Fix iOS/macOS release build not working

 # Changelog
 
+## 5.0.2
+
+- Fix iOS/macOS release build not working
+
 ## 5.0.1
 
 - Update dependencies

+/*
+ * Copyright (C) 2017, David PHAM-VAN <dev.nfet.net@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#import <printing/printing-Swift.h>
+
+// Dart:ffi API
+
+void net_nfet_printing_set_document(uint32_t job,
+                                    const uint8_t* doc,
+                                    uint64_t size) {
+  [PrintingPlugin setDocumentWithJob:job doc:doc size:size];
+}
+
+void net_nfet_printing_set_error(uint32_t job, const char* message) {
+  [PrintingPlugin setErrorWithJob:job message:message];
+}

@@ -17,29 +17,26 @@
 import Flutter
 import Foundation
 
-// Dart:ffi API
-private var _printingPlugin: PrintingPlugin?
-
-@_cdecl("net_nfet_printing_set_document")
-func setDocument(job: UInt32, doc: UnsafePointer<UInt8>, size: UInt64) {
-    _printingPlugin!.jobs[job]?.setDocument(Data(bytes: doc, count: Int(size)))
-}
-
-@_cdecl("net_nfet_printing_set_error")
-func setError(job: UInt32, message: UnsafePointer<CChar>) {
-    _printingPlugin!.jobs[job]?.cancelJob(String(cString: message))
-}
-
-// End of Dart:ffi API
-
+@objc
 public class PrintingPlugin: NSObject, FlutterPlugin {
+    private static var instance: PrintingPlugin?
     private var channel: FlutterMethodChannel
     public var jobs = [UInt32: PrintJob]()
 
     init(_ channel: FlutterMethodChannel) {
         self.channel = channel
         super.init()
-        _printingPlugin = self
+        PrintingPlugin.instance = self
+    }
+
+    @objc
+    public static func setDocument(job: UInt32, doc: UnsafePointer<UInt8>, size: UInt64) {
+        instance!.jobs[job]?.setDocument(Data(bytes: doc, count: Int(size)))
+    }
+
+    @objc
+    public static func setError(job: UInt32, message: UnsafePointer<CChar>) {
+        instance!.jobs[job]?.cancelJob(String(cString: message))
     }
 
     /// Entry point

+/*
+ * Copyright (C) 2017, David PHAM-VAN <dev.nfet.net@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#import <printing/printing-Swift.h>
+
+// Dart:ffi API
+
+void net_nfet_printing_set_document(uint32_t job,
+                                    const uint8_t* doc,
+                                    uint64_t size) {
+  [PrintingPlugin setDocumentWithJob:job doc:doc size:size];
+}
+
+void net_nfet_printing_set_error(uint32_t job, const char* message) {
+  [PrintingPlugin setErrorWithJob:job message:message];
+}

@@ -17,29 +17,26 @@
 import FlutterMacOS
 import Foundation
 
-// Dart:ffi API
-private var _printingPlugin: PrintingPlugin?
-
-@_cdecl("net_nfet_printing_set_document")
-func setDocument(job: UInt32, doc: UnsafePointer<UInt8>, size: UInt64) {
-    _printingPlugin!.jobs[job]?.setDocument(Data(bytes: doc, count: Int(size)))
-}
-
-@_cdecl("net_nfet_printing_set_error")
-func setError(job: UInt32, message: UnsafePointer<CChar>) {
-    _printingPlugin!.jobs[job]?.cancelJob(String(cString: message))
-}
-
-// End of Dart:ffi API
-
+@objc
 public class PrintingPlugin: NSObject, FlutterPlugin {
+    private static var instance: PrintingPlugin?
     private var channel: FlutterMethodChannel
     public var jobs = [UInt32: PrintJob]()
 
     init(_ channel: FlutterMethodChannel) {
         self.channel = channel
         super.init()
-        _printingPlugin = self
+        PrintingPlugin.instance = self
+    }
+
+    @objc
+    public static func setDocument(job: UInt32, doc: UnsafePointer<UInt8>, size: UInt64) {
+        instance!.jobs[job]?.setDocument(Data(bytes: doc, count: Int(size)))
+    }
+
+    @objc
+    public static func setError(job: UInt32, message: UnsafePointer<CChar>) {
+        instance!.jobs[job]?.cancelJob(String(cString: message))
     }
 
     /// Entry point

@@ -7,7 +7,7 @@ description: >
 homepage: https://github.com/DavBfr/dart_pdf/tree/master/printing
 repository: https://github.com/DavBfr/dart_pdf
 issue_tracker: https://github.com/DavBfr/dart_pdf/issues
-version: 5.0.1
+version: 5.0.2
 
 environment:
   sdk: ">=2.12.0-0 <3.0.0"