When PKCanvasView is first drawn, existing drawing objects disappear. PKDrawing, which previously had drawings saved with PKCanvasView, was saved as separate data or file. After that, while creating a new PKCanvasView, I loaded the saved PKDrawing and reflected it in the new PKCanvasView. Below is the code. canvasView!.drawing = draw! Previously saved text or lines will be displayed normally. However, when I draw with the pen for the first time (when I touch the screen with the pen), the old writing or lines disappear. And after I leave a line or text, if I pan across the screen, the old text or line appears again. If this phenomenon occurs and you touch the screen again with the fan, this phenomenon will no longer occur. This phenomenon occurs the first time when a new PKCanvasView is declared and the previously saved PKDrawing is reflected. Could you please help me with why this phenomenon occurs and how to improve it?

Hi, I am trying to make a simple note taking app that users can draw something on pdfview with apple pencil. (I used PDFKit, PencilKit for the code.) I followed the instruction code of WWDC22's "What's new in PDFKit." - "overlayProvider" (so you can see the code at the video.) I was able to draw something each view of pdf page. But the issue was, the resolution of overlayview or subview of pdfview is low. As far as I know, the pkcanvasview draws vertor-based drawings. So I never thought the image or the lines I draw will be that blurry. Is this buggy or is this the normal thing? (+ I added a uibutton as subview of pdfview and the button also looks blurry.) I even tried to scale up the all the subviews when the subviews' layout is done, using contentScaleFactor. PKCanvasView inherits UIScrollView, so I enlarged the frame of pkcanvas view and fixed the scale to below 1.0. If the pkcanvasview looks blurry and that is because somewhat zoomed in wrong way, zooming out should be the solution. But, didn't work. Still blurry. and any other stuff like changing frame or size. So, anyone having same problem with me, or anyone can give me any solution. Please help me. I wish this is bug thing that can be fixed in any moment. -> This image is little bit zoomed in. but the drawing is blurry. and this is the normal pkcanvasview drawing, just subview of view(of VC).

Hi, I have an app using PencilKit that works on VisionOS 1.0. It means, a user can pick an inking tool from PKToolPicker and draw on PKCanvasView. The app is now on available on Vision Pro AppStore as well. However, when I test the app on VisionOS 1.1 RC Simulator, I can pick an inking tool but when I try to draw on the canvas, it just scrolls and no drawing appears on the PKCanvasView. I also noticed that the VisionOS 1.0 Simulator has the FreeForm app where you can draw with PencilKit but the VisionOS 1.1 RC Simulator does not have the FreeForm app. Is this a known issue? Will it be fixed before the release or is there a change in API so I can update the app accordingly? Thanks Zafer

Hello! I've been teaching myself Swift and wanted to challenge myself by creating a drawing app. I want to add a feature that allows the user to share the drawing on their canvas, but I'm having some difficulty. I tried using a ShareLink, but it's asking that I conform in to Transferable. How do I do that? import SwiftUI import PencilKit struct ContentView: View { @State private var canvasView = PKCanvasView() var body: some View { Text("Let's draw!") GeometryReader { geometry in VStack { Spacer() HStack { Spacer() PencilKitView() .frame(width: geometry.size.width * 1, height: geometry.size.height * 0.7) Spacer() } Spacer() } } //share button Button("share with a friend") { let portionRect = CGRect(x: 0, y: 0, width: 100, height: 100) let scale: CGFloat = 1.0 let image = canvasView.drawing.image(from: portionRect, scale: scale) ShareLink( item: image, preview: SharePreview( "Share Preview", image: image ) ) } } } struct PencilKitView: UIViewRepresentable { typealias UIViewType = PKCanvasView let toolPicker = PKToolPicker() func makeUIView(context: Context) -> PKCanvasView { let pencilKitCanvasView = PKCanvasView() pencilKitCanvasView.drawingPolicy = PKCanvasViewDrawingPolicy.anyInput toolPicker.addObserver(pencilKitCanvasView) toolPicker.setVisible(true, forFirstResponder: pencilKitCanvasView) pencilKitCanvasView.becomeFirstResponder() return pencilKitCanvasView } func updateUIView(_ uiView: PKCanvasView, context: Context) { } } #Preview { ContentView() }

