NSGradient into NSColor

Question

OK, long story short:

• I'm using (embedded into the bundle) FontAwesome
• I'm using it as the font in some custom NSButtons
• In the NSButton subclass I want to colour them, exactly the way the Xcode tab items are coloured

This is how I'm setting the color (as a simple NSColor):

    NSColor *color = [NSColor colorWithCalibratedRed:0.09 green:0.55 blue:0.90 alpha:1.0];
    NSMutableAttributedString *colorTitle =
    [[NSMutableAttributedString alloc] initWithAttributedString:[self attributedTitle]];

    NSRange titleRange = NSMakeRange(0, [colorTitle length]);

    [colorTitle addAttribute:NSForegroundColorAttributeName
                       value:color
                       range:titleRange];

    [self setAttributedTitle:colorTitle];

How can I set it to an NSGradient?

Answer 1

OK, here's the solution, for anyone who may find useful...

Step 1:

Create a category on NSColor, based on the great answer by @Omz. In the code below, you'll see it renamed as colorFromGradient:, solely in order to mix well with the usual Cocoa naming conventions...

Step 2:

Redraw the title with the gradient color

    NSColor* gS = [NSColor colorWithCalibratedRed:0.07 green:0.47 blue:0.87 alpha:1.0];
    NSColor* gE = [NSColor colorWithCalibratedRed:0.12 green:0.64 blue:0.94 alpha:1.0];
    NSGradient* g = [[NSGradient alloc] initWithStartingColor:gE endingColor:gS];
    NSColor *color = [NSColor colorFromGradient:g];

    NSMutableAttributedString *colorTitle =
    [[NSMutableAttributedString alloc] initWithAttributedString:[self attributedTitle]];

    NSRange titleRange = NSMakeRange(0, [colorTitle length]);

    [colorTitle addAttribute:NSForegroundColorAttributeName
                       value:color
                       range:titleRange];

    [self setAttributedTitle:colorTitle];

Step 3:

Enjoy the result. :-)