// // ASTextNode.mm // AsyncDisplayKit // // Copyright (c) 2014-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 "ASTextNode.h" #import "ASTextNode+Beta.h" #include #import #import "_ASDisplayLayer.h" #import "ASDisplayNode+Subclasses.h" #import "ASDisplayNodeInternal.h" #import "ASHighlightOverlayLayer.h" #import "ASDisplayNodeExtras.h" #import "ASTextKitCoreTextAdditions.h" #import "ASTextKitRenderer+Positioning.h" #import "ASTextKitShadower.h" #import "ASInternalHelpers.h" #import "ASLayout.h" #import "CGRect+ASConvenience.h" static const NSTimeInterval ASTextNodeHighlightFadeOutDuration = 0.15; static const NSTimeInterval ASTextNodeHighlightFadeInDuration = 0.1; static const CGFloat ASTextNodeHighlightLightOpacity = 0.11; static const CGFloat ASTextNodeHighlightDarkOpacity = 0.22; static NSString *ASTextNodeTruncationTokenAttributeName = @"ASTextNodeTruncationAttribute"; struct ASTextNodeDrawParameter { CGRect bounds; UIColor *backgroundColor; }; @interface ASTextNode () @end @implementation ASTextNode { CGSize _shadowOffset; CGColorRef _shadowColor; UIColor *_cachedShadowUIColor; CGFloat _shadowOpacity; CGFloat _shadowRadius; UIEdgeInsets _textContainerInset; NSArray *_exclusionPaths; NSAttributedString *_composedTruncationText; NSString *_highlightedLinkAttributeName; id _highlightedLinkAttributeValue; ASTextNodeHighlightStyle _highlightStyle; NSRange _highlightRange; ASHighlightOverlayLayer *_activeHighlightLayer; CGSize _constrainedSize; ASTextKitRenderer *_renderer; ASTextNodeDrawParameter _drawParameter; UILongPressGestureRecognizer *_longPressGestureRecognizer; } @dynamic placeholderEnabled; #pragma mark - NSObject + (void)initialize { [super initialize]; if (self != [ASTextNode class]) { // Prevent custom drawing in subclasses ASDisplayNodeAssert(!ASSubclassOverridesClassSelector([ASTextNode class], self, @selector(drawRect:withParameters:isCancelled:isRasterizing:)), @"Subclass %@ must not override drawRect:withParameters:isCancelled:isRasterizing: method. Custom drawing in %@ subclass is not supported.", NSStringFromClass(self), NSStringFromClass([ASTextNode class])); } } static NSArray *DefaultLinkAttributeNames = @[ NSLinkAttributeName ]; - (instancetype)init { if (self = [super init]) { // Load default values from superclass. _shadowOffset = [super shadowOffset]; CGColorRef superColor = [super shadowColor]; if (superColor != NULL) { _shadowColor = CGColorRetain(superColor); } _shadowOpacity = [super shadowOpacity]; _shadowRadius = [super shadowRadius]; // Disable user interaction for text node by default. self.userInteractionEnabled = NO; self.needsDisplayOnBoundsChange = YES; _truncationMode = NSLineBreakByWordWrapping; _composedTruncationText = DefaultTruncationAttributedString(); // The common case is for a text node to be non-opaque and blended over some background. self.opaque = NO; self.backgroundColor = [UIColor clearColor]; self.linkAttributeNames = DefaultLinkAttributeNames; // Accessibility self.isAccessibilityElement = YES; self.accessibilityTraits = UIAccessibilityTraitStaticText; _constrainedSize = CGSizeMake(-INFINITY, -INFINITY); // Placeholders // Disabled by default in ASDisplayNode, but add a few options for those who toggle // on the special placeholder behavior of ASTextNode. _placeholderColor = ASDisplayNodeDefaultPlaceholderColor(); _placeholderInsets = UIEdgeInsetsMake(1.0, 0.0, 1.0, 0.0); } return self; } - (void)dealloc { if (_shadowColor != NULL) { CGColorRelease(_shadowColor); } [self _invalidateRenderer]; if (_longPressGestureRecognizer) { _longPressGestureRecognizer.delegate = nil; [_longPressGestureRecognizer removeTarget:nil action:NULL]; [self.view removeGestureRecognizer:_longPressGestureRecognizer]; } } - (NSString *)description { ASDN::MutexLocker l(__instanceLock__); NSString *plainString = [[_attributedText string] stringByTrimmingCharactersInSet:[NSCharacterSet newlineCharacterSet]]; NSString *truncationString = [_composedTruncationText string]; if (plainString.length > 50) plainString = [[plainString substringToIndex:50] stringByAppendingString:@"\u2026"]; return [NSString stringWithFormat:@"<%@: %p; text = \"%@\"; truncation string = \"%@\"; frame = %@; renderer = %p>", self.class, self, plainString, truncationString, self.nodeLoaded ? NSStringFromCGRect(self.layer.frame) : nil, _renderer]; } #pragma mark - ASDisplayNode // FIXME: Re-evaluate if it is still the right decision to clear the renderer at this stage. // This code was written before TextKit and when 512MB devices were still the overwhelming majority. - (void)displayDidFinish { [super displayDidFinish]; // We invalidate our renderer here to clear the very high memory cost of // keeping this around. _invalidateRenderer will dealloc this onto a bg // thread resulting in less stutters on the main thread than if it were // to be deallocated in dealloc. This is also helpful in opportunistically // reducing memory consumption and reducing the overall footprint of the app. [self _invalidateRenderer]; } - (void)clearContents { // We discard the backing store and renderer to prevent the very large // memory overhead of maintaining these for all text nodes. They can be // regenerated when layout is necessary. [super clearContents]; // ASDisplayNode will set layer.contents = nil [self _invalidateRenderer]; } - (void)didLoad { [super didLoad]; // If we are view-backed and the delegate cares, support the long-press callback. SEL longPressCallback = @selector(textNode:longPressedLinkAttribute:value:atPoint:textRange:); if (!self.isLayerBacked && [_delegate respondsToSelector:longPressCallback]) { _longPressGestureRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(_handleLongPress:)]; _longPressGestureRecognizer.cancelsTouchesInView = self.longPressCancelsTouches; _longPressGestureRecognizer.delegate = self; [self.view addGestureRecognizer:_longPressGestureRecognizer]; } } - (void)setFrame:(CGRect)frame { [super setFrame:frame]; [self _invalidateRendererIfNeededForBoundsSize:frame.size]; } - (void)setBounds:(CGRect)bounds { [super setBounds:bounds]; [self _invalidateRendererIfNeededForBoundsSize:bounds.size]; } #pragma mark - Renderer Management - (ASTextKitRenderer *)_renderer { return [self _rendererWithBounds:self.threadSafeBounds]; } - (ASTextKitRenderer *)_rendererWithBounds:(CGRect)bounds { ASDN::MutexLocker l(__instanceLock__); if (_renderer == nil) { CGSize constrainedSize; if (_constrainedSize.width != -INFINITY) { constrainedSize = _constrainedSize; } else { constrainedSize = bounds.size; constrainedSize.width -= (_textContainerInset.left + _textContainerInset.right); constrainedSize.height -= (_textContainerInset.top + _textContainerInset.bottom); } _renderer = [[ASTextKitRenderer alloc] initWithTextKitAttributes:[self _rendererAttributes] constrainedSize:constrainedSize]; } return _renderer; } - (ASTextKitAttributes)_rendererAttributes { ASDN::MutexLocker l(__instanceLock__); return { .attributedString = _attributedText, .truncationAttributedString = _composedTruncationText, .lineBreakMode = _truncationMode, .maximumNumberOfLines = _maximumNumberOfLines, .exclusionPaths = _exclusionPaths, // use the property getter so a subclass can provide these scale factors on demand if desired .pointSizeScaleFactors = self.pointSizeScaleFactors, .shadowOffset = _shadowOffset, .shadowColor = _cachedShadowUIColor, .shadowOpacity = _shadowOpacity, .shadowRadius = _shadowRadius }; } - (void)_invalidateRendererIfNeeded { [self _invalidateRendererIfNeededForBoundsSize:self.threadSafeBounds.size]; } - (void)_invalidateRendererIfNeededForBoundsSize:(CGSize)boundsSize { if ([self _needInvalidateRendererForBoundsSize:boundsSize]) { // Our bounds have changed to a size that is not identical to our constraining size, // so our previous layout information is invalid, and TextKit may draw at the // incorrect origin. { ASDN::MutexLocker l(__instanceLock__); _constrainedSize = CGSizeMake(-INFINITY, -INFINITY); } [self _invalidateRenderer]; } } - (void)_invalidateRenderer { ASDN::MutexLocker l(__instanceLock__); if (_renderer) { // Destruction of the layout managers/containers/text storage is quite // expensive, and can take some time, so we dispatch onto a bg queue to // actually dealloc. __block ASTextKitRenderer *renderer = _renderer; ASPerformBlockOnDeallocationQueue(^{ renderer = nil; }); _renderer = nil; } } #pragma mark - Layout and Sizing - (void)setTextContainerInset:(UIEdgeInsets)textContainerInset { ASDN::MutexLocker l(__instanceLock__); BOOL needsUpdate = !UIEdgeInsetsEqualToEdgeInsets(textContainerInset, _textContainerInset); if (needsUpdate) { _textContainerInset = textContainerInset; [self invalidateCalculatedLayout]; [self setNeedsLayout]; } } - (UIEdgeInsets)textContainerInset { ASDN::MutexLocker l(__instanceLock__); return _textContainerInset; } - (BOOL)_needInvalidateRendererForBoundsSize:(CGSize)boundsSize { ASDN::MutexLocker l(__instanceLock__); if (_renderer == nil) { return YES; } // If the size is not the same as the constraint we provided to the renderer, start out assuming we need // a new one. However, there are common cases where the constrained size doesn't need to be the same as calculated. CGSize rendererConstrainedSize = _renderer.constrainedSize; //inset bounds boundsSize.width -= _textContainerInset.left + _textContainerInset.right; boundsSize.height -= _textContainerInset.top + _textContainerInset.bottom; if (CGSizeEqualToSize(boundsSize, rendererConstrainedSize)) { return NO; } else { // It is very common to have a constrainedSize with a concrete, specific width but +Inf height. // In this case, as long as the text node has bounds as large as the full calculatedLayout suggests, // it means that the text has all the room it needs (as it was not vertically bounded). So, we will not // experience truncation and don't need to recreate the renderer with the size it already calculated, // as this would essentially serve to set its constrainedSize to be its calculatedSize (unnecessary). ASLayout *layout = self.calculatedLayout; if (layout != nil && CGSizeEqualToSize(boundsSize, layout.size)) { if (boundsSize.width != rendererConstrainedSize.width) { // Don't bother changing _constrainedSize, as ASDisplayNode's -measure: method would have a cache miss // and ask us to recalculate layout if it were called with the same calculatedSize that got us to this point! _renderer.constrainedSize = boundsSize; } return NO; } else { return YES; } } } - (void)calculatedLayoutDidChange { [super calculatedLayoutDidChange]; ASLayout *layout = self.calculatedLayout; if (layout != nil) { ASDN::MutexLocker l(__instanceLock__); CGSize layoutSize = layout.size; //Apply