I'm fairly new to Swift programming and I've created an app for work to simplify a task where I programmatically fill-in fields on an existing PDF. I've captured a signature as a UIImage and I'd like to add this to the PDF as an annotation like the rest of the fields. Is this possible?
// Annotate Signature
let signatureFieldBounds = CGRect(x:390, y:142, width:100, height:30)
let signatureField = PDFAnnotation(bounds: signatureFieldBounds, forType: .stamp, withProperties: nil)
signatureField.fieldName = FieldNames.signature.rawValue
signatureField.backgroundColor = UIColor.clear
sigImage?.draw(in: signatureFieldBounds)
page.addAnnotation(signatureField)
I've also tried: signatureField.stampName = sigImage as! UIImage instead of the draw function but this gives the error 'Cannot assign value of type 'UIImage' to type 'String?''
The screenshot shows what I get annotated:
Any help at all would be greatly appreciated!!
This was tricky for me too, but I figured it out.
Create a custom PDFAnnotation, then override the draw method to draw the image in the pdf context.
class ImageStampAnnotation: PDFAnnotation {
var image: UIImage!
// A custom init that sets the type to Stamp on default and assigns our Image variable
init(with image: UIImage!, forBounds bounds: CGRect, withProperties properties: [AnyHashable : Any]?) {
super.init(bounds: bounds, forType: PDFAnnotationSubtype.stamp, withProperties: properties)
self.image = image
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func draw(with box: PDFDisplayBox, in context: CGContext) {
// Get the CGImage of our image
guard let cgImage = self.image.cgImage else { return }
// Draw our CGImage in the context of our PDFAnnotation bounds
context.draw(cgImage, in: self.bounds)
}
}
Then, just add it to the document
guard let signatureImage = signatureImage, let page = pdfContainerView.currentPage else { return }
let pageBounds = page.bounds(for: .cropBox)
let imageBounds = CGRect(x: pageBounds.midX, y: pageBounds.midY, width: 200, height: 100)
let imageStamp = ImageStampAnnotation(with: signatureImage, forBounds: imageBounds, withProperties: nil)
page.addAnnotation(imageStamp)
I wrote a medium article on how I did it, added a gesture recognizer to it and a canvas to grab a signature:
https://medium.com/#rajejones/add-a-signature-to-pdf-using-pdfkit-with-swift-7f13f7faad3e
Related
A gif image is loaded into a UIImageView (by using this extension) and another UIImageView is overlaid on it. Everything works fine but the problem is when I going for combine both via below code, it shows a still image (.jpg). I wanna combine both and after combine it should be a animated image (.gif) too.
let bottomImage = gifPlayer.image
let topImage = UIImage
let size = CGSize(width: (bottomImage?.size.width)!, height: (bottomImage?.size.height)!)
UIGraphicsBeginImageContext(size)
let areaSize = CGRect(x: 0, y: 0, width: size.width, height: size.height)
bottomImage!.draw(in: areaSize)
topImage!.draw(in: areaSize, blendMode: .normal, alpha: 0.8)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
Click here to know more about this problem please.
When using an animated GIF in a UIImageView, it becomes an array of UIImage.
We can set that array with (for example):
imageView.animationImages = arrayOfImages
imageView.animationDuration = 1.0
or, we can set the .image property to an animatedImage -- that's how the GIF-Swift code you are using works:
if let img = UIImage.gifImageWithName("funny") {
bottomImageView.image = img
}
in that case, the image also contains the duration:
img.images?.duration
So, to generate a new animated GIF with the border/overlay image, you need to get that array of images and generate each "frame" with the border added to it.
Here's a quick example...
This assumes:
you are using GIF-Swift
you have added bottomImageView and topImageView in Storyboard
you have a GIF in the bundle named "funny.gif" (edit the code if yours is different)
you have a "border.png" in assets (again, edit the code as needed)
and you have a button to connect to the #IBAction:
import UIKit
import ImageIO
import UniformTypeIdentifiers
class animImageViewController: UIViewController {
#IBOutlet var bottomImageView: UIImageView!
