将PDFAnnotationSubtype等于.widget的PDFAnnotation在将其添加到PDFPage后不会刷新其外观

将注释添加到PDFPage(并在屏幕上呈现)后,无法在PDFPage/ 上更新其外观PDFView.

重现问题:

创建PDFAnnotation并将其添加到PDFPage:

let bounds = CGRect(x: 20.0, y: 20.0, width: 200.0, height: 200.0)
let annotation = PDFAnnotation(bounds: b, forType: .widget, withProperties: nil)
annotation.widgetFieldType = .text
annotation.backgroundColor = .gray
annotation.fOnt= .systemFont(ofSize: 18)
annotation.widgetStringValue = "Test!"

page.addAnnotation(annotation)

在PDFPage上显示后,尝试编辑其边界/颜色/背景颜色/字符串值等:

annotation?.setValue("Help! SOS! Mayday!", forAnnotationKey: .widgetValue)
annotation?.color = .green
annotation?.bounds = CGRect(x: 0.0, y: 0.0, width: 100.0, height: 100.0)

什么都没发生.

我知道一个诀窍:

    page.removeAnnotation(annotation)
    page.addAnnotation(annotation)

但这是一种解决方法,而不是真正的解决方案.