textContainerInset layoutSize.width -= (_textContainerInset.left + _textContainerInset.right); layoutSize.height -= (_textContainerInset.top + _textContainerInset.bottom); if (CGSizeEqualToSize(_constrainedSize, layoutSize) == NO) { _constrainedSize = layoutSize; _renderer.constrainedSize = layoutSize; } } } - (CGSize)calculateSizeThatFits:(CGSize)constrainedSize { ASDN::MutexLocker l(__instanceLock__); ASDisplayNodeAssert(constrainedSize.width >= 0, @"Constrained width for text (%f) is too narrow", constrainedSize.width); ASDisplayNodeAssert(constrainedSize.height >= 0, @"Constrained height for text (%f) is too short", constrainedSize.height); // Cache the original constrained size for final size calculateion CGSize originalConstrainedSize = constrainedSize; // Adjust constrainedSize for textContainerInset before assigning it constrainedSize.width -= (_textContainerInset.left + _textContainerInset.right); constrainedSize.height -= (_textContainerInset.top + _textContainerInset.bottom); _constrainedSize = constrainedSize; // Instead of invalidating the renderer, in case this is a new call with a different constrained size, // just update the size of the NSTextContainer that is owned by the renderer's internal context object. [self _renderer].constrainedSize = _constrainedSize; [self setNeedsDisplay]; CGSize size = [self _renderer].size; if (_attributedText.length > 0) { self.ascender = [[self class] ascenderWithAttributedString:_attributedText]; self.descender = [[_attributedText attribute:NSFontAttributeName atIndex:_attributedText.length - 1 effectiveRange:NULL] descender]; if (_renderer.currentScaleFactor > 0 && _renderer.currentScaleFactor < 1.0) { // while not perfect, this is a good estimate of what the ascender of the scaled font will be. self.ascender *= _renderer.currentScaleFactor; self.descender *= _renderer.currentScaleFactor; } } // Add the constrained size back textContainerInset size.width += (_textContainerInset.left + _textContainerInset.right); size.height += (_textContainerInset.top + _textContainerInset.bottom); return CGSizeMake(std::fmin(size.width, originalConstrainedSize.width), std::fmin(size.height, originalConstrainedSize.height)); } #pragma mark - Modifying User Text // Returns the ascender of the first character in attributedString by also including the line height if specified in paragraph style. + (CGFloat)ascenderWithAttributedString:(NSAttributedString *)attributedString { UIFont *font = [attributedString attribute:NSFontAttributeName atIndex:0 effectiveRange:NULL]; NSParagraphStyle *paragraphStyle = [attributedString attribute:NSParagraphStyleAttributeName atIndex:0 effectiveRange:NULL]; if (!paragraphStyle) { return font.ascender; } CGFloat lineHeight = MAX(font.lineHeight, paragraphStyle.minimumLineHeight); if (paragraphStyle.maximumLineHeight > 0) { lineHeight = MIN(lineHeight, paragraphStyle.maximumLineHeight); } return lineHeight + font.descender; } - (void)setAttributedText:(NSAttributedString *)attributedText { if (attributedText == nil) { attributedText = [[NSAttributedString alloc] initWithString:@"" attributes:nil]; } // Don't hold textLock for too long. { ASDN::MutexLocker l(__instanceLock__); if (ASObjectIsEqual(attributedText, _attributedText)) { return; } _attributedText = ASCleanseAttributedStringOfCoreTextAttributes(attributedText); // Sync the truncation string with attributes from the updated _attributedString // Without this, the size calculation of the text with truncation applied will // not take into account the attributes of attributedText in the last line [self _updateComposedTruncationText]; // We need an entirely new renderer [self _invalidateRenderer]; } NSUInteger length = attributedText.length; if (length > 0) { self.ascender = [[self class] ascenderWithAttributedString:attributedText]; self.descender = [[attributedText attribute:NSFontAttributeName atIndex:attributedText.length - 1 effectiveRange:NULL] descender]; } // Tell the display node superclasses that the cached layout is incorrect now [self invalidateCalculatedLayout]; // Force display to create renderer with new size and redisplay with new string [self setNeedsDisplay]; // Accessiblity self.accessibilityLabel = attributedText.string; self.isAccessibilityElement = (length != 0); // We're an accessibility element by default if there is a string. } #pragma mark - Text Layout - (void)setExclusionPaths:(NSArray *)exclusionPaths { ASDN::MutexLocker l(__instanceLock__); if (ASObjectIsEqual(exclusionPaths, _exclusionPaths)) { return; } _exclusionPaths = [exclusionPaths copy]; [self _invalidateRenderer]; [self invalidateCalculatedLayout]; [self setNeedsDisplay]; } - (NSArray *)exclusionPaths { ASDN::MutexLocker l(__instanceLock__); return _exclusionPaths; } #pragma mark - Drawing - (NSObject *)drawParametersForAsyncLayer:(_ASDisplayLayer *)layer { ASDN::MutexLocker l(__instanceLock__); _drawParameter = { .backgroundColor = self.backgroundColor, .bounds = self.bounds }; return nil; } - (void)drawRect:(CGRect)bounds withParameters:(id )p isCancelled:(asdisplaynode_iscancelled_block_t)isCancelledBlock isRasterizing:(BOOL)isRasterizing; { ASDN::MutexLocker l(__instanceLock__); ASTextNodeDrawParameter drawParameter = _drawParameter; CGRect drawParameterBounds = drawParameter.bounds; UIColor *backgroundColor = isRasterizing ? nil : drawParameter.backgroundColor; CGContextRef context = UIGraphicsGetCurrentContext(); ASDisplayNodeAssert(context, @"This is no good without a context."); CGContextSaveGState(context); CGContextTranslateCTM(context, _textContainerInset.left, _textContainerInset.top); ASTextKitRenderer *renderer = [self _rendererWithBounds:drawParameterBounds]; UIEdgeInsets shadowPadding = [self shadowPaddingWithRenderer:renderer]; CGPoint boundsOrigin = drawParameterBounds.origin; CGPoint textOrigin = CGPointMake(boundsOrigin.x - shadowPadding.left, boundsOrigin.y - shadowPadding.top); // Fill background if (backgroundColor != nil) { [backgroundColor setFill]; UIRectFillUsingBlendMode(CGContextGetClipBoundingBox(context), kCGBlendModeCopy); } // Draw shadow [renderer.shadower setShadowInContext:context]; // Draw text bounds.origin = textOrigin; [renderer drawInContext:context bounds:bounds]; CGContextRestoreGState(context); } #pragma mark - Attributes - (id)linkAttributeValueAtPoint:(CGPoint)point attributeName:(out NSString **)attributeNameOut range:(out NSRange *)rangeOut { return [self _linkAttributeValueAtPoint:point attributeName:attributeNameOut range:rangeOut inAdditionalTruncationMessage:NULL forHighlighting:NO]; } - (id)_linkAttributeValueAtPoint:(CGPoint)point attributeName:(out NSString **)attributeNameOut range:(out NSRange *)rangeOut inAdditionalTruncationMessage:(out BOOL *)inAdditionalTruncationMessageOut forHighlighting:(BOOL)highlighting { ASDisplayNodeAssertMainThread(); ASDN::MutexLocker l(__instanceLock__); ASTextKitRenderer *renderer = [self _renderer]; NSRange visibleRange = renderer.firstVisibleRange; NSAttributedString *attributedString = _attributedText; NSRange clampedRange = NSIntersectionRange(visibleRange, NSMakeRange(0, attributedString.length)); // Check in a 9-point region around the actual touch point so we make sure // we get the best attribute for the touch. __block CGFloat minimumGlyphDistance = CGFLOAT_MAX; // Final output vars __block id linkAttributeValue = nil; __block BOOL inTruncationMessage = NO; [renderer enumerateTextIndexesAtPosition:point usingBlock:^(NSUInteger characterIndex, CGRect glyphBoundingRect, BOOL *stop) { CGPoint glyphLocation = CGPointMake(CGRectGetMidX(glyphBoundingRect), CGRectGetMidY(glyphBoundingRect)); CGFloat currentDistance = std::sqrt(std::pow(point.x - glyphLocation.x, 2.f) + std::pow(point.y - glyphLocation.y, 2.f)); if (currentDistance >= minimumGlyphDistance) { // If the distance computed from the touch to the glyph location is // not the minimum among the located link attributes, we can just skip // to the next location. return; } // Check if it's outside the visible range, if so, then we mark this touch // as inside the truncation message, because in at least one of the touch // points it was. if (!(NSLocationInRange(characterIndex, visibleRange))) { inTruncationMessage = YES; } if (inAdditionalTruncationMessageOut != NULL) { *inAdditionalTruncationMessageOut = inTruncationMessage; } // Short circuit here if it's just in the truncation message. Since the // truncation message may be beyond the scope of the actual input string, // we have to make sure that we don't start asking for attributes on it. if (inTruncationMessage) { return; } for (NSString *attributeName in _linkAttributeNames) { NSRange range; id value = [attributedString attribute:attributeName atIndex:characterIndex longestEffectiveRange:&range inRange:clampedRange]; NSString *name = attributeName; if (value == nil || name == nil) { // Didn't find anything continue; } // If highlighting, check with delegate first. If not implemented, assume YES. if (highlighting && [_delegate respondsToSelector:@selector(textNode:shouldHighlightLinkAttribute:value:atPoint:)] && ![_delegate textNode:self shouldHighlightLinkAttribute:name value:value atPoint:point]) { value = nil; name = nil; } if (value != nil || name != nil) { // We found a minimum glyph distance link attribute, so set the min // distance, and the out params. minimumGlyphDistance = currentDistance; if (rangeOut != NULL && value != nil) { *rangeOut = range; // Limit to only the visible range, because the attributed string will // return values outside the visible range. if (NSMaxRange(*rangeOut) > NSMaxRange(visibleRange)) { (*rangeOut).length = MAX(NSMaxRange(visibleRange) - (*rangeOut).location, 0); } } if (attributeNameOut != NULL) { *attributeNameOut = name; } // Set the values for the next iteration linkAttributeValue = value; break; } } }]; return linkAttributeValue; } #pragma mark - UIGestureRecognizerDelegate - (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer { ASDisplayNodeAssertMainThread(); if (gestureRecognizer == _longPressGestureRecognizer) { // Don't allow long press on truncation message if ([self _pendingTruncationTap]) { return NO; } // Ask our delegate if a long-press on an attribute is relevant if ([_delegate respondsToSelector:@selector(textNode:shouldLongPressLinkAttribute:value:atPoint:)]) { return [_delegate textNode:self shouldLongPressLinkAttribute:_highlightedLinkAttributeName value:_highlightedLinkAttributeValue atPoint:[gestureRecognizer locationInView:self.view]]; } // Otherwise we are good to go. return YES; } if (([self _pendingLinkTap] || [self _pendingTruncationTap]) && [gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]] && CGRectContainsPoint(self.threadSafeBounds, [gestureRecognizer