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RCTShadowText.m
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RCTShadowText.m
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/**
* 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 "RCTShadowText.h"
#import <React/RCTAccessibilityManager.h>
#import <React/RCTBridge.h>
#import <React/RCTConvert.h>
#import <React/RCTFont.h>
#import <React/RCTLog.h>
#import <React/RCTShadowView+Layout.h>
#import <React/RCTUIManager.h>
#import <React/RCTUtils.h>
#import "RCTShadowRawText.h"
#import "RCTText.h"
#import "RCTTextView.h"
NSString *const RCTIsHighlightedAttributeName = @"IsHighlightedAttributeName";
NSString *const RCTReactTagAttributeName = @"ReactTagAttributeName";
static NSString *const kShadowViewAttributeName = @"RCTShadowViewAttributeName";
static CGFloat const kAutoSizeWidthErrorMargin = 0.05f;
static CGFloat const kAutoSizeHeightErrorMargin = 0.025f;
static CGFloat const kAutoSizeGranularity = 0.001f;
@implementation RCTShadowText
{
NSTextStorage *_cachedTextStorage;
CGFloat _cachedTextStorageWidth;
CGFloat _cachedTextStorageWidthMode;
NSAttributedString *_cachedAttributedString;
CGFloat _effectiveLetterSpacing;
UIUserInterfaceLayoutDirection _cachedLayoutDirection;
}
static YGSize RCTMeasure(YGNodeRef node, float width, YGMeasureMode widthMode, float height, YGMeasureMode heightMode)
{
RCTShadowText *shadowText = (__bridge RCTShadowText *)YGNodeGetContext(node);
NSTextStorage *textStorage = [shadowText buildTextStorageForWidth:width widthMode:widthMode];
[shadowText calculateTextFrame:textStorage];
NSLayoutManager *layoutManager = textStorage.layoutManagers.firstObject;
NSTextContainer *textContainer = layoutManager.textContainers.firstObject;
CGSize computedSize = [layoutManager usedRectForTextContainer:textContainer].size;
YGSize result;
result.width = RCTCeilPixelValue(computedSize.width);
if (shadowText->_effectiveLetterSpacing < 0) {
result.width -= shadowText->_effectiveLetterSpacing;
}
result.height = RCTCeilPixelValue(computedSize.height);
return result;
}
- (instancetype)init
{
if ((self = [super init])) {
_fontSize = NAN;
_letterSpacing = NAN;
_isHighlighted = NO;
_textDecorationStyle = NSUnderlineStyleSingle;
_opacity = 1.0;
_cachedTextStorageWidth = -1;
_cachedTextStorageWidthMode = -1;
_fontSizeMultiplier = 1.0;
_textAlign = NSTextAlignmentNatural;
_writingDirection = NSWritingDirectionNatural;
_cachedLayoutDirection = UIUserInterfaceLayoutDirectionLeftToRight;
YGNodeSetMeasureFunc(self.yogaNode, RCTMeasure);
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(contentSizeMultiplierDidChange:)
name:RCTUIManagerWillUpdateViewsDueToContentSizeMultiplierChangeNotification
object:nil];
}
return self;
}
- (void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
- (NSString *)description
{
NSString *superDescription = super.description;
return [[superDescription substringToIndex:superDescription.length - 1] stringByAppendingFormat:@"; text: %@>", [self attributedString].string];
}
- (BOOL)isYogaLeafNode
{
return YES;
}
- (void)contentSizeMultiplierDidChange:(NSNotification *)note
{
YGNodeMarkDirty(self.yogaNode);
[self dirtyText];
}
- (NSDictionary<NSString *, id> *)processUpdatedProperties:(NSMutableSet<RCTApplierBlock> *)applierBlocks
parentProperties:(NSDictionary<NSString *, id> *)parentProperties
{
if ([[self reactSuperview] isKindOfClass:[RCTShadowText class]]) {
return parentProperties;
}
parentProperties = [super processUpdatedProperties:applierBlocks
parentProperties:parentProperties];
CGFloat availableWidth = self.availableSize.width;
NSNumber *parentTag = [[self reactSuperview] reactTag];
NSTextStorage *textStorage = [self buildTextStorageForWidth:availableWidth widthMode:YGMeasureModeExactly];
CGRect textFrame = [self calculateTextFrame:textStorage];
BOOL selectable = _selectable;
[applierBlocks addObject:^(NSDictionary<NSNumber *, UIView *> *viewRegistry) {
RCTText *view = (RCTText *)viewRegistry[self.reactTag];
view.textFrame = textFrame;
view.textStorage = textStorage;
view.selectable = selectable;
/**
* NOTE: this logic is included to support rich text editing inside multiline
* `<TextInput>` controls. It is required in order to ensure that the
* textStorage (aka attributed string) is copied over from the RCTShadowText
* to the RCTText view in time to be used to update the editable text content.
