Resize and Rotate image Annotation added in pdf - ios

Question

Using this Link I have added signature image annotation in PDF file
But i could not find any guide for how to rotate and resize image annotation using the button added on top of annotation image like shown in the image.
What i want to do is:
want to scale/resize signature image(make it small or large by adding this resize button)
want to rotate signature image
For Pinch to zoom i am adding pinch gesture to PDFView but that gesture zoom in / zoom out the main pdf.tried to fix it by below code but not worked.
#objc func scale(sender : UIPinchGestureRecognizer) {
print("----------Scale----------")
let touchLocation = sender.location(in: pdfContainerView)
guard let page = pdfContainerView.page(for: touchLocation, nearest: true)
else {
return
}
let locationOnPage = pdfContainerView.convert(touchLocation, to: page)
switch sender.state {
case .began:
guard let annotation = page.annotation(at: locationOnPage) else {
return
}
if annotation.isKind(of: ImageStampAnnotation.self) {
currentlySelectedAnnotation = annotation
// to disable pinch gesture for pdfview but it is not working
pdfContainerView.minScaleFactor = pdfContainerView.scaleFactor
pdfContainerView.maxScaleFactor = pdfContainerView.scaleFactor
}
case .changed,.ended:
guard let annotation = currentlySelectedAnnotation else {
return
}
let initialBounds = annotation.bounds
//scale annotation
case .cancelled:
break
default:
break
}
}
Thanks in advance!!

Answer 1

I tried to implement rotation, zoom, pan on PDFview.
I created a new view above the PDFAnnotation and then moved, rotated, and scaled the view as above.
about PDFAnnotation:
class PDFImageAnnotation: PDFAnnotation {
let image: UIImage
let originalBounds: CGRect
/// 0 - 360
var angle: CGFloat = 0 {
didSet {
// reload annotation
shouldDisplay = true
}
}
/// scale annotation
var scale: CGFloat = 1 {
didSet {
// Scale on the original size
let width = originalBounds.width * scale
let height = originalBounds.height * scale
// move origin
let x = bounds.origin.x - (width - bounds.width)/2
let y = bounds.origin.y - (height - bounds.height)/2
print("new ---- \(CGRect(x: x, y: y, width: width, height: height))")
// Setting the bounds will automatically re-render
bounds = CGRect(x: x, y: y, width: width, height: height)
}
}
/// move center point
var center: CGPoint = .zero {
didSet {
let x = center.x - bounds.width/2.0
let y = center.y - bounds.height/2.0
// Setting the bounds will automatically re-render
bounds = CGRect(origin: CGPoint(x: x, y: y), size: bounds.size)
}
}
public init(bounds: CGRect, image: UIImage) {
self.image = image
originalBounds = bounds
super.init(bounds: bounds, forType: .ink, withProperties: nil)
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func draw(with box: PDFDisplayBox, in context: CGContext) {
super.draw(with: box, in: context)
print("PDFImageAnnotation bounds - \(bounds)")
guard let page = page else {
return
}
UIGraphicsPushContext(context)
context.saveGState()
// rotate annotation
// The origin of the annotation is always at the initial position
let translateX = bounds.width/2 + bounds.origin.x
let translateY = bounds.height/2 + bounds.origin.y
// The page has its own rotation Angle
let newAngle = angle + CGFloat(page.rotation)
context.translateBy(x: translateX, y: translateY)
context.rotate(by: newAngle*(CGFloat.pi/180.0))
context.translateBy(x: -translateX, y: -translateY)
// draw image
if let cgImage = image.cgImage {
context.draw(cgImage, in: bounds)
}
context.restoreGState()
UIGraphicsPopContext()
}
}
use:
extension ViewController: PDFSignAnnotationViewDelegate {
func signAnnotationView(_ view: PDFSignAnnotationView, didMove point: CGPoint) {
guard let page = pdfContainerView.currentPage,
let imageAnnotation = page.annotations.filter({$0.userName == view.identity}).first as? PDFImageAnnotation else {
return
}
let locationOnPage = self.pdfContainerView.convert(point, to: page)
imageAnnotation.center = locationOnPage
}
func signAnnotationView(_ view: PDFSignAnnotationView, didScale scale: CGFloat) {
guard let page = pdfContainerView.currentPage,
let imageAnnotation = page.annotations.filter({$0.userName == view.identity}).first as? PDFImageAnnotation else {
return
}
imageAnnotation.scale = scale
}
func signAnnotationView(_ view: PDFSignAnnotationView, didRotate angle: CGFloat) {
guard let page = pdfContainerView.currentPage,
let imageAnnotation = page.annotations.filter({$0.userName == view.identity}).first as? PDFImageAnnotation else {
return
}
print("didRotate - \(angle)")
imageAnnotation.angle = -angle
}
func signAnnotationView(_ view: PDFSignAnnotationView, close identity: String) {
guard let page = pdfContainerView.currentPage else {
return
}
guard let annotation = page.annotations.filter({$0.userName == identity}).first else {
return
}
page.removeAnnotation(annotation)
}
}
TODO:
Move and zoom the page without sending changes to the upper view
I refer to here: https://medium.com/#rajejones/add-a-signature-to-pdf-using-pdfkit-with-swift-7f13f7faad3e
Demo https://github.com/roMummy/PDFSignature/tree/master/PDFSignature