#IBOutlet var topImageView: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
if let img = UIImage.gifImageWithName("funny") {
bottomImageView.image = img
}
if let img = UIImage(named: "border") {
topImageView.image = img
}
}
#IBAction func saveButtonTapped(_ sender: Any) {
generateNewGif(from: bottomImageView, with: topImageView)
}
func generateNewGif(from animatedImageView: UIImageView, with overlayImageView: UIImageView) {
var images: [UIImage]!
var delayTime: Double!
guard let overlayImage = overlayImageView.image else {
print("Could not get top / overlay image!")
return
}
if let imgs = animatedImageView.image?.images {
// the image view is using .image = animatedImage
// unwrap the duration
if let dur = animatedImageView.image?.duration {
images = imgs
delayTime = dur / Double(images.count)
} else {
print("Image view is using an animatedImage, but could not get the duration!" )
return
}
} else if let imgs = animatedImageView.animationImages {
// the image view is using .animationImages
images = imgs
delayTime = animatedImageView.animationDuration / Double(images.count)
} else {
print("Could not get images array!")
return
}
// we now have a valid [UIImage] array, and
// a valid inter-frame duration, and
// a valid "overlay" UIImage
// generate unique file name
let destinationFilename = String(NSUUID().uuidString + ".gif")
// create empty file in temp folder to hold gif
let destinationURL = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(destinationFilename)
// metadata for gif file to describe it as an animated gif
let fileDictionary = [kCGImagePropertyGIFDictionary : [kCGImagePropertyGIFLoopCount : 0]]
// create the file and set the file properties
guard let animatedGifFile = CGImageDestinationCreateWithURL(destinationURL as CFURL, UTType.gif.identifier as CFString, images.count, nil) else {
print("error creating file")
return
}
CGImageDestinationSetProperties(animatedGifFile, fileDictionary as CFDictionary)
let frameDictionary = [kCGImagePropertyGIFDictionary : [kCGImagePropertyGIFDelayTime: delayTime]]
// use original size of gif
let sz: CGSize = images[0].size
let renderer: UIGraphicsImageRenderer = UIGraphicsImageRenderer(size: sz)
// loop through the images
// drawing the top/border image on top of each "frame" image with 80% alpha
// then writing the combined image to the gif file
images.forEach { img in
let combinedImage = renderer.image { ctx in
img.draw(at: .zero)
overlayImage.draw(in: CGRect(origin: .zero, size: sz), blendMode: .normal, alpha: 0.8)
}
guard let cgFrame = combinedImage.cgImage else {
print("error creating cgImage")
return
}
// add the combined image to the new animated gif
CGImageDestinationAddImage(animatedGifFile, cgFrame, frameDictionary as CFDictionary)
}
// done writing
CGImageDestinationFinalize(animatedGifFile)
print("New GIF created at:")
print(destinationURL)
print()
// do something with the newly created file...
// maybe move it to documents folder, or
// upload it somewhere, or
// save to photos library, etc
}
}
Notes:
the code is based on this article: How to Make an Animated GIF Using Swift
this should be considered Example Code Only!!! -- a starting-point for you, not a "production ready" solution.
I have a class to edit pdf by inserting an image into the pdf and save a new pdf with the inserted image.
Below code is the way I use to achieve the scenario, by creating a custom PDFAnnotation. I specify type as .widget instead of .stamp to avoid having black line drawing across diagonal.
final private class PDFImageAnnotation: PDFAnnotation {
var image: UIImage?
convenience init(_ image: UIImage?, bounds: CGRect, properties: [AnyHashable: Any]?) {
self.init(bounds: bounds, forType: PDFAnnotationSubtype.widget, withProperties: properties)
self.image = image
}
override func draw(with box: PDFDisplayBox, in context: CGContext) {
super.draw(with: box, in: context)
// Drawing the image within the annotation's bounds.
guard let cgImage = image?.cgImage else { return }
context.draw(cgImage, in: bounds)
}
}
Below is how I display pdf and select image to save in pdf
private func setupPDF() {
guard let url = url else { return }
pdfView.document = PDFDocument(url: url)
pdfView.autoScales = true
}
private func addImageAndSave(_ image: UIImage) {
guard let page = pdfView.currentPage else { return }
let pageBounds = page.bounds(for: .cropBox)
let imageBounds = CGRect(x: pageBounds.midX, y: pageBounds.midY, width: image.size.width, height: image.size.height)
let imageStamp = PDFImageAnnotation(image, bounds: imageBounds, properties: nil)
imageStamp.shouldDisplay = true
imageStamp.shouldPrint = true
page.addAnnotation(imageStamp)
// Save PDF with image
let fileName = url.lastPathComponent
let saveUrl = FileManager.default.temporaryDirectory.appendingPathComponent(fileName, isDirectory: false)
pdfView.document?.write(to: saveUrl)
}
However the result pdf file is below
The preview on right column does display the picture but when open the pdf in Preview app or any browser the picture is not there.
How can I make the picture appear in the final pdf file?
Thanks.