locationInView:self.view])) { return NO; } return [super gestureRecognizerShouldBegin:gestureRecognizer]; } #pragma mark - Highlighting - (ASTextNodeHighlightStyle)highlightStyle { ASDN::MutexLocker l(__instanceLock__); return _highlightStyle; } - (void)setHighlightStyle:(ASTextNodeHighlightStyle)highlightStyle { ASDN::MutexLocker l(__instanceLock__); _highlightStyle = highlightStyle; } - (NSRange)highlightRange { ASDisplayNodeAssertMainThread(); return _highlightRange; } - (void)setHighlightRange:(NSRange)highlightRange { [self setHighlightRange:highlightRange animated:NO]; } - (void)setHighlightRange:(NSRange)highlightRange animated:(BOOL)animated { [self _setHighlightRange:highlightRange forAttributeName:nil value:nil animated:animated]; } - (void)_setHighlightRange:(NSRange)highlightRange forAttributeName:(NSString *)highlightedAttributeName value:(id)highlightedAttributeValue animated:(BOOL)animated { ASDisplayNodeAssertMainThread(); _highlightedLinkAttributeName = highlightedAttributeName; _highlightedLinkAttributeValue = highlightedAttributeValue; if (!NSEqualRanges(highlightRange, _highlightRange) && ((0 != highlightRange.length) || (0 != _highlightRange.length))) { _highlightRange = highlightRange; if (_activeHighlightLayer) { if (animated) { __weak CALayer *weakHighlightLayer = _activeHighlightLayer; _activeHighlightLayer = nil; weakHighlightLayer.opacity = 0.0; CFTimeInterval beginTime = CACurrentMediaTime(); CABasicAnimation *possibleFadeIn = (CABasicAnimation *)[weakHighlightLayer animationForKey:@"opacity"]; if (possibleFadeIn) { // Calculate when we should begin fading out based on the end of the fade in animation, // Also check to make sure that the new begin time hasn't already passed CGFloat newBeginTime = (possibleFadeIn.beginTime + possibleFadeIn.duration); if (newBeginTime > beginTime) { beginTime = newBeginTime; } } CABasicAnimation *fadeOut = [CABasicAnimation animationWithKeyPath:@"opacity"]; fadeOut.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]; fadeOut.fromValue = possibleFadeIn.toValue ? : @(((CALayer *)weakHighlightLayer.presentationLayer).opacity); fadeOut.toValue = @0.0; fadeOut.fillMode = kCAFillModeBoth; fadeOut.duration = ASTextNodeHighlightFadeOutDuration; fadeOut.beginTime = beginTime; dispatch_block_t prev = [CATransaction completionBlock]; [CATransaction setCompletionBlock:^{ [weakHighlightLayer removeFromSuperlayer]; }]; [weakHighlightLayer addAnimation:fadeOut forKey:fadeOut.keyPath]; [CATransaction setCompletionBlock:prev]; } else { [_activeHighlightLayer removeFromSuperlayer]; _activeHighlightLayer = nil; } } if (0 != highlightRange.length) { // Find layer in hierarchy that allows us to draw highlighting on. CALayer *highlightTargetLayer = self.layer; while (highlightTargetLayer != nil) { if (highlightTargetLayer.as_allowsHighlightDrawing) { break; } highlightTargetLayer = highlightTargetLayer.superlayer; } if (highlightTargetLayer != nil) { ASDN::MutexLocker l(__instanceLock__); NSArray *highlightRects = [[self _renderer] rectsForTextRange:highlightRange measureOption:ASTextKitRendererMeasureOptionBlock]; NSMutableArray *converted = [NSMutableArray arrayWithCapacity:highlightRects.count]; for (NSValue *rectValue in highlightRects) { UIEdgeInsets shadowPadding = _renderer.shadower.shadowPadding; CGRect rendererRect = ASTextNodeAdjustRenderRectForShadowPadding(rectValue.CGRectValue, shadowPadding); // The rects returned from renderer don't have `textContainerInset`, // as well as they are using the `constrainedSize` for layout, // so we can simply increase the rect by insets to get the full blown layout. rendererRect.size.width += _textContainerInset.left + _textContainerInset.right; rendererRect.size.height += _textContainerInset.top + _textContainerInset.bottom; CGRect highlightedRect = [self.layer convertRect:rendererRect toLayer:highlightTargetLayer]; // We set our overlay layer's frame to the bounds of the highlight target layer. // Offset highlight rects to avoid double-counting target layer's bounds.origin. highlightedRect.origin.x -= highlightTargetLayer.bounds.origin.x; highlightedRect.origin.y -= highlightTargetLayer.bounds.origin.y; [converted addObject:[NSValue valueWithCGRect:highlightedRect]]; } ASHighlightOverlayLayer *overlayLayer = [[ASHighlightOverlayLayer alloc] initWithRects:converted]; overlayLayer.highlightColor = [[self class] _highlightColorForStyle:self.highlightStyle]; overlayLayer.frame = highlightTargetLayer.bounds; overlayLayer.masksToBounds = NO; overlayLayer.opacity = [[self class] _highlightOpacityForStyle:self.highlightStyle]; [highlightTargetLayer addSublayer:overlayLayer]; if (animated) { CABasicAnimation *fadeIn = [CABasicAnimation animationWithKeyPath:@"opacity"]; fadeIn.fromValue = @0.0; fadeIn.toValue = @(overlayLayer.opacity); fadeIn.duration = ASTextNodeHighlightFadeInDuration; fadeIn.beginTime = CACurrentMediaTime(); [overlayLayer addAnimation:fadeIn forKey:fadeIn.keyPath]; } [overlayLayer setNeedsDisplay]; _activeHighlightLayer = overlayLayer; } } } } - (void)_clearHighlightIfNecessary { ASDisplayNodeAssertMainThread(); if ([self _pendingLinkTap] || [self _pendingTruncationTap]) { [self setHighlightRange:NSMakeRange(0, 0) animated:YES]; } } + (CGColorRef)_highlightColorForStyle:(ASTextNodeHighlightStyle)style { return [UIColor colorWithWhite:(style == ASTextNodeHighlightStyleLight ? 