Question

我正在尝试将文本渲染为不是矩形的形状。添加矩形路径时，以下代码有效，但添加椭圆路径时则无效。最终，我想画任何路径（L形等），有没有人对此有任何好运？

-(void)drawRect:(CGRect)rect {
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetTextMatrix(context, CGAffineTransformIdentity);

    CGMutablePathRef path = CGPathCreateMutable();
    float w = 200.0;
    float h = 300.0;
    CGRect bounds = CGRectMake(10.0, 10.0, w, h);

    // I draw using only one of the following lines
    CGPathAddRect(path, NULL, bounds); // THIS LINE WILL WORK
    //CGPathAddEllipseInRect(path, NULL, bounds); // THIS LINE WILL CRASH IT


    // Initialize an attributed string.
    CFStringRef string = CFSTR("Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.");
    CFMutableAttributedStringRef attrString = CFAttributedStringCreateMutable(kCFAllocatorDefault, 0);
    CFAttributedStringReplaceString (attrString, CFRangeMake(0, 0), string);

    // Create the framesetter with the attributed string.
    CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(attrString); 
    CFRelease(attrString);

    // Create the frame and draw it into the graphics context
    CTFrameRef frame = CTFramesetterCreateFrame(framesetter, CFRangeMake(0, 0), path, NULL);

    // Flip the text
    CGAffineTransform flip = CGAffineTransformMake(1.0, 0.0, 0.0, -1.0, 0, self.frame.size.height);
    CGContextConcatCTM(context, flip);

    CTFrameDraw(frame, context);
    CFRelease(framesetter);
    CFRelease(frame);
}

非常感谢任何帮助或想法。我很难过。

Answer 1

http://lists.apple.com/archives/quartz-dev/2010/Mar/msg00049.html

问题是文档错误。该功能当前不支持非矩形路径。我希望它能尽快实施，但现在还没有。

Answer 2

你可以在任何类型的UIBezierPath上绘制，示例代码如下： https://github.com/erica/iOS-5-Cookbook/tree/master/C10/19-Drawing%20onto%20Paths

核心文本：渲染为奇怪的形状

2 个答案: