如何在swift中为path设置fillColor和strokColor
如何在swift中为path设置fillColor和strokColor
提问于 2019-06-21 03:04:11
我正在使用MKMapSnapshotter获取特定区域的图像。
我使用UIGraphicsGetCurrentContext()在图像上绘制线条以显示多边形，
我可以设置线条的颜色，但是我不能设置多边形的填充颜色。
下面是代码
private func drawLineOnImage(snapshot: MKMapSnapshotter.Snapshot, coordinates: [CLLocationCoordinate2D]) -> UIImage {
let image = snapshot.image
UIGraphicsBeginImageContextWithOptions(getMapFrameSize(), true, 0)
image.draw(at: CGPoint.zero)
let context = UIGraphicsGetCurrentContext()
context!.setLineWidth(2.0)
context!.setStrokeColor(UIColor.red.cgColor)
context!.move(to: snapshot.point(for: coordinates[0]))
for i in 0...coordinates.count-1 {
context!.addLine(to: snapshot.point(for: coordinates[i]))
context!.move(to: snapshot.point(for: coordinates[i]))
}
context!.strokePath()
context!.setFillColor(UIColor.green.cgColor)
context!.fillPath()
let resultImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return resultImage!
}我如何才能做到这一点？
解决方案：
private func drawLineOnImage(snapshot: MKMapSnapshotter.Snapshot, coordinates: [CLLocationCoordinate2D]) -> UIImage {
let image = snapshot.image
UIGraphicsBeginImageContextWithOptions(getMapFrameSize(), true, 0)
image.draw(at: CGPoint.zero)
let context = UIGraphicsGetCurrentContext()!
context.setLineWidth(2.0)
context.setStrokeColor(annotationColor.cgColor)
context.setFillColor(annotationColor.withAlphaComponent(0.5).cgColor)
var coordinates = coordinates
if let firstPoint = coordinates.first { context.move(to: snapshot.point(for: firstPoint)) }
context.move(to: snapshot.point(for: coordinates[0]))
coordinates.removeFirst()
coordinates.forEach { context.addLine(to: snapshot.point(for: $0)) }
context.drawPath(using: .fillStroke)
context.fillPath()
let resultImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return resultImage!
}回答 1
Stack Overflow用户
回答已采纳
发布于 2019-06-21 03:18:56
来自strokePath和fillPath的文档
作为调用此函数的副作用，当前路径将被清除。
这意味着在调用strokePath之后，路径将被清除，因此在调用fillPath时不需要绘制任何内容
相反，应该调用context!.drawPath(using: .fillStroke)
页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：
https://stackoverflow.com/questions/56692375
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