core-text

问题 I am implementing a customized rich text editor by extending the UITextView. When user selects the text range and apples the 'highlighting' menu, the editor will draw a blue background for the selected text: - (CGRect)getRectAtRangePos:(NSInteger)pos { UITextPosition *beginning = self.beginningOfDocument; UITextPosition *start = [self positionFromPosition:beginning offset:pos]; CGRect rect = [self caretRectForPosition:start]; return [self convertRect:rect fromView:self.textInputView]; } -

问题 I've a CTFontRef variable. CTFontRef aFontRef; Getting Size of Font was easy : CGFloat aFontSize = CTFontGetSize(aFontRef); Please help me in retrieving the FontName. I'm expecting the FontName to be something like MarkerFelt-Wide . But, when I use methods like CTFontCopyFullName(aFontRef) I get Marker Felt Wide Cheers Roshit 回答1: Looks like you want the PostScript name, which you can obtain through CTFontCopyPostScriptName(). The PostScript name is an internal name, and is generally the

问题 I have a problem changing substring color using "NSForegroundColorAttributeName". I'm confused since other attributes for the same substring are being applied(underline). Also tried to use deprecated attribute "UITextAttributeTextColor" and other suggested attribute "kCTForegroundColorAttributeName" and got the same effect. I'm compiling for iOS 7. NSString *freeText = [NSString stringWithFormat:@"(%@)", self.me.activity.text]; int lblMaxWidth = arrImgView.origin.x - WPRConstraints

问题 I'm working on coretext in iOS. I have implemented a custom UIView by replacing -drawRect method with the following code: - (void)drawRect:(CGRect)rect { [super drawRect:rect]; CGRect frameRect=CGRectMake(50, 200, 80, 15); // NSString *textToDraw=@"A-BCDEFGHIJKLM"; // NSString *textToDraw=@"abc"; // NSString *textToDraw=@"ABCDEFGHIJKLMNOPQRST"; NSString *textToDraw=@"A-BCDEFGHIJ"; // NSString *textToDraw=@"A-BCDEFGHI"; CFStringRef stringRef = (__bridge CFStringRef)textToDraw;

问题 I need to draw text on a background thread to save it as an image. I'm doing UIGraphicsPushContext() [NSString drawInRect:] UIGraphicsPopContext() The code works fine, but sometimes it crashes in drawInRect when I'm also drawing on the main thread at the same time. I tried to use NSAttributedString as suggested here: UIStringDrawing methods don't seem to be thread safe in iOS 6. But [NSAttributedString drawInRect:] doesn't seem to render anything on my background thread for some reason. Main

问题 I am looking into making an app where a user can change the size and orientation of UITextField . I was looking into Aviary app and what I see is that users can not only increase or decrease the size of the text but they can also change its orientation. So the questions I want to ask are 1) Are they using CoreText to do this are they using just plain old UILabel or UIText ? 2) I don't know how you can dynamically resize? Are they using UIView ? 3) I have googled CoreText tutorials, examples,

问题 Trying to display super/subscript text using NSAttributedString in a UITextView seems broken in iOS13 - unless anyone knows otherwise? Curiously if I use the UIFont systemFont then it works - but if I use any other font it doesn't. See below for my code to setup a UITextView in my test app. - (void)viewDidLoad { [super viewDidLoad]; UIFont* font = [UIFont systemFontOfSize:32]; //UIFont* font = [UIFont fontWithName:@"Helvetica Neue" size:32]; //UIFont* font = [UIFont fontWithName:@"Courier"

问题 I have a UILabel whose property text I would like to set paragraphs of text to using NSString . I have an array in which I store a sequence of characters that represent a text paragraph. The paragraph doesn't have to fit/included perfectly within this UILabel . If the paragraph doesn't end, I would move on to the next label. Let say if I had rect size of this UILabel 160 X 240, how could I be able to determine the correct font size in order to fill this string of the UILabel within nicely? Is

问题 Is it possible to align multiple sized text by bounding center (of each size) instead of baseline? I tried CTRunDelegate feature, but it doesn't work. It was possible with CTRunDelegateCallbacks.getAscent and CTRunDelegateCallbacks.getDescent , but the feature doesn't work. Only CTRunDelegateCallbacks.getWidth worked. I succeed to laying out multiple sized text, images, and any objects, but only baseline-alignment supported. 回答1: The run delegate methods getAscent and getDescent are, in fact,

问题 According to the docs, CTFramesetterSuggestFrameSizeWithConstraints () "determines the frame size needed for a string range". Unfortunately the size returned by this function is never accurate. Here is what I am doing: NSAttributedString *string = [[[NSAttributedString alloc] initWithString:@"lorem ipsum" attributes:nil] autorelease]; CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef) string); CGSize textSize =