ios 如何从 RGB 值中获取 cgcolor？
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how can i obtain a cgcolor from RGB values?
提问by alionthego
I'm trying to create a custom RGBCGColorusing swiftto use as a border color for a UIButton. I've tried following code but the color is not visible:
我试图创建一个自定义RGBCGColor使用swift的边框颜色的使用UIButton。我试过下面的代码，但颜色不可见：
var red = UIColor(red: 100.0, green: 130.0, blue: 230.0, alpha: 1.0)
self.layer.borderColor = red.CGColor
Is there any way to create a CGColordirectly from RGB values?
有没有办法CGColor直接从RGB值创建一个？
回答by Shruti
You have to give the values between 0 and 1.0. So divide the RGB values by 255.
您必须给出介于 0 和 1.0 之间的值。因此，将 RGB 值除以 255。
Change Your code to
将您的代码更改为
var red = UIColor(red: 100.0/255.0, green: 130.0/255.0, blue: 230.0/255.0, alpha: 1.0)
self.layer.borderColor = red.CGColor
回答by Mick Stupp
You can get that down to one line in Swift 3:
您可以在 Swift 3 中将其缩减为一行：
avLayer.backgroundColor = UIColor.red.CGColor
回答by Romain
On Mac OS X there is CGColorCreateGenericRGB(), but it doesn't exist on iOS. You can use CGColorCreatewith appropriate parameters, though.
在 Mac OS X 上有CGColorCreateGenericRGB()，但在 iOS 上不存在。不过，您可以使用CGColorCreate适当的参数。
self.layer.borderColor = CGColorCreate(CGColorSpaceCreateDeviceRGB(), [1.0, 0.5, 0.5, 1.0])
The values in the array are, in order of appearance: red, green, blue, and alpha. Just like UIColor:)
数组中的值按出现顺序为：红色、绿色、蓝色和 alpha。就像UIColor:)
回答by Usharao
UImage *newImage = [self imageWithColor:[UIColor colorWithRed:200/255. green:228/255. blue:194/255. alpha:0.99]];
回答by Matteo Piombo
Maybe all you need is set the borderWidth, by default it is 0, so it is not visible:
也许您只需要设置borderWidth，默认情况下它是 0，所以它不可见：
self.layer.borderWidth = 1.0
Just in case you can set the cornerRadiusif you need it rounded ... might be useful ;-)
以防万一你可以设置cornerRadius如果你需要它四舍五入......可能会有用;-)
self.layer.cornerRadius = 4.0
