fix: re-init UIPrinter cause issues with delegate (#1363)

* fix: re-init UIPrinter cause issues with delegate * change selectedPrinters to map of URL:UIPrinter

fix: re-init UIPrinter cause issues with delegate (#1363)
* fix: re-init UIPrinter cause issues with delegate * change selectedPrinters to map of URL:UIPrinter
Hasan · GitHub
Commit 4aef6b8057522dd4b3343668a50f52295edfa0c7 4aef6b80 1 parent f97471a5
Showing 1 changed file with 97 additions and 75 deletions
printing/ios/Classes/PrintJob.swift
--- a/printing/ios/Classes/PrintJob.swift
View file @4aef6b8
+++ b/printing/ios/Classes/PrintJob.swift
View file @4aef6b8
@@ -21,6 +21,10 @@ func dataProviderReleaseDataCallback(info _: UnsafeMutableRawPointer?, data: Uns
     data.deallocate()
 }
+// A variable that holds the selected printers to prevent recreate it if selected again
+// Each printer will be identified by its URL string
+var selectedPrinters = [String: UIPrinter]()
+
 public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate {
     private var printing: PrintingPlugin
     public var index: Int
@@ -32,14 +36,14 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
     private let semaphore = DispatchSemaphore(value: 0)
     private var dynamic = false
     private var currentSize: CGSize?
-
+    
     public init(printing: PrintingPlugin, index: Int) {
         self.printing = printing
         self.index = index
         pdfDocument = nil
         super.init()
     }
-
+    
     override public func drawPage(at pageIndex: Int, in _: CGRect) {
         let ctx = UIGraphicsGetCurrentContext()
         let page = pdfDocument?.page(at: pageIndex + 1)
@@ -49,7 +53,7 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
             ctx?.drawPDFPage(page!)
         }
     }
-
+    
     func cancelJob(_ error: String?) {
         pdfDocument = nil
         if dynamic {
@@ -58,23 +62,23 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
             printing.onCompleted(printJob: self, completed: false, error: error as NSString?)
         }
     }
-
+    
     func setDocument(_ data: Data?) {
         let bytesPointer = UnsafeMutablePointer<UInt8>.allocate(capacity: data?.count ?? 0)
         data?.copyBytes(to: bytesPointer, count: data?.count ?? 0)
         let dataProvider = CGDataProvider(dataInfo: nil, data: bytesPointer, size: data?.count ?? 0, releaseData: dataProviderReleaseDataCallback)
         pdfDocument = CGPDFDocument(dataProvider!)
-
+        
         if dynamic {
             // Unblock the main thread
             semaphore.signal()
             return
         }
-
+        
         DispatchQueue.main.async { [self] in
             let controller = UIPrintInteractionController.shared
             controller.delegate = self
-
+            
             let printInfo = UIPrintInfo.printInfo()
             printInfo.jobName = jobName!
             printInfo.outputType = .general
@@ -84,30 +88,35 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
             }
             controller.printInfo = printInfo
             controller.printPageRenderer = self
-
+            
             if self.printerName != nil {
                 let printerURL = URL(string: self.printerName!)
-
+                
                 if printerURL == nil {
                     self.printing.onCompleted(printJob: self, completed: false, error: "Unable to find printer URL")
                     return
                 }
-
-                let printer = UIPrinter(url: printerURL!)
-                printer.contactPrinter { available in
+                
+                let printerURLString = printerURL!.absoluteString
+                
+                if !selectedPrinters.keys.contains(printerURLString) {
+                    selectedPrinters[printerURLString] = UIPrinter(url: printerURL!)
+                }
+                
+                selectedPrinters[printerURLString]!.contactPrinter { available in
                     if !available {
                         self.printing.onCompleted(printJob: self, completed: false, error: "Printer not available")
                         return
                     }
-
-                    controller.print(to: printer, completionHandler: self.completionHandler)
+                    
+                    controller.print(to: selectedPrinters[printerURLString]!, completionHandler: self.completionHandler)
                 }
             } else {
                 controller.present(animated: true, completionHandler: self.completionHandler)
             }
         }
     }
-
+    
     override public var numberOfPages: Int {
         if dynamic {
             printing.onLayout(
@@ -119,19 +128,19 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
                 marginRight: paperRect.size.width - (printableRect.origin.x + printableRect.size.width),
                 marginBottom: paperRect.size.height - (printableRect.origin.y + printableRect.size.height)
             )
-
+            
             // Block the main thread, waiting for a document
             semaphore.wait()
         }
-
+        
         return pdfDocument?.numberOfPages ?? 0
     }
-
+    
     func completionHandler(printController _: UIPrintInteractionController, completed: Bool, error: Error?) {
         if !completed, error != nil {
             print("Unable to print: \(error?.localizedDescription ?? "unknown error")")
         }
-
+        
         printing.onCompleted(printJob: self, completed: completed, error: error?.localizedDescription as NSString?)
