用户界面颜色getHue:饱和:亮度:α:没有回报-UIColorgetHue:saturation:brightness:alpha:returnsNO

I am using the following function to "change" the saturation, brightness and alpha of a UIColor:

我正在使用以下函数来“改变”UIColor的饱和度、亮度和alpha:

//UIColor *color = [self color:[UIColor redColor] saturation:0.5 brightness:0.5 alpha:0.5];

- (UIColor *)color:(UIColor *)color saturation:(CGFloat)saturation brightness:(CGFloat)brightness alpha:(CGFloat)alpha {
    CGFloat h, s, b, a;
    [color getHue:&h saturation:&s brightness:&b alpha:&a];
    return [UIColor colorWithHue:h saturation:(s * saturation) brightness:(b * brightness) alpha:(a * alpha)];
}

Prior to iOS 11 (GM) this was working perfectly fine. However, now [UIColor getHue:saturation:brightness:alpha:] returns NO and the hsba values aren't getting changed.

在ios11 (GM)之前，运行得非常好。然而，现在[UIColor getHue::bright:alpha:]返回NO, hsba值不会改变。

Comment in UIColor.h says:

在用户界面颜色发表评论。h说:

If the receiver is of a compatible color space, any non-NULL parameters are populated and 'YES' is returned. Otherwise, the parameters are left unchanged and 'NO' is returned.

如果接收器是兼容的颜色空间，则会填充任何非空参数，并返回“YES”。否则，参数将保持不变并返回'NO'。

What does "compatible color space" mean here? Do I have to convert color spaces? How do I accomplish that? All the colors in my .xcassets are in sRGB.

“兼容颜色空间”在这里是什么意思?我需要转换颜色空间吗?我怎么做到的?我的.xcassets中的所有颜色都在sRGB中。

EDIT: Kind of a fix is to use the following way to get the HSBA values:

编辑:一种修复方法是使用以下方法获取HSBA值:

CGFloat rTemp, gTemp, bTemp, aTemp;
[color getRed:&rTemp green:&gTemp blue:&bTemp alpha:&aTemp];
CGFloat h, s, b, a;
[[UIColor colorWithRed:rTemp green:gTemp blue:bTemp alpha:aTemp] getHue:&h saturation:&s brightness:&b alpha:&a];

1 个解决方案

if let cs = CGColorSpace(name: CGColorSpace.sRGB) {
    if let cc = CGColor(colorSpace: cs, components: [0.5, 0.7, 0.3, 1.0]) {
        let color = UIColor(cgColor: cc)
        print(color)
        var h: CGFloat = 0
        var s: CGFloat = 0
        var b: CGFloat = 0
        if color.getHue(&h, saturation: &s, brightness: &b, alpha: nil) {
            print(h, s, b)
        } else {
            print("Failed with color space \(cs)")
        }
    }
}