I have to also draw that image on PDFPage to make them appear in the saved pdf file
final private class ImagePDFPage: PDFPage {
/// A flag indicates whether to draw image on a page
///
/// - Note: Set this to `true` before write pdf to file otherwise the image will not be appeared in pdf file
var saveImageToPDF: Bool = false
private var imageAnnotation: EkoPDFImageAnnotation? = nil
func addImageAnnotation(_ annotation: EkoPDFImageAnnotation) {
imageAnnotation = annotation
addAnnotation(annotation)
}
func removeImageAnnotation() {
guard let imageAnnotation = imageAnnotation else { return }
self.imageAnnotation = nil
removeAnnotation(imageAnnotation)
}
override func draw(with box: PDFDisplayBox, to context: CGContext) {
super.draw(with: box, to: context)
guard saveImageToPDF,
let annotation = imageAnnotation,
let cgImage = annotation.image?.cgImage else { return }
context.draw(cgImage, in: annotation.bounds)
}
}
and update PDFDocument.delegate to tell to use ImagePDFPage as a class for pdf page
extension PDFEditorViewController: PDFDocumentDelegate {
func classForPage() -> AnyClass {
return ImagePDFPage.self
}
}
The result
The following code:
let skView = SKView()
let scene = SKScene()
override func viewDidLoad() {
super.viewDidLoad()
self.scene.scaleMode = .resizeFill
self.skView.presentScene(self.scene)
self.scene.backgroundColor = UIColor.black
self.view.addSubview(skView)
self.scene.shouldEnableEffects = true
let sprite = SKSpriteNode(imageNamed: "NAME_THAT_PIC")
sprite.position = CGPoint(x: 300, y: 400)
let effectNode = SKEffectNode()
effectNode.filter = MyFilter()
effectNode.addChild(sprite)
will call this custom filter that does nothing but create a CGImage from a CIImage, correctly invoking context.createCGImage() as reported by many people (CIImages are not pixel buffered.)
MyFilter is reduced to a simple repro test:
class MyFilter: CIFilter {
var inputImage: CIImage?
var inputImageRect: CGRect? {
guard let image = self.inputImage else {
return nil
}
return image.extent
}
public override init() {
super.init()
}
required public init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override open var outputImage: CIImage? {
guard let inputImage = self.inputImage else {
return nil
}
let context = CIContext(options:nil)
let cgImage = context.createCGImage(inputImage, from: inputImageRect!)
// ... DO SOMETHING WITH CGIMAGE DATA ...
return CIImage(cgImage: cgImage!)
}
}
If I replace MyFilter() by another built-in filter, it works and will show the altered image so the viewcontroller code works. If instead, I return inputImage directly from the filter output call, it works and the image passed in will display.
When I dump the CGImage, the dimensions of the image are correct but every pixels are set to black.
I tried creating a UIImage using UIImage(cgImage: cgImage!) but the same happens.
What is causing pixels not to be loaded in the cgImage I generated from the inputImage?
In one of my app. i am facing issue of app crash because of i am unable to clean memory of node material diffuse content. when i am trying load node at that time memory is keeping up so i want clear memory whenever remove node from parent. please suggest approbate solution.
Here is below my code:
let recomondationView = viewRecomodation as! THARRecomondationsView
planeGeoMetryP1.firstMaterial?.diffuse.contents = UIImage.imageWithView(view: recomondationView)
oldAnnotationNode.name = name
oldAnnotationNode.geometry = planeGeoMetryP1
let billboardConstraint = SCNBillboardConstraint()
billboardConstraint.freeAxes = SCNBillboardAxis.Y
self.constraints = [billboardConstraint]
self.addChildNode(oldAnnotationNode)
Here is method of convert UIView to UIImage
extension UIImage {
class func imageWithView(view: UIView) -> UIImage {
var image = UIImage()
UIGraphicsBeginImageContextWithOptions(view.frame.size, true, 1.0)
let renderer = UIGraphicsImageRenderer(size: view.bounds.size)
image = renderer.image { ctx in
view.drawHierarchy(in: view.bounds, afterScreenUpdates: true)
}
UIGraphicsEndImageContext()
return image
}
}
Here is the code that i am using to remove node from parent
if let index = self.sceneNode?.childNodes.index(of: locationNode) {
self.sceneNode?.childNodes[index].geometry = nil
self.sceneNode?.childNodes[index].removeFromParentNode()
}
Is there a way to take a screenshot of mapView and include the polyline? I believe I need to draw CGPoint's on the image that the MKSnapShotter returns, but I am unsure on how to do so.