     }
@@ -144,7 +153,7 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
         return bestPaper
     }
-
+    
     func printPdf(name: String, withPageSize size: CGSize, andMargin margin: CGRect, withPrinter printerID: String?, dynamically dyn: Bool) {
         currentSize = size
         dynamic = dyn
@@ -153,17 +162,17 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
             self.printing.onCompleted(printJob: self, completed: false, error: "Printing not available")
             return
         }
-
+        
         if size.width > size.height {
             orientation = UIPrintInfo.Orientation.landscape
         }
-
+        
         jobName = name
         printerName = printerID
-
+        
         let controller = UIPrintInteractionController.shared
         controller.delegate = self
-
+        
         let printInfo = UIPrintInfo.printInfo()
         printInfo.jobName = jobName!
         printInfo.outputType = .general
@@ -173,27 +182,40 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
         }
         controller.printInfo = printInfo
         controller.showsPaperSelectionForLoadedPapers = true
-
+        
         controller.printPageRenderer = self
-
+        
         if printerID != nil {
             let printerURL = URL(string: printerID!)
-
+            
             if printerURL == nil {
                 self.printing.onCompleted(printJob: self, completed: false, error: "Unable to find printer URL")
                 return
             }
-
-            let printer = UIPrinter(url: printerURL!)
-            controller.print(to: printer, completionHandler: completionHandler)
+            
+            let printerURLString = printerURL!.absoluteString
+            
+            if !selectedPrinters.keys.contains(printerURLString) {
+                selectedPrinters[printerURLString] = UIPrinter(url: printerURL!)
+            }
+            
+            
+            selectedPrinters[printerURLString]!.contactPrinter { available in
+                if !available {
+                    self.printing.onCompleted(printJob: self, completed: false, error: "Printer not available")
+                    return
+                }
+                
+                controller.print(to: selectedPrinters[printerURLString]!, completionHandler: self.completionHandler)
+            }
             return
         }
-
+        
         if dynamic {
             controller.present(animated: true, completionHandler: completionHandler)
             return
         }
-
+        
         self.printing.onLayout(
             printJob: self,
             width: size.width,
@@ -204,18 +226,18 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
             marginBottom: size.height - margin.maxY
         )
     }
-
+    
     static func sharePdf(data: Data, withSourceRect rect: CGRect, andName name: String, subject: String?, body: String?) {
         let tmpDirURL = URL(fileURLWithPath: NSTemporaryDirectory(), isDirectory: true)
         let fileURL = tmpDirURL.appendingPathComponent(name)
-
+        
         do {
             try data.write(to: fileURL, options: .atomic)
         } catch {
             print("sharePdf error: \(error.localizedDescription)")
             return
         }
-
+        
         let activityViewController = UIActivityViewController(activityItems: [fileURL, body as Any], applicationActivities: nil)
         activityViewController.setValue(subject, forKey: "subject")
         if UIDevice.current.userInterfaceIdiom == .pad {
@@ -225,7 +247,7 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
         }
         UIApplication.shared.keyWindow?.rootViewController?.present(activityViewController, animated: true)
     }
-
+    
     func convertHtml(_ data: String, withPageSize rect: CGRect, andMargin margin: CGRect, andBaseUrl baseUrl: URL?) {
         let viewController = UIApplication.shared.delegate?.window?!.rootViewController
         let wkWebView = WKWebView(frame: viewController!.view.bounds)
@@ -233,32 +255,32 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
         wkWebView.tag = 100
         viewController?.view.addSubview(wkWebView)
         wkWebView.loadHTMLString(data, baseURL: baseUrl ?? Bundle.main.bundleURL)
-
+        
         urlObservation = wkWebView.observe(\.isLoading, changeHandler: { _, _ in
             // this is workaround for issue with loading local images
             DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
                 // assign the print formatter to the print page renderer
                 let renderer = UIPrintPageRenderer()
                 renderer.addPrintFormatter(wkWebView.viewPrintFormatter(), startingAtPageAt: 0)
-
+                
                 // assign paperRect and printableRect values
                 renderer.setValue(rect, forKey: "paperRect")
                 renderer.setValue(margin, forKey: "printableRect")
-
+                
                 // create pdf context and draw each page
                 let pdfData = NSMutableData()
                 UIGraphicsBeginPDFContextToData(pdfData, rect, nil)
-
+                
                 for i in 0 ..< renderer.numberOfPages {
                     UIGraphicsBeginPDFPage()
                     renderer.drawPage(at: i, in: UIGraphicsGetPDFContextBounds())
                 }
-
+                
                 UIGraphicsEndPDFContext()
-
+                
                 if let viewWithTag = viewController?.view.viewWithTag(wkWebView.tag) {
