我有兴趣在CoreText中创建一个尽可能多地表现UILabel行为的方法。因此，如果我希望实现类似的目标：
UIFont *font1 = [UIFont fontWithName:kMyriadProSemiBold size:15];
NSDictionary *arialDict = [NSDictionary dictionaryWithObject: font1 forKey:NSFontAttributeName];
NSMutableAttributedString *aAttrString1 = [[NSMutableAttributedString alloc] initWithString:@"My" attributes: arialDict];
UIFont *font2 = [UIFont fontWithName:kMyriadProRegular size:15];
NSDictionary *arialDict2 = [NSDictionary dictionaryWithObject: font2 forKey:NSFontAttributeName];
NSMutableAttributedString *aAttrString2 = [[NSMutableAttributedString alloc] initWithString:@"Profile" attributes: arialDict2];
[aAttrString1 appendAttributedString:aAttrString2];
但是使用Core Text。
目前我正在使用下一个方法：
+ (void)drawText:(NSString *)textToDraw
inFrame:(CGRect)frameRect
withFont:(UIFont *)originalFont
textColor:(UIColor *)textColor
alignment:(PDFTextAlignment)alignment{
if (!textToDraw) {
// If nil, give it an empty value to draw
textToDraw = @"";
}
// Prepare font
CTFontRef font = [PDFManager ctFontRefFromUIFont:originalFont];
CGColorRef color = textColor.CGColor;
// Paragraph
CTTextAlignment ctAlignment;
switch (alignment) {
case PDFTextAlignmentLeft:
ctAlignment = kCTTextAlignmentLeft;
break;
case PDFTextAlignmentCenter:
ctAlignment = kCTTextAlignmentCenter;
break;
case PDFTextAlignmentRight:
ctAlignment = kCTTextAlignmentRight;
break;
case PDFTextAlignmentJustified:
ctAlignment = kCTTextAlignmentJustified;
break;
default:
ctAlignment = kCTTextAlignmentLeft;
break;
}
CTParagraphStyleSetting settings[] = {
{kCTParagraphStyleSpecifierAlignment, sizeof(ctAlignment), &ctAlignment},
};
CTParagraphStyleRef paragraphStyle = CTParagraphStyleCreate(settings, sizeof(settings) / sizeof(settings[0]));
// Create an attributed string
CFStringRef keys[] = { kCTFontAttributeName, kCTForegroundColorAttributeName, kCTParagraphStyleAttributeName };
CFTypeRef values[] = { font, color, paragraphStyle };
CFDictionaryRef attr = CFDictionaryCreate(NULL, (const void **)&keys, (const void **)&values,
sizeof(keys) / sizeof(keys[0]), &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
CFStringRef stringRef = (__bridge CFStringRef)textToDraw;
// Prepare the text using a Core Text Framesetter.
CFAttributedStringRef currentText = CFAttributedStringCreate(NULL, stringRef, attr);
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(currentText);
CGMutablePathRef framePath = CGPathCreateMutable();
CGPathAddRect(framePath, NULL, frameRect);
// Get the frame that will do the rendering.
CFRange currentRange = CFRangeMake(0, 0);
CTFrameRef frameRef = CTFramesetterCreateFrame(framesetter, currentRange, framePath, NULL);
CGPathRelease(framePath);
// Get the graphics context.
CGContextRef currentContext = UIGraphicsGetCurrentContext();
// Put the text matrix into a known state. This ensures
// that no old scaling factors are left in place.
CGContextSetTextMatrix(currentContext, CGAffineTransformIdentity);
// Core Text draws from the bottom-left corner up, so flip
// the current transform prior to drawing.
// Modify this to take into consideration the origin.
CGContextTranslateCTM(currentContext, 0, frameRect.origin.y*2);
CGContextScaleCTM(currentContext, 1.0, -1.0);
// Draw the frame.
CTFrameDraw(frameRef, currentContext);
// Add these two lines to reverse the earlier transformation.
CGContextScaleCTM(currentContext, 1.0, -1.0);
CGContextTranslateCTM(currentContext, 0, (-1)*frameRect.origin.y*2);
//Confirm that everything is released that needs to be!