Current code
func takeSnapshot(mapView: MKMapView, withCallback: (UIImage?, NSError?) -> ()) {
let options = MKMapSnapshotOptions()
options.region = mapView.region
options.size = mapView.frame.size
options.scale = UIScreen.main().scale
let snapshotter = MKMapSnapshotter(options: options)
snapshotter.start() { snapshot, error in
guard snapshot != nil else {
withCallback(nil, error)
return
}
if let image = snapshot?.image{
withCallback(image, nil)
for coordinate in self.area {
image.draw(at:snapshot!.point(for: coordinate))
}
}
}
}
I had the same problem today. After several hours of research, here is how I solve it.
The following codes are in Swift 3.
1. Init your polyline coordinates array
// initial this array with your polyline coordinates
var yourCoordinates = [CLLocationCoordinate2D]()
yourCoorinates.append( coordinate 1 )
yourCoorinates.append( coordinate 2 )
...
// you can use any data structure you like
2. take the snapshot as usual, but set the region based on your coordinates:
func takeSnapShot() {
let mapSnapshotOptions = MKMapSnapshotOptions()
// Set the region of the map that is rendered. (by polyline)
let polyLine = MKPolyline(coordinates: &yourCoordinates, count: yourCoordinates.count)
let region = MKCoordinateRegionForMapRect(polyLine.boundingMapRect)
mapSnapshotOptions.region = region
// Set the scale of the image. We'll just use the scale of the current device, which is 2x scale on Retina screens.
mapSnapshotOptions.scale = UIScreen.main.scale
// Set the size of the image output.
mapSnapshotOptions.size = CGSize(width: IMAGE_VIEW_WIDTH, height: IMAGE_VIEW_HEIGHT)
// Show buildings and Points of Interest on the snapshot
mapSnapshotOptions.showsBuildings = true
mapSnapshotOptions.showsPointsOfInterest = true
let snapShotter = MKMapSnapshotter(options: mapSnapshotOptions)
snapShotter.start() { snapshot, error in
guard let snapshot = snapshot else {
return
}
// Don't just pass snapshot.image, pass snapshot itself!
self.imageView.image = self.drawLineOnImage(snapshot: snapshot)
}
}
3. Use snapshot.point() to draw Polylines on Snapshot Image
func drawLineOnImage(snapshot: MKMapSnapshot) -> UIImage {
let image = snapshot.image
// for Retina screen
UIGraphicsBeginImageContextWithOptions(self.imageView.frame.size, true, 0)
// draw original image into the context
image.draw(at: CGPoint.zero)
// get the context for CoreGraphics
let context = UIGraphicsGetCurrentContext()
// set stroking width and color of the context
context!.setLineWidth(2.0)
context!.setStrokeColor(UIColor.orange.cgColor)
// Here is the trick :
// We use addLine() and move() to draw the line, this should be easy to understand.
// The diificult part is that they both take CGPoint as parameters, and it would be way too complex for us to calculate by ourselves
// Thus we use snapshot.point() to save the pain.
context!.move(to: snapshot.point(for: yourCoordinates[0]))
for i in 0...yourCoordinates.count-1 {
context!.addLine(to: snapshot.point(for: yourCoordinates[i]))
context!.move(to: snapshot.point(for: yourCoordinates[i]))
}
// apply the stroke to the context
context!.strokePath()
// get the image from the graphics context
let resultImage = UIGraphicsGetImageFromCurrentImageContext()
// end the graphics context
UIGraphicsEndImageContext()
return resultImage!
}
That's it, hope this helps someone.
References
How do I draw on an image in Swift?
MKTile​Overlay,MKMap​Snapshotter & MKDirections
Creating an MKMapSnapshotter with an MKPolylineRenderer
Render a Map as an Image using MapKit
What is wrong with:
snapshotter.start( completionHandler: { snapshot, error in
guard snapshot != nil else {
withCallback(nil, error)
return
}
if let image = snapshot?.image {
withCallback(image, nil)
for coordinate in self.area {
image.draw(at:snapshot!.point(for: coordinate))
}
}
})
If you just want a copy of the image the user sees in the MKMapView, remember that it's a UIView subclass, and so you could do this...
public extension UIView {
public var snapshot: UIImage? {
get {
UIGraphicsBeginImageContextWithOptions(self.bounds.size, false, UIScreen.main.scale)
self.drawHierarchy(in: self.bounds, afterScreenUpdates: true)
let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}
}
}
// ...
if let img = self.mapView.snapshot {
// Do something
}