0.0 : 1.0) alpha:1.0].CGColor; } + (CGFloat)_highlightOpacityForStyle:(ASTextNodeHighlightStyle)style { return (style == ASTextNodeHighlightStyleLight) ? ASTextNodeHighlightLightOpacity : ASTextNodeHighlightDarkOpacity; } #pragma mark - Text rects static CGRect ASTextNodeAdjustRenderRectForShadowPadding(CGRect rendererRect, UIEdgeInsets shadowPadding) { rendererRect.origin.x -= shadowPadding.left; rendererRect.origin.y -= shadowPadding.top; return rendererRect; } - (NSArray *)rectsForTextRange:(NSRange)textRange { return [self _rectsForTextRange:textRange measureOption:ASTextKitRendererMeasureOptionCapHeight]; } - (NSArray *)highlightRectsForTextRange:(NSRange)textRange { return [self _rectsForTextRange:textRange measureOption:ASTextKitRendererMeasureOptionBlock]; } - (NSArray *)_rectsForTextRange:(NSRange)textRange measureOption:(ASTextKitRendererMeasureOption)measureOption { ASDN::MutexLocker l(__instanceLock__); NSArray *rects = [[self _renderer] rectsForTextRange:textRange measureOption:measureOption]; NSMutableArray *adjustedRects = [NSMutableArray array]; for (NSValue *rectValue in rects) { CGRect rect = [rectValue CGRectValue]; rect = ASTextNodeAdjustRenderRectForShadowPadding(rect, self.shadowPadding); NSValue *adjustedRectValue = [NSValue valueWithCGRect:rect]; [adjustedRects addObject:adjustedRectValue]; } return adjustedRects; } - (CGRect)trailingRect { ASDN::MutexLocker l(__instanceLock__); CGRect rect = [[self _renderer] trailingRect]; return ASTextNodeAdjustRenderRectForShadowPadding(rect, self.shadowPadding); } - (CGRect)frameForTextRange:(NSRange)textRange { ASDN::MutexLocker l(__instanceLock__); CGRect frame = [[self _renderer] frameForTextRange:textRange]; return ASTextNodeAdjustRenderRectForShadowPadding(frame, self.shadowPadding); } #pragma mark - Placeholders - (void)setPlaceholderColor:(UIColor *)placeholderColor { ASDN::MutexLocker l(__instanceLock__); _placeholderColor = placeholderColor; // prevent placeholders if we don't have a color self.placeholderEnabled = placeholderColor != nil; } - (UIImage *)placeholderImage { // FIXME: Replace this implementation with reusable CALayers that have .backgroundColor set. // This would completely eliminate the memory and performance cost of the backing store. CGSize size = self.calculatedSize; if ((size.width * size.height) < CGFLOAT_EPSILON) { return nil; } ASDN::MutexLocker l(__instanceLock__); UIGraphicsBeginImageContext(size); [self.placeholderColor setFill]; ASTextKitRenderer *renderer = [self _renderer]; NSRange visibleRange = renderer.firstVisibleRange; // cap height is both faster and creates less subpixel blending NSArray *lineRects = [self _rectsForTextRange:visibleRange measureOption:ASTextKitRendererMeasureOptionLineHeight]; // fill each line with the placeholder color for (NSValue *rectValue in lineRects) { CGRect lineRect = [rectValue CGRectValue]; CGRect fillBounds = CGRectIntegral(UIEdgeInsetsInsetRect(lineRect, self.placeholderInsets)); if (fillBounds.size.width > 0.0 && fillBounds.size.height > 0.0) { UIRectFill(fillBounds); } } UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return image; } #pragma mark - Touch Handling - (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event { ASDisplayNodeAssertMainThread(); if (!_passthroughNonlinkTouches) { return [super pointInside:point withEvent:event]; } NSRange range = NSMakeRange(0, 0); NSString *linkAttributeName = nil; BOOL inAdditionalTruncationMessage = NO; id linkAttributeValue = [self _linkAttributeValueAtPoint:point attributeName:&linkAttributeName range:&range inAdditionalTruncationMessage:&inAdditionalTruncationMessage forHighlighting:YES]; NSUInteger lastCharIndex = NSIntegerMax; BOOL linkCrossesVisibleRange = (lastCharIndex > range.location) && (lastCharIndex < NSMaxRange(range) - 1); if (inAdditionalTruncationMessage) { return YES; } else if (range.length && !linkCrossesVisibleRange && linkAttributeValue != nil && linkAttributeName != nil) { return YES; } else { return NO; } } - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { ASDisplayNodeAssertMainThread(); [super touchesBegan:touches withEvent:event]; CGPoint point = [[touches anyObject] locationInView:self.view]; NSRange range = NSMakeRange(0, 0); NSString *linkAttributeName = nil; BOOL inAdditionalTruncationMessage = NO; id linkAttributeValue = [self _linkAttributeValueAtPoint:point attributeName:&linkAttributeName range:&range inAdditionalTruncationMessage:&inAdditionalTruncationMessage forHighlighting:YES]; NSUInteger lastCharIndex = NSIntegerMax; BOOL linkCrossesVisibleRange = (lastCharIndex > range.location) && (lastCharIndex < NSMaxRange(range) - 1); if (inAdditionalTruncationMessage) { NSRange visibleRange = NSMakeRange(0, 0); { ASDN::MutexLocker l(__instanceLock__); visibleRange = [self _renderer].firstVisibleRange; } NSRange truncationMessageRange = [self _additionalTruncationMessageRangeWithVisibleRange:visibleRange]; [self _setHighlightRange:truncationMessageRange forAttributeName:ASTextNodeTruncationTokenAttributeName value:nil animated:YES]; } else if (range.length && !linkCrossesVisibleRange && linkAttributeValue != nil && linkAttributeName != nil) { [self _setHighlightRange:range forAttributeName:linkAttributeName