* TODO: we should establish a delegate relationship betweeen RCTTextView
* and its contaned RCTText element when they get inserted and get rid of this
*/
UIView *parentView = viewRegistry[parentTag];
if ([parentView respondsToSelector:@selector(performTextUpdate)]) {
[(RCTTextView *)parentView performTextUpdate];
}
}];
return parentProperties;
}
- (void)applyLayoutNode:(YGNodeRef)node
viewsWithNewFrame:(NSMutableSet<RCTShadowView *> *)viewsWithNewFrame
absolutePosition:(CGPoint)absolutePosition
{
[super applyLayoutNode:node viewsWithNewFrame:viewsWithNewFrame absolutePosition:absolutePosition];
[self dirtyPropagation];
}
- (void)applyLayoutToChildren:(YGNodeRef)node
viewsWithNewFrame:(NSMutableSet<RCTShadowView *> *)viewsWithNewFrame
absolutePosition:(CGPoint)absolutePosition
{
// Run layout on subviews.
CGFloat availableWidth = self.availableSize.width;
NSTextStorage *textStorage = [self buildTextStorageForWidth:availableWidth widthMode:YGMeasureModeExactly];
NSLayoutManager *layoutManager = textStorage.layoutManagers.firstObject;
NSTextContainer *textContainer = layoutManager.textContainers.firstObject;
NSRange glyphRange = [layoutManager glyphRangeForTextContainer:textContainer];
NSRange characterRange = [layoutManager characterRangeForGlyphRange:glyphRange actualGlyphRange:NULL];
[layoutManager.textStorage enumerateAttribute:kShadowViewAttributeName inRange:characterRange options:0 usingBlock:^(RCTShadowView *child, NSRange range, BOOL *_) {
if (child) {
YGNodeRef childNode = child.yogaNode;
float width = YGNodeStyleGetWidth(childNode).value;
float height = YGNodeStyleGetHeight(childNode).value;
if (YGFloatIsUndefined(width) || YGFloatIsUndefined(height)) {
RCTLogError(@"Views nested within a <Text> must have a width and height");
}
UIFont *font = [textStorage attribute:NSFontAttributeName atIndex:range.location effectiveRange:nil];
CGRect glyphRect = [layoutManager boundingRectForGlyphRange:range inTextContainer:textContainer];
CGRect childFrame = {{
RCTRoundPixelValue(glyphRect.origin.x),
RCTRoundPixelValue(glyphRect.origin.y + glyphRect.size.height - height + font.descender)
}, {
RCTRoundPixelValue(width),
RCTRoundPixelValue(height)
}};
NSRange truncatedGlyphRange = [layoutManager truncatedGlyphRangeInLineFragmentForGlyphAtIndex:range.location];
BOOL childIsTruncated = NSIntersectionRange(range, truncatedGlyphRange).length != 0;
[child collectUpdatedFrames:viewsWithNewFrame
withFrame:childFrame
hidden:childIsTruncated
absolutePosition:absolutePosition];
}
}];
}
- (NSTextStorage *)buildTextStorageForWidth:(CGFloat)width widthMode:(YGMeasureMode)widthMode
{
if (
_cachedTextStorage &&
(width == _cachedTextStorageWidth || (isnan(width) && isnan(_cachedTextStorageWidth))) &&
widthMode == _cachedTextStorageWidthMode &&
_cachedLayoutDirection == self.layoutDirection
) {
return _cachedTextStorage;
}
NSLayoutManager *layoutManager = [NSLayoutManager new];
NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:self.attributedString];
[textStorage addLayoutManager:layoutManager];
NSTextContainer *textContainer = [NSTextContainer new];
textContainer.lineFragmentPadding = 0.0;
if (_numberOfLines > 0) {