In 2 days we have observed in Crashlytics over 50 crashes related to PKDrawing.image with EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000000000210 So far all on iPads with A10, A12 and A13; 100% on iOS 17 (17.1.1, 17.2, 17.3) (while in others the percent of iOS 17 was around 60-80%). Context: Images of the varying frame and scale resulting in screen resolution are being generated sequentially (in a background serial queue called almost one after another when requested), updating one CALayer.contents (and only after this update on Main Thread the next generation is allowed). One zoomable PKCanvasView is present on screen. The crashing line in code: let image = drawing.image(from: frame, scale: renderScale).cgImage The questions: Is there anything that can be done apart from throttling generation? Can the circumstances of the crash be determined – are there any indications accessible in code before calling PKDrawing.image that app might crash? The traces: 0 AGXMetalA12 AGX::BlitContext<AGX::G11::Encoders, AGX::G11::Classes, AGX::G11::ObjClasses>::copyTextureToBuffer(IOGPUMetalResource const*, unsigned long, unsigned long, unsigned long, AGXA12FamilyTexture*, unsigned int, unsigned int, MTLOrigin, MTLSize, unsigned long) + 96 9 PencilKit PKDrawing.image(from:scale:) + 28 0 AGXMetalA13 <redacted> + 96 9 PencilKit PKDrawing.image(from:scale:) + 28 0 AGXMetalA10 <redacted> + 72 9 PencilKit $s9PencilKit9PKDrawingV5image4from5scaleSo7UIImageCSo6CGRectV_12CoreGraphics7CGFloatVtF + 24

Is there any chance to modify the strokes of PKDrawing while drawing in on-process ? since I notice in canvasViewDrawingDidChange is called after drawing stroke is finished My objective is to get realtime feedback modification of PKStroke Thank you in advance

I've noticed in FreeForm app drawing stroke is very nice, like vector object, is there any chance to get the same result of drawing stroke quality like in the FreeForm app ?

I am making a code that uses pencilKit and you can draw on the canvas. However, I want to be able to detect if the resulted drawing is in contact with a Rectangle(). Is there any way to do this? I dont want to use variables for X and Y positions because I have more than 400 rectangles in a grid.

Has anyone got PKToolPicker appearing in an iPad app running in compatibility mode on Vision Pro? In our app, it appears fine on iPad, but not in the Vision Pro simulator. Even though the tools do not appear, I am able to draw in the canvas (...though not change the pen, of course). I did not read anywhere that it was not supported on Vision Pro. I only saw that interactions with pencil do not work, but that other forms of interaction (eg drawing with touch) should work. Anyone seen it working on Vision Pro?

I have a question about an app using PencilKit. I would like to add a UIImageView that is addSubviewed on top of PKCanvasView to PKDrawing and retrieve it as data along with other drawing information using dataRepresentation(). Please tell me how.

I have a question about an app using PencilKit. I would like to add a UIImageView that is addSubviewed on top of PKCanvasView to PKDrawing and retrieve it as data along with other drawing information using dataRepresentation(). Please tell me how.

Hi, I encounter various problems with inserting PKDrawing into a PDFAnnotation : First : After "page.addAnnotation(myCustomAnnotation)", saved document seems corrupted (affected pages are displayed with a "X" watermark covering the whole page), Second : The only way to extract PKDrawing from the annotation is unarchiveTopLevelObjectWithData: which is deprecated, Final : I'm not able to re-read PKDrawings to restore PKCanvasView undoManager. Does anyone have an idea on a correct way to do this? Thank you in advance and happy new year everyone!

I'm trying to add rotation functionality to the PKCanvasView, so that rotation gesture rotates the drawing, I want it to be working together with zoom gesture too, which is already implemented in the PKCanvasView. Rotation works reasonably fine when rotation and zoom can't be performed simultaneously. The moment I enable simultaneous zoom+rotation performance of rotation gets noticably bad. Visually it looks like rotation only happens on noticable angles like 10,20,30.. degrees which looks choppy. Zoom at the same time looks smooth as before. I'm trying to understand why and how to fix this. The rotation gesture handler is here: @objc func handleRotation(_ gesture: UIRotationGestureRecognizer) { guard let curView = gesture.view as? PKCanvasView else {return} if gesture.state == .began || gesture.state == .changed { let rotation = gesture.rotation let gestureCenter = gesture.location(in: curView) let center = CGPoint(x: gestureCenter.x / curView.zoomScale, y: gestureCenter.y / curView.zoomScale) let finalTransform = CGAffineTransform(translationX: -center.x, y: -center.y) .concatenating(CGAffineTransform(rotationAngle: rotation)) .concatenating(CGAffineTransform(translationX: center.x, y: center.y)) curView.drawing.transform(using: finalTransform) gesture.rotation = 0 } } which just constructs rotation matrix around rotation gesture center and calls curView.drawing.transform(using: finalTransform). Rotation matrix is correct I think because without simultaneous zoom+rotation it rotates everything as intended and smoothly under any zoom. (Just for clarity: in the rotation handler the matrix does only the rotation, zoom is done in pinch gesture handler implemented by the PKCanvasView. The zoomScale is used in estimations only to figure out the content coodrinate). The handleRotation method is set as let rotationGestureRecognizer = UIRotationGestureRecognizer(target: self, action: #selector(handleRotation)) rotationGestureRecognizer.delegate = self canvasView.addGestureRecognizer(rotationGestureRecognizer) The simultaneous handling of zoom+rotation I enable with this code: func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool { return true } What I've tried: Tried to nable simultaneous recognition only for zoom+rotation (without the pan gesture and possible others), the effect is the same. For example rotation+pan work smoothly together. I've verified that the gesture handler is called very often, every 8-16 milliseconds (rotation matrix creation and curView.drawing.transform(using: finalTransform) is included in this time period) which should be enough for visually smooth rotation. Other observations: When zoom and rotation both are enabled the rotation sometimes gets completely stuck, zoom and pinch is responsive but rotation is not happening visually. Only when I release fingers from the screen the rotation unstucks and content is rotated as if it didn't stuck at all. During the "stuck" period the rotation handler is called with the same frequency it's just not being visually reflected. Other thoughts: It kind of looks like the tranformation I set in the rotation handler gets overwritten by transformation from the zoom handler. But pan+rotation works fine together which confuses this theory.

