[UPDATED]我正在尝试为PDFView设置pageOverlayViewProvider，但它无法按预期工作。未调用PDFPageOverlayViewProvider方法，PDFViewDelegate方法工作正常。
struct ReaderView: UIViewRepresentable {
public typealias UIViewType = PDFView
let url: URL
let document: PDFDocument
init(_ url: URL) {
self.url = url
self.document = PDFDocument(url: self.url)!
}
func makeCoordinator() -> Coordinator {
Coordinator()
}
func makeUIView(context: Context) -> PDFView {
let pdfView = PDFView()
pdfView.document = document
pdfView.displayMode = .singlePageContinuous
pdfView.displayDirection = .vertical
pdfView.autoScales = true
pdfView.delegate = context.coordinator
pdfView.pageOverlayViewProvider = context.coordinator
pdfView.usePageViewController(true)
pdfView.backgroundColor = .clear
document.delegate = context.coordinator
return pdfView
}
func updateUIView(_ uiView: PDFView, context: Context) {
}
}
extension ReaderView {
class Coordinator: NSObject, PDFPageOverlayViewProvider, PDFViewDelegate, PDFDocumentDelegate {
func pdfView(_ view: PDFView, overlayViewFor page: PDFPage) -> UIView? {
return UIView(frame: .zero)
}
func pdfView(_ pdfView: PDFView, willDisplayOverlayView overlayView: UIView, for page: PDFPage) {
}
func pdfView(_ pdfView: PDFView, willEndDisplayingOverlayView overlayView: UIView, for page: PDFPage) {
}
func pdfViewWillClick(onLink sender: PDFView, with url: URL) {
}
func didMatchString(_ instance: PDFSelection) {
}
}
要使pageOverlayViewProvider与PDFView协同工作，似乎必须在将PDF文档与PDFView关联之前设置此实例属性。
在使用UIViewRepresentable时，当使用makeUIView功能制作PDFView时，以下内容应该有效：
func makeUIView(context: Context) -> PDFView {
let pdfView = PDFView()
pdfView.displayMode = .singlePageContinuous
pdfView.displayDirection = .vertical
pdfView.autoScales = true
pdfView.delegate = context.coordinator
pdfView.pageOverlayViewProvider = context.coordinator
pdfView.usePageViewController(true)
pdfView.backgroundColor = .clear
pdfView.document = document
document.delegate = context.coordinator
return pdfView
}