textContainer.lineBreakMode = _ellipsizeMode;
} else {
textContainer.lineBreakMode = NSLineBreakByClipping;
}
textContainer.maximumNumberOfLines = _numberOfLines;
textContainer.size = (CGSize){
widthMode == YGMeasureModeUndefined || isnan(width) ? CGFLOAT_MAX : width,
CGFLOAT_MAX
};
[layoutManager addTextContainer:textContainer];
[layoutManager ensureLayoutForTextContainer:textContainer];
_cachedTextStorageWidth = width;
_cachedTextStorageWidthMode = widthMode;
_cachedTextStorage = textStorage;
return textStorage;
}
- (void)dirtyText
{
[super dirtyText];
_cachedTextStorage = nil;
}
- (void)recomputeText
{
[self attributedString];
[self setTextComputed];
[self dirtyPropagation];
}
- (NSAttributedString *)attributedString
{
return [self _attributedStringWithFontFamily:nil
fontSize:nil
fontWeight:nil
fontStyle:nil
letterSpacing:nil
useBackgroundColor:NO
foregroundColor:self.color ?: [UIColor blackColor]
backgroundColor:self.backgroundColor
opacity:self.opacity];
}
- (NSAttributedString *)_attributedStringWithFontFamily:(NSString *)fontFamily
fontSize:(NSNumber *)fontSize
fontWeight:(NSString *)fontWeight
fontStyle:(NSString *)fontStyle
letterSpacing:(NSNumber *)letterSpacing
useBackgroundColor:(BOOL)useBackgroundColor
foregroundColor:(UIColor *)foregroundColor
backgroundColor:(UIColor *)backgroundColor
opacity:(CGFloat)opacity
{
if (
![self isTextDirty] &&
_cachedAttributedString &&
_cachedLayoutDirection == self.layoutDirection
) {
return _cachedAttributedString;
}
_cachedLayoutDirection = self.layoutDirection;
if (_fontSize && !isnan(_fontSize)) {
fontSize = @(_fontSize);
}
if (_fontWeight) {
fontWeight = _fontWeight;
}
if (_fontStyle) {
fontStyle = _fontStyle;
}
if (_fontFamily) {
fontFamily = _fontFamily;
}
if (!isnan(_letterSpacing)) {
letterSpacing = @(_letterSpacing);
}
_effectiveLetterSpacing = letterSpacing.doubleValue;
UIFont *font = [RCTFont updateFont:nil
withFamily:fontFamily
size:fontSize
weight:fontWeight
style:fontStyle
variant:_fontVariant
scaleMultiplier:_allowFontScaling ? _fontSizeMultiplier : 1.0];
CGFloat heightOfTallestSubview = 0.0;
NSMutableAttributedString *attributedString = [NSMutableAttributedString new];
for (RCTShadowView *child in [self reactSubviews]) {
if ([child isKindOfClass:[RCTShadowText class]]) {
RCTShadowText *shadowText = (RCTShadowText *)child;
[attributedString appendAttributedString:
[shadowText _attributedStringWithFontFamily:fontFamily
fontSize:fontSize
fontWeight:fontWeight
fontStyle:fontStyle
letterSpacing:letterSpacing
useBackgroundColor:YES
foregroundColor:shadowText.color ?: foregroundColor
backgroundColor:shadowText.backgroundColor ?: backgroundColor
opacity:opacity * shadowText.opacity]];
[child setTextComputed];
} else if ([child isKindOfClass:[RCTShadowRawText class]]) {
RCTShadowRawText *shadowRawText = (RCTShadowRawText *)child;
[attributedString appendAttributedString:[[NSAttributedString alloc] initWithString:shadowRawText.text ?: @""]];
[child setTextComputed];
} else {
float width = YGNodeStyleGetWidth(child.yogaNode).value;
float height = YGNodeStyleGetHeight(child.yogaNode).value;
if (YGFloatIsUndefined(width) || YGFloatIsUndefined(height)) {