value:linkAttributeValue animated:YES]; } } - (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event { ASDisplayNodeAssertMainThread(); [super touchesCancelled:touches withEvent:event]; [self _clearHighlightIfNecessary]; } - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { ASDisplayNodeAssertMainThread(); [super touchesEnded:touches withEvent:event]; if ([self _pendingLinkTap] && [_delegate respondsToSelector:@selector(textNode:tappedLinkAttribute:value:atPoint:textRange:)]) { CGPoint point = [[touches anyObject] locationInView:self.view]; [_delegate textNode:self tappedLinkAttribute:_highlightedLinkAttributeName value:_highlightedLinkAttributeValue atPoint:point textRange:_highlightRange]; } if ([self _pendingTruncationTap]) { if ([_delegate respondsToSelector:@selector(textNodeTappedTruncationToken:)]) { [_delegate textNodeTappedTruncationToken:self]; } } [self _clearHighlightIfNecessary]; } - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { ASDisplayNodeAssertMainThread(); [super touchesMoved:touches withEvent:event]; UITouch *touch = [touches anyObject]; CGPoint locationInView = [touch locationInView:self.view]; // on 3D Touch enabled phones, this gets fired with changes in force, and usually will get fired immediately after touchesBegan:withEvent: if (CGPointEqualToPoint([touch previousLocationInView:self.view], locationInView)) return; // If touch has moved out of the current highlight range, clear the highlight. if (_highlightRange.length > 0) { NSRange range = NSMakeRange(0, 0); [self _linkAttributeValueAtPoint:locationInView attributeName:NULL range:&range inAdditionalTruncationMessage:NULL forHighlighting:YES]; if (!NSEqualRanges(_highlightRange, range)) { [self _clearHighlightIfNecessary]; } } } - (void)_handleLongPress:(UILongPressGestureRecognizer *)longPressRecognizer { ASDisplayNodeAssertMainThread(); // Respond to long-press when it begins, not when it ends. if (longPressRecognizer.state == UIGestureRecognizerStateBegan) { if ([_delegate respondsToSelector:@selector(textNode:longPressedLinkAttribute:value:atPoint:textRange:)]) { CGPoint touchPoint = [_longPressGestureRecognizer locationInView:self.view]; [_delegate textNode:self longPressedLinkAttribute:_highlightedLinkAttributeName value:_highlightedLinkAttributeValue atPoint:touchPoint textRange:_highlightRange]; } } } - (BOOL)_pendingLinkTap { ASDN::MutexLocker l(__instanceLock__); return (_highlightedLinkAttributeValue != nil && ![self _pendingTruncationTap]) && _delegate != nil; } - (BOOL)_pendingTruncationTap { ASDN::MutexLocker l(__instanceLock__); return [_highlightedLinkAttributeName isEqualToString:ASTextNodeTruncationTokenAttributeName]; } #pragma mark - Shadow Properties - (CGColorRef)shadowColor { ASDN::MutexLocker l(__instanceLock__); return _shadowColor; } - (void)setShadowColor:(CGColorRef)shadowColor { ASDN::MutexLocker l(__instanceLock__); if (_shadowColor != shadowColor) { if (shadowColor != NULL) { CGColorRetain(shadowColor); } if (_shadowColor != NULL) { CGColorRelease(_shadowColor); } _shadowColor = shadowColor; _cachedShadowUIColor = [UIColor colorWithCGColor:shadowColor]; [self _invalidateRenderer]; [self setNeedsDisplay]; } } - (CGSize)shadowOffset { ASDN::MutexLocker l(__instanceLock__); return _shadowOffset; } - (void)setShadowOffset:(CGSize)shadowOffset { ASDN::MutexLocker l(__instanceLock__); if (!CGSizeEqualToSize(_shadowOffset, shadowOffset)) { _shadowOffset = shadowOffset; [self _invalidateRenderer]; [self setNeedsDisplay]; } } - (CGFloat)shadowOpacity { ASDN::MutexLocker l(__instanceLock__); return _shadowOpacity; } - (void)setShadowOpacity:(CGFloat)shadowOpacity { ASDN::MutexLocker l(__instanceLock__); if (_shadowOpacity != shadowOpacity) { _shadowOpacity = shadowOpacity; [self _invalidateRenderer]; [self setNeedsDisplay]; } } - (CGFloat)shadowRadius { ASDN::MutexLocker l(__instanceLock__); return _shadowRadius; } - (void)setShadowRadius:(CGFloat)shadowRadius { ASDN::MutexLocker l(__instanceLock__); if (_shadowRadius != shadowRadius) { _shadowRadius = shadowRadius; [self _invalidateRenderer]; [self setNeedsDisplay]; } } - (UIEdgeInsets)shadowPadding { return [self shadowPaddingWithRenderer:[self _renderer]]; } - (UIEdgeInsets)shadowPaddingWithRenderer:(ASTextKitRenderer *)renderer { ASDN::MutexLocker l(__instanceLock__); return renderer.shadower.shadowPadding; } #pragma mark - Truncation Message static NSAttributedString *DefaultTruncationAttributedString() { static NSAttributedString *defaultTruncationAttributedString; static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ defaultTruncationAttributedString = [[NSAttributedString alloc] initWithString:NSLocalizedString(@"\u2026", @"Default truncation string")]; }); return defaultTruncationAttributedString; } - (void)setTruncationAttributedText:(NSAttributedString *)truncationAttributedText { ASDN::MutexLocker l(__instanceLock__); if (ASObjectIsEqual(_truncationAttributedText, truncationAttributedText)) { return; } _truncationAttributedText = [truncationAttributedText copy]; [self _invalidateTruncationText]; } - (void)setAdditionalTruncationMessage:(NSAttributedString *)additionalTruncationMessage { ASDN::MutexLocker l(__instanceLock__); if (ASObjectIsEqual(_additionalTruncationMessage, additionalTruncationMessage)) { return; } _additionalTruncationMessage = [additionalTruncationMessage copy]; [self _invalidateTruncationText]; } - (void)setTruncationMode:(NSLineBreakMode)truncationMode { ASDN::MutexLocker l(__instanceLock__); if (_truncationMode != truncationMode) { _truncationMode = truncationMode; [self _invalidateRenderer]; [self setNeedsDisplay]; } } - (BOOL)isTruncated { ASDN::MutexLocker l(__instanceLock__); ASTextKitRenderer *renderer = [self _renderer]; return renderer.firstVisibleRange.length < _attributedText.length; } - (void)setPointSizeScaleFactors:(NSArray *)pointSizeScaleFactors { ASDN::MutexLocker l(__instanceLock__); if ([_pointSizeScaleFactors isEqualToArray:pointSizeScaleFactors] == NO) { _pointSizeScaleFactors = pointSizeScaleFactors; [self _invalidateRenderer]; [self setNeedsDisplay]; }} - (void)setMaximumNumberOfLines:(NSUInteger)maximumNumberOfLines { ASDN::MutexLocker l(__instanceLock__); if (_maximumNumberOfLines != maximumNumberOfLines) { _maximumNumberOfLines = maximumNumberOfLines; [self _invalidateRenderer]; [self setNeedsDisplay]; } } - (NSUInteger)lineCount { ASDN::MutexLocker l(__instanceLock__); return [[self _renderer] lineCount]; } #pragma mark - Truncation Message - (void)_updateComposedTruncationText { ASDN::MutexLocker l(__instanceLock__); _composedTruncationText = [self _prepareTruncationStringForDrawing:[self _composedTruncationText]]; } - (void)_invalidateTruncationText { [self _updateComposedTruncationText]; [self _invalidateRenderer]; [self setNeedsDisplay]; } /** * @return the additional truncation message range within the as-rendered text. * Must be called from main thread */ - (NSRange)_additionalTruncationMessageRangeWithVisibleRange:(NSRange)visibleRange { ASDN::MutexLocker l(__instanceLock__); // Check if we even have an additional truncation message. if (!_additionalTruncationMessage) { return NSMakeRange(NSNotFound, 0); } // Character location of the unicode ellipsis (the first index after the visible range) NSInteger truncationTokenIndex = NSMaxRange(visibleRange); NSUInteger additionalTruncationMessageLength = _additionalTruncationMessage.length; // We get the location of the truncation token, then add the length of the // truncation attributed string +1 for the space between. return NSMakeRange(truncationTokenIndex + _truncationAttributedText.length + 1, additionalTruncationMessageLength); } /** * @return the truncation message for the string. If there are both an * additional truncation message and a truncation attributed string, they will * be properly composed. */ - (NSAttributedString *)_composedTruncationText { ASDN::MutexLocker l(__instanceLock__); //If we have neither return the default if (!_additionalTruncationMessage && !_truncationAttributedText) { return _composedTruncationText; } // Short circuit if we only have one or the other. if (!_additionalTruncationMessage) { return _truncationAttributedText; } if (!_truncationAttributedText) { return _additionalTruncationMessage; } // If we've reached this point, both _additionalTruncationMessage and // _truncationAttributedString are present. Compose them. NSMutableAttributedString *newComposedTruncationString = [[NSMutableAttributedString alloc] initWithAttributedString:_truncationAttributedText]; [newComposedTruncationString replaceCharactersInRange:NSMakeRange(newComposedTruncationString.length, 0) withString:@" "]; [newComposedTruncationString appendAttributedString:_additionalTruncationMessage]; return newComposedTruncationString; } /** * - cleanses it of core text attributes so TextKit doesn't crash * - Adds whole-string attributes so the truncation message matches the styling * of the body text */ - (NSAttributedString *)_prepareTruncationStringForDrawing:(NSAttributedString *)truncationString { ASDN::MutexLocker l(__instanceLock__); truncationString = ASCleanseAttributedStringOfCoreTextAttributes(truncationString); NSMutableAttributedString *truncationMutableString = [truncationString mutableCopy]; // Grab the attributes from the full string if (_attributedText.length > 0) { NSAttributedString *originalString = _attributedText; NSInteger originalStringLength = _attributedText.length; // Add any of the original string's attributes to the truncation string, // but don't overwrite any of the truncation string's attributes NSDictionary *originalStringAttributes = [originalString attributesAtIndex:originalStringLength-1 effectiveRange:NULL]; [truncationString enumerateAttributesInRange:NSMakeRange(0, truncationString.length) options:0 usingBlock: ^(NSDictionary *attributes, NSRange range, BOOL *stop) { NSMutableDictionary *futureTruncationAttributes = [NSMutableDictionary dictionaryWithDictionary:originalStringAttributes]; [futureTruncationAttributes addEntriesFromDictionary:attributes]; [truncationMutableString setAttributes:futureTruncationAttributes range:range]; }]; } return truncationMutableString; } @end @implementation ASTextNode (Deprecated) - (void)setAttributedString:(NSAttributedString *)attributedString { self.attributedText = attributedString; } - (NSAttributedString *)attributedString { return self.attributedText; } - (void)setTruncationAttributedString:(NSAttributedString *)truncationAttributedString { self.truncationAttributedText = truncationAttributedString; } - (NSAttributedString *)truncationAttributedString { return self.truncationAttributedText; } @end