CFRelease(frameRef);
CFRelease(stringRef);
CFRelease(framesetter);
CFRelease(font);
CFRelease(paragraphStyle);
}
我需要更新CFDictionaryRef attr才能接受新属性吗？
答案 0 :(得分：0)
我最终实际使用NSAttributedString作为fallows并将方法从上面转换为：
+ (void)drawAttributedText:(NSAttributedString *)textToDraw
inFrame:(CGRect)frameRect
alignment:(PDFTextAlignment)alignment{
// Paragraph
CTTextAlignment ctAlignment;
switch (alignment) {
case PDFTextAlignmentLeft:
ctAlignment = kCTTextAlignmentLeft;
break;
case PDFTextAlignmentCenter:
ctAlignment = kCTTextAlignmentCenter;
break;
case PDFTextAlignmentRight:
ctAlignment = kCTTextAlignmentRight;
break;
case PDFTextAlignmentJustified:
ctAlignment = kCTTextAlignmentJustified;
break;
default:
ctAlignment = kCTTextAlignmentLeft;
break;
}
CTParagraphStyleSetting settings[] = {
{kCTParagraphStyleSpecifierAlignment, sizeof(ctAlignment), &ctAlignment},
};
CTParagraphStyleRef paragraphStyle = CTParagraphStyleCreate(settings, sizeof(settings) / sizeof(settings[0]));
CFAttributedStringRef currentText = (__bridge CFAttributedStringRef)textToDraw;
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(currentText);
CGMutablePathRef framePath = CGPathCreateMutable();
CGPathAddRect(framePath, NULL, frameRect);
// Get the frame that will do the rendering.
CFRange currentRange = CFRangeMake(0, 0);
CTFrameRef frameRef = CTFramesetterCreateFrame(framesetter, currentRange, framePath, NULL);
CGPathRelease(framePath);
// Get the graphics context.
CGContextRef currentContext = UIGraphicsGetCurrentContext();
// Put the text matrix into a known state. This ensures
// that no old scaling factors are left in place.
CGContextSetTextMatrix(currentContext, CGAffineTransformIdentity);
// Core Text draws from the bottom-left corner up, so flip
// the current transform prior to drawing.
// Modify this to take into consideration the origin.
CGContextTranslateCTM(currentContext, 0, frameRect.origin.y*2);
CGContextScaleCTM(currentContext, 1.0, -1.0);
// Draw the frame.
CTFrameDraw(frameRef, currentContext);
// Add these two lines to reverse the earlier transformation.
CGContextScaleCTM(currentContext, 1.0, -1.0);
CGContextTranslateCTM(currentContext, 0, (-1)*frameRect.origin.y*2);
//Confirm that everything is released that needs to be!
CFRelease(frameRef);
CFRelease(framesetter);
CFRelease(paragraphStyle);
}
+ (NSMutableAttributedString *)getAttributedString:(NSString *)str
withFont:(UIFont *)font
andColor:(UIColor *)fontColor{
NSDictionary *arialDict = [NSDictionary dictionaryWithObject: font forKey:NSFontAttributeName];
NSMutableAttributedString *attrString = [[NSMutableAttributedString alloc] initWithString:str attributes: arialDict];
return attrString;
}
以及使用它的方式是：
+ (void)drawPDFTitleUsingString:(NSString *)passedTitle{
NSMutableAttributedString *attStr1 = [self getAttributedString:NSLocalizedString(@"Normal part of the string, ", nil)
withFont:FONT_CLEAR_SANS_REGULAR(18)
andColor:[UIColor blackColor]];
NSMutableAttributedString *attStr2 = [self getAttributedString:NSLocalizedString(@"bold part of the string", nil)
withFont:FONT_CLEAR_SANS_BOLD(18)
andColor:[UIColor blackColor]];
[attStr1 appendAttributedString:attStr2];
[self drawAttributedText:attStr1
inFrame:CGRectMake(PDFTableXPosition, 15 + 55, PDFTableWidth, 42)
alignment:PDFTextAlignmentLeft];
}