RCTLogError(@"Views nested within a <Text> must have a width and height");
}
NSTextAttachment *attachment = [NSTextAttachment new];
attachment.bounds = (CGRect){CGPointZero, {width, height}};
NSMutableAttributedString *attachmentString = [NSMutableAttributedString new];
[attachmentString appendAttributedString:[NSAttributedString attributedStringWithAttachment:attachment]];
[attachmentString addAttribute:kShadowViewAttributeName value:child range:(NSRange){0, attachmentString.length}];
[attributedString appendAttributedString:attachmentString];
if (height > heightOfTallestSubview) {
heightOfTallestSubview = height;
}
// Don't call setTextComputed on this child. RCTTextManager takes care of
// processing inline UIViews.
}
}
[self _addAttribute:NSForegroundColorAttributeName
withValue:[foregroundColor colorWithAlphaComponent:CGColorGetAlpha(foregroundColor.CGColor) * opacity]
toAttributedString:attributedString];
if (_isHighlighted) {
[self _addAttribute:RCTIsHighlightedAttributeName withValue:@YES toAttributedString:attributedString];
}
if (useBackgroundColor && backgroundColor) {
[self _addAttribute:NSBackgroundColorAttributeName
withValue:[backgroundColor colorWithAlphaComponent:CGColorGetAlpha(backgroundColor.CGColor) * opacity]
toAttributedString:attributedString];
}
[self _addAttribute:NSFontAttributeName withValue:font toAttributedString:attributedString];
[self _addAttribute:NSKernAttributeName withValue:letterSpacing toAttributedString:attributedString];
[self _addAttribute:RCTReactTagAttributeName withValue:self.reactTag toAttributedString:attributedString];
[self _setParagraphStyleOnAttributedString:attributedString
fontLineHeight:font.lineHeight
heightOfTallestSubview:heightOfTallestSubview];
// create a non-mutable attributedString for use by the Text system which avoids copies down the line
_cachedAttributedString = [[NSAttributedString alloc] initWithAttributedString:attributedString];
YGNodeMarkDirty(self.yogaNode);
return _cachedAttributedString;
}
- (void)_addAttribute:(NSString *)attribute withValue:(id)attributeValue toAttributedString:(NSMutableAttributedString *)attributedString
{
[attributedString enumerateAttribute:attribute inRange:NSMakeRange(0, attributedString.length) options:0 usingBlock:^(id value, NSRange range, BOOL *stop) {
if (!value && attributeValue) {
[attributedString addAttribute:attribute value:attributeValue range:range];
}
}];
}
/*
* LineHeight works the same way line-height works in the web: if children and self have
* varying lineHeights, we simply take the max.
*/
- (void)_setParagraphStyleOnAttributedString:(NSMutableAttributedString *)attributedString
fontLineHeight:(CGFloat)fontLineHeight
heightOfTallestSubview:(CGFloat)heightOfTallestSubview
{
__block BOOL hasParagraphStyle = NO;
if (_lineHeight != 0.0 || _textAlign != NSTextAlignmentNatural) {
hasParagraphStyle = YES;
}
CGFloat fontSizeMultiplier = _allowFontScaling ? _fontSizeMultiplier : 1.0;
// Text line height
__block float compoundLineHeight = _lineHeight * fontSizeMultiplier;
// Checking for `maximumLineHeight` on each of our children and updating `compoundLineHeight` with the maximum value on the go.
