADOW_PROPERTY(direction, YGDirection)
Implement CSS z-index for iOS Summary: This diff implement the CSS z-index for React Native iOS views. We've had numerous pull request for this feature, but they've all attempted to use the `layer.zPosition` property, which is problematic for two reasons: 1. zPosition only affects rendering order, not event processing order. Views with a higher zPosition will appear in front of others in the hierarchy, but won't be the first to receive touch events, and may be blocked by views that are visually behind them. 2. when using a perspective transform matrix, views with a nonzero zPosition will be rendered in a different position due to parallax, which probably isn't desirable. See https://github.com/facebook/react-native/pull/7825 for further discussion of this problem. So instead of using `layer.zPosition`, I've implemented this by actually adjusting the order of the subviews within their parent based on the zIndex. This can't be done on the JS side because it would affect layout, which is order-dependent, so I'm doing it inside the view itself. It works as follows: 1. The `reactSubviews` array is set, whose order matches the order of the JS components and shadowView components, as specified by the UIManager. 2. `didUpdateReactSubviews` is called, which in turn calls `sortedSubviews` (which lazily generates a sorted array of `reactSubviews` by zIndex) and inserts the result into the view. 3. If a subview is added or removed, or the zIndex of any subview is changed, the previous `sortedSubviews` array is cleared and `didUpdateReactSubviews` is called again. To demonstrate it working, I've modified the UIExplorer example from https://github.com/facebook/react-native/pull/7825 Reviewed By: javache Differential Revision: D3365717 fbshipit-source-id: b34aa8bfad577bce023f8af5414f9b974aafd8aa
2016-06-07 14:40:25 +00:00
@end