How to detect the orientation of a PDF page in Swift with PDFKit IOS - ios

Question

I'm trying to get the orientation property of a PDF document. The purpose is, I would like to add a button widget in a location that depends on the orientation of the PDF document.
For example:
func openPDFDocument() {
if let documentURL = Bundle.main.url(forResource: "PDF document", withExtension: "pdf"),
let document = PDFDocument(url: documentURL),
let page = document.page(at: 0) {
// Set our document to the view, center it, and set a background color
pdfView?.document = document
pdfView?.autoScales = true
pdfView?.backgroundColor = UIColor.lightGray
//I think I should be able to add a code here like:
if page.orientation = Horizontal {
self.insertResetButtonInto(page)
} else {
//do nothing or do something else
}
}
}
This is the function I would like to add in case the document is in Landscape mode:
func insertResetButtonInto(_ page: PDFPage) {
let pageBounds = page.bounds(for: .cropBox)
let resetButtonBounds = CGRect(x: 90, y: pageBounds.size.height - 300, width: 106, height: 32)
let resetButton = PDFAnnotation(bounds: resetButtonBounds, forType: PDFAnnotationSubtype(rawValue: PDFAnnotationSubtype.widget.rawValue), withProperties: nil)
resetButton.widgetFieldType = PDFAnnotationWidgetSubtype(rawValue: PDFAnnotationWidgetSubtype.button.rawValue)
resetButton.widgetControlType = .pushButtonControl
resetButton.caption = "Reset"
page.addAnnotation(resetButton)
// Create PDFActionResetForm action to clear form fields.
let resetFormAction = PDFActionResetForm()
resetFormAction.fieldsIncludedAreCleared = false
resetButton.action = resetFormAction
}
I got the example project from Apple's documentation website. I looked at a previous similar question, however it seems this was in Objective C.
I would appreciate the help in this matter.

Answer 1

There is no direct API to get the orientation from a PDFPage. But you can first get the page size from .mediaBox, then calculate the orientation like below.
let pageSize = page.bounds(for: .mediaBox).size
if pageSize.width > pageSize.height {
//landscape
} else {
//portrait
}

Answer 2

I use another way to get the orientation of my pdf page.
func IsLandscape(page: PDFPage) -> Bool {
let pointZero = pdfView.convert(CGPoint(x: 0, y: 0), from: page)
let pointTen = pdfView.convert(CGPoint(x: 10, y: 10), from: page)
let caculate = pointTen.x - pointZero.x
print("pointZero: \(pointZero), pointTen:\(pointTen)")
if (caculate > 0) {
print("landscape")
return true
}
else {
print("portrait")
return false
}
}