[attributedString enumerateAttribute:NSParagraphStyleAttributeName
inRange:(NSRange){0, attributedString.length}
options:0
usingBlock:^(NSParagraphStyle *paragraphStyle, NSRange range, BOOL *stop) {
if (!paragraphStyle) {
return;
}
hasParagraphStyle = YES;
compoundLineHeight = MAX(compoundLineHeight, paragraphStyle.maximumLineHeight);
}];
compoundLineHeight = MAX(round(compoundLineHeight), ceilf(heightOfTallestSubview));
// Text alignment
NSTextAlignment textAlign = _textAlign;
if (textAlign == NSTextAlignmentRight || textAlign == NSTextAlignmentLeft) {
if (_cachedLayoutDirection == UIUserInterfaceLayoutDirectionRightToLeft) {
if (textAlign == NSTextAlignmentRight) {
textAlign = NSTextAlignmentLeft;
} else {
textAlign = NSTextAlignmentRight;
}
}
}
if (hasParagraphStyle) {
NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
paragraphStyle.alignment = textAlign;
paragraphStyle.baseWritingDirection = _writingDirection;
paragraphStyle.minimumLineHeight = compoundLineHeight;
paragraphStyle.maximumLineHeight = compoundLineHeight;
[attributedString addAttribute:NSParagraphStyleAttributeName
value:paragraphStyle
range:(NSRange){0, attributedString.length}];
if (compoundLineHeight > fontLineHeight) {
[attributedString addAttribute:NSBaselineOffsetAttributeName
value:@(compoundLineHeight / 2 - fontLineHeight / 2)
range:(NSRange){0, attributedString.length}];
}
}
// Text decoration
if (_textDecorationLine == RCTTextDecorationLineTypeUnderline ||
_textDecorationLine == RCTTextDecorationLineTypeUnderlineStrikethrough) {
[self _addAttribute:NSUnderlineStyleAttributeName withValue:@(_textDecorationStyle)
toAttributedString:attributedString];
}
if (_textDecorationLine == RCTTextDecorationLineTypeStrikethrough ||
_textDecorationLine == RCTTextDecorationLineTypeUnderlineStrikethrough){
[self _addAttribute:NSStrikethroughStyleAttributeName withValue:@(_textDecorationStyle)
toAttributedString:attributedString];
}
if (_textDecorationColor) {
[self _addAttribute:NSStrikethroughColorAttributeName withValue:_textDecorationColor
toAttributedString:attributedString];
[self _addAttribute:NSUnderlineColorAttributeName withValue:_textDecorationColor
toAttributedString:attributedString];
}
// Text shadow
if (!CGSizeEqualToSize(_textShadowOffset, CGSizeZero)) {
NSShadow *shadow = [NSShadow new];
shadow.shadowOffset = _textShadowOffset;
shadow.shadowBlurRadius = _textShadowRadius;
shadow.shadowColor = _textShadowColor;
[self _addAttribute:NSShadowAttributeName withValue:shadow toAttributedString:attributedString];
}
}
#pragma mark Autosizing
- (CGRect)calculateTextFrame:(NSTextStorage *)textStorage
{
CGRect textFrame = UIEdgeInsetsInsetRect((CGRect){CGPointZero, self.frame.size},
self.compoundInsets);
if (_adjustsFontSizeToFit) {
textFrame = [self updateStorage:textStorage toFitFrame:textFrame];
}
return textFrame;
}
- (CGRect)updateStorage:(NSTextStorage *)textStorage toFitFrame:(CGRect)frame
{
BOOL fits = [self attemptScale:1.0f
inStorage:textStorage
forFrame:frame];
CGSize requiredSize;
if (!fits) {
requiredSize = [self calculateOptimumScaleInFrame:frame
forStorage:textStorage
minScale:self.minimumFontScale
maxScale:1.0
prevMid:INT_MAX];
} else {
requiredSize = [self calculateSize:textStorage];
}
// Vertically center draw position for new text sizing.
