iOS 8 - UILabel with gradient-colored text

Question

I'm trying to create a UILabel where the text is colored with a gradient. The gradient is dynamic, so I can't use a static image to do it. Further, every answer I've found uses some CGContext methods that have been deprecated (CGContextShowText in particular). The deprecation notes for these methods say "Use Core Text instead". However, I'm not all that familiar with Core Text, and I haven't been able to find any ways to do it through more searching. Does anybody know of a way to do this in iOS 8? Thanks!

Answer 1

I'm going to suggest a "workaround", namely, you can create a UIColor with an image, and an image can be created dynamically using any of the number of libraries out there.

The code for creating a gradient image would roughly be as follows (can probably be optimised to some extent):

CGSize size = CGSizeZero; // You should provide this yourself, height is important, width can be limited, for example 3

UIGraphicsBeginImageContextWithOptions(size, NO, 0);

// Assumes fromColor and toColor are UIColors passed into this context
NSArray *colors = @[(id)[fromColor CGColor], (id)[toColor CGColor]];
CGFloat positions[2] = {0.f, 1.f};
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGGradientRef gradient = CGGradientCreateWithColors(colorSpace, colors, positions);
CGColorSpaceRelease(colorSpace);

CGContextDrawLinearGradient(ctx, gradient, CGPointMake(0.f, 0.f), CGPointMake(0.f, size.height), kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
CGGradientRelease(gradient);

UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

// image contains the linear gradient image you need
UIColor *color = [UIColor colorWithPatternImage:image];
// Simply assign this color to be the textColor of the label