                     viewWithTag.removeFromSuperview() // remove hidden webview when pdf is generated
-
+                    
                     // clear WKWebView cache
                     if #available(iOS 9.0, *) {
                         WKWebsiteDataStore.default().fetchDataRecords(ofTypes: WKWebsiteDataStore.allWebsiteDataTypes()) { records in
@@ -268,40 +290,40 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
                         }
                     }
                 }
-
+                
                 // dispose urlObservation
                 self.urlObservation = nil
                 self.printing.onHtmlRendered(printJob: self, pdfData: pdfData as Data)
             }
         })
     }
-
+    
     static func pickPrinter(result: @escaping FlutterResult, withSourceRect rect: CGRect) {
         let controller = UIPrinterPickerController(initiallySelectedPrinter: nil)
-
+        
         let pickPrinterCompletionHandler: UIPrinterPickerController.CompletionHandler = {
             (printerPickerController: UIPrinterPickerController, completed: Bool, error: Error?) in
-                if !completed, error != nil {
-                    print("Unable to pick printer: \(error?.localizedDescription ?? "unknown error")")
-                    result(nil)
-                    return
-                }
-
-                if printerPickerController.selectedPrinter == nil {
-                    result(nil)
-                    return
-                }
-
-                let printer = printerPickerController.selectedPrinter!
-                let data: NSDictionary = [
-                    "url": printer.url.absoluteString as Any,
-                    "name": printer.displayName as Any,
-                    "model": printer.makeAndModel as Any,
-                    "location": printer.displayLocation as Any,
-                ]
-                result(data)
+            if !completed, error != nil {
+                print("Unable to pick printer: \(error?.localizedDescription ?? "unknown error")")
+                result(nil)
+                return
+            }
+            
+            if printerPickerController.selectedPrinter == nil {
+                result(nil)
+                return
+            }
+            
+            let printer = printerPickerController.selectedPrinter!
+            let data: NSDictionary = [
+                "url": printer.url.absoluteString as Any,
+                "name": printer.displayName as Any,
+                "model": printer.makeAndModel as Any,
+                "location": printer.displayLocation as Any,
+            ]
+            result(data)
         }
-
+        
         if UIDevice.current.userInterfaceIdiom == .pad {
             let viewController: UIViewController? = UIApplication.shared.keyWindow?.rootViewController
             if viewController != nil {
@@ -309,10 +331,10 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
                 return
             }
         }
-
+        
         controller.present(animated: true, completionHandler: pickPrinterCompletionHandler)
     }
-
+    
     public func rasterPdf(data: Data, pages: [Int]?, scale: CGFloat) {
         guard
             let provider = CGDataProvider(data: data as CFData),
@@ -321,10 +343,10 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
             printing.onPageRasterEnd(printJob: self, error: "Cannot raster a malformed PDF file")
             return
         }
-
+        
         DispatchQueue.global().async {
             let pageCount = document.numberOfPages
-
+            
             for pageNum in pages ?? Array(0 ... pageCount - 1) {
                 guard let page = document.page(at: pageNum + 1) else { continue }
                 let angle = CGFloat(page.rotationAngle) * CGFloat.pi / -180
@@ -333,7 +355,7 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
                 let height = Int(abs((cos(angle) * rect.height + sin(angle) * rect.width) * scale))
                 let stride = width * 4
                 var data = Data(repeating: 0, count: stride * height)
-
+                
                 data.withUnsafeMutableBytes { (outputBytes: UnsafeMutableRawBufferPointer) in
                     let rgb = CGColorSpaceCreateDeviceRGB()
                     let context = CGContext(
@@ -345,7 +367,7 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
                         space: rgb,
                         bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
                     )
-
+                    
                     if context != nil {
                         context!.translateBy(x: CGFloat(width) / 2, y: CGFloat(height) / 2)
                         context!.scaleBy(x: scale, y: scale)
@@ -354,18 +376,18 @@ public class PrintJob: UIPrintPageRenderer, UIPrintInteractionControllerDelegate
                         context!.drawPDFPage(page)
                     }
                 }
-
+                
                 DispatchQueue.main.sync {
                     self.printing.onPageRasterized(printJob: self, imageData: data, width: width, height: height)
                 }
             }
-
+            
             DispatchQueue.main.sync {
                 self.printing.onPageRasterEnd(printJob: self, error: nil)
             }
         }
     }
-
+    
     public static func printingInfo() -> NSDictionary {
         let data: NSDictionary = [
             "directPrint": true,