frame.origin.y = self.compoundInsets.top + RCTRoundPixelValue((CGRectGetHeight(frame) - requiredSize.height) / 2.0f);
return frame;
}
- (CGSize)calculateOptimumScaleInFrame:(CGRect)frame
forStorage:(NSTextStorage *)textStorage
minScale:(CGFloat)minScale
maxScale:(CGFloat)maxScale
prevMid:(CGFloat)prevMid
{
CGFloat midScale = (minScale + maxScale) / 2.0f;
if (round((prevMid / kAutoSizeGranularity)) == round((midScale / kAutoSizeGranularity))) {
//Bail because we can't meet error margin.
return [self calculateSize:textStorage];
} else {
RCTSizeComparison comparison = [self attemptScale:midScale
inStorage:textStorage
forFrame:frame];
if (comparison == RCTSizeWithinRange) {
return [self calculateSize:textStorage];
} else if (comparison == RCTSizeTooLarge) {
return [self calculateOptimumScaleInFrame:frame
forStorage:textStorage
minScale:minScale
maxScale:midScale - kAutoSizeGranularity
prevMid:midScale];
} else {
return [self calculateOptimumScaleInFrame:frame
forStorage:textStorage
minScale:midScale + kAutoSizeGranularity
maxScale:maxScale
prevMid:midScale];
}
}
}
- (RCTSizeComparison)attemptScale:(CGFloat)scale
inStorage:(NSTextStorage *)textStorage
forFrame:(CGRect)frame
{
NSLayoutManager *layoutManager = [textStorage.layoutManagers firstObject];
NSTextContainer *textContainer = [layoutManager.textContainers firstObject];
NSRange glyphRange = NSMakeRange(0, textStorage.length);
[textStorage beginEditing];
[textStorage enumerateAttribute:NSFontAttributeName
inRange:glyphRange
options:0
usingBlock:^(UIFont *font, NSRange range, BOOL *stop)
{
if (font) {
UIFont *originalFont = [self.attributedString attribute:NSFontAttributeName
atIndex:range.location
effectiveRange:&range];
UIFont *newFont = [font fontWithSize:originalFont.pointSize * scale];
[textStorage removeAttribute:NSFontAttributeName range:range];
[textStorage addAttribute:NSFontAttributeName value:newFont range:range];
}
}];
[textStorage endEditing];
NSInteger linesRequired = [self numberOfLinesRequired:[textStorage.layoutManagers firstObject]];
CGSize requiredSize = [self calculateSize:textStorage];
BOOL fitSize = requiredSize.height <= CGRectGetHeight(frame) &&
requiredSize.width <= CGRectGetWidth(frame);
BOOL fitLines = linesRequired <= textContainer.maximumNumberOfLines ||
textContainer.maximumNumberOfLines == 0;
if (fitLines && fitSize) {
if ((requiredSize.width + (CGRectGetWidth(frame) * kAutoSizeWidthErrorMargin)) > CGRectGetWidth(frame) &&
(requiredSize.height + (CGRectGetHeight(frame) * kAutoSizeHeightErrorMargin)) > CGRectGetHeight(frame))
{
return RCTSizeWithinRange;
} else {
return RCTSizeTooSmall;
}
} else {
return RCTSizeTooLarge;
}
}
// Via Apple Text Layout Programming Guide
// https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/TextLayout/Tasks/CountLines.html
- (NSInteger)numberOfLinesRequired:(NSLayoutManager *)layoutManager
{
NSInteger numberOfLines, index, numberOfGlyphs = [layoutManager numberOfGlyphs];
NSRange lineRange;
for (numberOfLines = 0, index = 0; index < numberOfGlyphs; numberOfLines++){
(void) [layoutManager lineFragmentRectForGlyphAtIndex:index
