我想从MKMarkerAnnotationView获取UIImage但是使用以下代码截断图像(在顶部和底部,请参见屏幕截图)
let newAnnotation = SimpleAnnotation(sourceCoordinate: annotation.coordinate, sourceTitle: "Hello", sourceSubtitle: "world")
let pinAnnotation = MKMarkerAnnotationView(annotation: newAnnotation, reuseIdentifier: "Test")
pinAnnotation.markerTintColor = UIColor.red
pinAnnotation.glyphText = "1"
pinAnnotation.animatesWhenAdded = false
pinAnnotation.glyphTintColor = UIColor.white
pinAnnotation.titleVisibility = .hidden
pinAnnotation.subtitleVisibility = .hidden
UIGraphicsBeginImageContextWithOptions(pinAnnotation.bounds.size, false, 0.0)
pinAnnotation.drawHierarchy(in: CGRect(x:0,
y:0,
width:pinAnnotation.bounds.width,
height:pinAnnotation.bounds.height),
afterScreenUpdates: true)
let snapshotImageFromMyView = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
知道它被截断的原因吗?在Xcode调试器中,我可以看到图像已经在pinAnnotation中被截断了(在我使用UIGraphics之前...来获取UIImage)
答案 0 :(得分:0)
我找到了解决方案!我只需要将contentMode设置为scaleAspectFit并将边界更改为我需要的图像大小(40x40px)。
这里是显示完整MKMarkerAnnotationView的代码。
let pinAnnotation = MKMarkerAnnotationView()
pinAnnotation.markerTintColor = UIColor.red
pinAnnotation.glyphText = "1"
pinAnnotation.animatesWhenAdded = false
pinAnnotation.glyphTintColor = UIColor.white
pinAnnotation.titleVisibility = .hidden
pinAnnotation.subtitleVisibility = .hidden
pinAnnotation.contentMode = .scaleAspectFit
pinAnnotation.bounds = CGRect(x: 0, y: 0, width: 40, height: 40)
UIGraphicsBeginImageContextWithOptions(pinAnnotation.bounds.size, false, 0.0)
pinAnnotation.drawHierarchy(in: CGRect(x:0,
y:0,
width:pinAnnotation.bounds.width,
height:pinAnnotation.bounds.height),
afterScreenUpdates: true)
let snapshotImageFromMyView = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
此页面Demystifying iOS Layout帮助我找到了这个解决方案。
答案 1 :(得分:0)
我无法使drawHierarchy工作,我只是回到空图像。