xcode 错误：使用未解析的标识符“kCGBlendModeMultiply”
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Error: Use of unresolved identifier 'kCGBlendModeMultiply'
提问by MLyck
I recently updated to Xcode 7, beta 3.
我最近更新到 Xcode 7, beta 3。
And I've run into some issues, I can't seem to find any questions for on SO.
我遇到了一些问题，我似乎找不到关于 SO 的任何问题。
When I run my application, i get 3 errors:
当我运行我的应用程序时，我收到 3 个错误：
Use of unresolved identifier 'kCGBlendModeMultiply'
Use of unresolved identifier 'kCGLineCapRound'
Use of unresolved identifier 'kCGLineJoinMiter'
使用未解析的标识符“kCGBlendModeMultiply”
使用未解析的标识符“kCGLineCapRound”
使用未解析的标识符“kCGLineJoinMiter”
However the 2 latter ones, disappear, although I assume they will show up after the first one is fixed (hence why I included it in this question).
然而，后两个消失了，尽管我认为它们会在第一个修复后出现（因此我将它包含在这个问题中）。
I didn't see anything in the release notes about these being removed? So I'm a bit stuck at what to do. I tried rewriting the lines of course, but the 3 things I used don't show up as options anymore. In case that they are just gone in the latest Swift 2.0, what can I use instead?
我在发行说明中没有看到关于这些被删除的任何内容？所以我有点不知道该怎么做。我当然尝试重写这些行，但是我使用的 3 件事不再显示为选项。如果它们在最新的 Swift 2.0 中消失了，我可以用什么代替？
Here's the code for the first error.
这是第一个错误的代码。
func alpha(value:CGFloat)->UIImage
{
UIGraphicsBeginImageContextWithOptions(self.size, false, 0.0)
let ctx = UIGraphicsGetCurrentContext()
let area = CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height)
CGContextScaleCTM(ctx, 1, -1);
CGContextTranslateCTM(ctx, 0, -area.size.height)
CGContextSetBlendMode(ctx, kCGBlendModeMultiply)
CGContextSetAlpha(ctx, value)
CGContextDrawImage(ctx, area, self.CGImage)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage;
}
Here's the code for the 2 latter errors:
这是后两个错误的代码：
for layer in [ self.top, self.middle, self.bottom ] {
layer.fillColor = nil
layer.strokeColor = UIColor.whiteColor().CGColor
layer.lineWidth = 4
layer.miterLimit = 4
layer.lineCap = kCALineCapRound
layer.masksToBounds = true
let strokingPath = CGPathCreateCopyByStrokingPath(layer.path, nil, 4, kCGLineCapRound, kCGLineJoinMiter, 4)
layer.bounds = CGPathGetPathBoundingBox(strokingPath)
layer.actions = [
"strokeStart": NSNull(),
"strokeEnd": NSNull(),
"transform": NSNull()
]
self.layer.addSublayer(layer)
}
Any help would be greatly appreciated! :)
任何帮助将不胜感激！:)
回答by courteouselk
This should work:
这应该有效：
CGContextSetBlendMode(ctx, CGBlendMode.Multiply)
... or even just this:
......甚至只是这个：
CGContextSetBlendMode(ctx, .Multiply)
If you Ctrl-clickon CGContextSetBlendModeand then from its declaration jump (in the same way) to declaration of CGBlendModethen you will see:
如果你Ctrl-click在CGContextSetBlendMode，然后从它的声明跳跃（以同样的方式）来的声明CGBlendMode，那么你将看到：
enum CGBlendMode : Int32 {
/* Available in Mac OS X 10.4 & later. */
case Normal
case Multiply
case Screen
case Overlay
// ...
}
Similarly, the other line that produces the error should be changed to:
同样，产生错误的另一行应更改为：
let strokingPath = CGPathCreateCopyByStrokingPath(layer.path, nil, 4, .Round, .Miter, 4)