effectiveRange:&lineRange];
index = NSMaxRange(lineRange);
}
return numberOfLines;
}
// Via Apple Text Layout Programming Guide
//https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/TextLayout/Tasks/StringHeight.html
- (CGSize)calculateSize:(NSTextStorage *)storage
{
NSLayoutManager *layoutManager = [storage.layoutManagers firstObject];
NSTextContainer *textContainer = [layoutManager.textContainers firstObject];
[textContainer setLineBreakMode:NSLineBreakByWordWrapping];
NSInteger maxLines = [textContainer maximumNumberOfLines];
[textContainer setMaximumNumberOfLines:0];
(void) [layoutManager glyphRangeForTextContainer:textContainer];
CGSize requiredSize = [layoutManager usedRectForTextContainer:textContainer].size;
[textContainer setMaximumNumberOfLines:maxLines];
return requiredSize;
}
#define RCT_TEXT_PROPERTY(setProp, ivar, type) \
- (void)set##setProp:(type)value; \
{ \
ivar = value; \
[self dirtyText]; \
}
RCT_TEXT_PROPERTY(AdjustsFontSizeToFit, _adjustsFontSizeToFit, BOOL)
RCT_TEXT_PROPERTY(Color, _color, UIColor *)
RCT_TEXT_PROPERTY(FontFamily, _fontFamily, NSString *)
RCT_TEXT_PROPERTY(FontSize, _fontSize, CGFloat)
RCT_TEXT_PROPERTY(FontWeight, _fontWeight, NSString *)
RCT_TEXT_PROPERTY(FontStyle, _fontStyle, NSString *)
RCT_TEXT_PROPERTY(FontVariant, _fontVariant, NSArray *)
RCT_TEXT_PROPERTY(IsHighlighted, _isHighlighted, BOOL)
RCT_TEXT_PROPERTY(LetterSpacing, _letterSpacing, CGFloat)
RCT_TEXT_PROPERTY(LineHeight, _lineHeight, CGFloat)
RCT_TEXT_PROPERTY(NumberOfLines, _numberOfLines, NSUInteger)
RCT_TEXT_PROPERTY(EllipsizeMode, _ellipsizeMode, NSLineBreakMode)
RCT_TEXT_PROPERTY(TextAlign, _textAlign, NSTextAlignment)
RCT_TEXT_PROPERTY(TextDecorationColor, _textDecorationColor, UIColor *);
RCT_TEXT_PROPERTY(TextDecorationLine, _textDecorationLine, RCTTextDecorationLineType);
RCT_TEXT_PROPERTY(TextDecorationStyle, _textDecorationStyle, NSUnderlineStyle);
RCT_TEXT_PROPERTY(WritingDirection, _writingDirection, NSWritingDirection)
RCT_TEXT_PROPERTY(Opacity, _opacity, CGFloat)
RCT_TEXT_PROPERTY(TextShadowOffset, _textShadowOffset, CGSize);
RCT_TEXT_PROPERTY(TextShadowRadius, _textShadowRadius, CGFloat);
RCT_TEXT_PROPERTY(TextShadowColor, _textShadowColor, UIColor *);
- (void)setAllowFontScaling:(BOOL)allowFontScaling
{
_allowFontScaling = allowFontScaling;
for (RCTShadowView *child in [self reactSubviews]) {
if ([child isKindOfClass:[RCTShadowText class]]) {
((RCTShadowText *)child).allowFontScaling = allowFontScaling;
}
}
[self dirtyText];
}
- (void)setFontSizeMultiplier:(CGFloat)fontSizeMultiplier
{
_fontSizeMultiplier = fontSizeMultiplier;
if (_fontSizeMultiplier == 0) {
RCTLogError(@"fontSizeMultiplier value must be > zero.");
_fontSizeMultiplier = 1.0;
}
for (RCTShadowView *child in [self reactSubviews]) {
if ([child isKindOfClass:[RCTShadowText class]]) {
((RCTShadowText *)child).fontSizeMultiplier = fontSizeMultiplier;
}
}
[self dirtyText];
}
- (void)setMinimumFontScale:(CGFloat)minimumFontScale
{
if (minimumFontScale >= 0.01) {
_minimumFontScale = minimumFontScale;
}
[self dirtyText];
}
@end