When I display the PKToolPicker in my app it looks similar to the image below If you use one of the apps from Apple like Pages or Freeform you see a picker similar to this one. Notice that the PKToolPicker from the Apple app has 6 tools not including the ruler. With the tool all the way to the left being the writing tool. How do you get the picker to display with the writing tool? I have looked over the API and I can see where you can set if the ruler is displayed or not but I can't find anything for the writing tool

Hello. I am developing an app that helps people with language issues communicate and for that I thought I could do a custom keyboard for them. I was wondering if there is a way of doing a 3rd party keyboard using SwiftUI (little to no UIKit) and if so, where can I find documentation/tutorials. I have looked with no success. Additionally, can we use a PKCanvasView inside of keyboards (ie, is there any restriction/policy)? I intend to use it so that users can draw the words they're looking for (I already have the model and know how to come up with the suggestions and everything) Thanks a lot!

I am showing PDF file in QLPreview Controller, in iOS17, after copy and paste the page of pdf and edit the original page using Pencil kit, will affect the duplicate page also. How to restrict? Thanks to all

In iOS whenever you use the PKLassoTool on a set of strokes if you click on the selected region a menu will pop up as you can see here Is there a way to add more buttons to this menu? I tried looking through the Swift docs but I haven't seen this mentioned anywhere.

We've been using PencilKit in our app for a couple of years now, but have run into a significant slowdown recently. It coincided with a shift to iPadOS 17, but possibly that's a coincidence. It seems to occur when we add PKStroke elements to a PKDrawing (programatically). Previously this has refreshed on-screen instantly, but now it's so slow we can sometime see the new stroke progressively drawing on-screen. I profiled the running app and the lag seems to entirely occur within the following call sequence: 2563 -[PKDrawingConcrete addNewStroke:] 2494 -[PKDrawing setNeedsRecognitionUpdate] 2434 -[NSUserDefaults(NSUserDefaults) boolForKey:] 2419 _CFPreferencesGetAppBooleanValueWithContainer 2417 _CFPreferencesCopyAppValueWithContainerAndConfiguration 2399 -[_CFXPreferences copyAppValueForKey:identifier:container:configurationURL:] 2395 -[_CFXPreferences withSearchListForIdentifier:container:cloudConfigurationURL:perform:] 2394 normalizeQuintuplet 2367 __108-[_CFXPreferences(SearchListAdditions) withSearchListForIdentifier:container:cloudConfigurationURL:perform:]_block_invoke 2338 __76-[_CFXPreferences copyAppValueForKey:identifier:container:configurationURL:]_block_invoke 2336 -[CFPrefsSource copyValueForKey:] 2332 -[CFPrefsSearchListSource alreadylocked_copyValueForKey:] 1924 -[CFPrefsSearchListSource alreadylocked_copyValueForKey:].cold.1 1921 _os_log_debug_impl 1918 _os_log 1914 _os_log_impl_flatten_and_send 1829 _os_log_impl_stream 1811 _os_activity_stream_reflect 1205 dispatch_block_perform 1199 _dispatch_block_invoke_direct 1195 _dispatch_client_callout 1194 ___os_activity_stream_reflect_block_invoke 1188 _xpc_pipe_simpleroutine 882 _xpc_send_serializer 867 _xpc_pipe_mach_msg 859 mach_msg 859 mach_msg_overwrite 855 mach_msg2_internal 853 0x1cf7701d8 Up to 'addNewStroke' this makes sense. But where is it going with 'PKDrawing setNeedsRecognitionUpdate'? This ultimately seems to be hitting some kind of lock, which I assume is the cause of the lag. Any suggestions for why this is happening or a means of avoiding it would be much appreciated.

I’m building a drawing app and I want to add more things I can do with the strokes selected by the PKLassoTool. Is there a way to edit the menu of buttons that appears when you make a selection with the lasso tool? And then is there away to pass the selected strokes into a function? I’ve looked at the Apple documentation but there doesn’t seem to be a lot of support to doing anything with the lasso tool.

Since updating to iOS17, lasso no longer works in Pencilkit with SwiftUI support using UIViewRepresentable. It works in PKToolPicker, but the programmatically created PKLassoTool does not work. How can I get lasso to work?