Migrate to the new Android plugins APIs

 # Changelog
 
+## 3.1.0
+
+- Migrate to the new Android plugins APIs
+
 ## 3.0.2
 
 - Add Raster PDF to Image

+package net.nfet.flutter.printing;
+
+import android.app.Activity;
+import android.print.PrintAttributes;
+
+import androidx.annotation.NonNull;
+
+import java.util.HashMap;
+
+import io.flutter.plugin.common.MethodCall;
+import io.flutter.plugin.common.MethodChannel;
+
+public class PrintingHandler implements MethodChannel.MethodCallHandler {
+    private final Activity activity;
+    private final MethodChannel channel;
+
+    public PrintingHandler(@NonNull Activity activity, @NonNull MethodChannel channel) {
+        this.activity = activity;
+        this.channel = channel;
+    }
+
+    @Override
+    public void onMethodCall(@NonNull MethodCall call, @NonNull MethodChannel.Result result) {
+        switch (call.method) {
+            case "printPdf": {
+                final String name = call.argument("name");
+                final Double width = call.argument("width");
+                final Double height = call.argument("height");
+                final Double marginLeft = call.argument("marginLeft");
+                final Double marginTop = call.argument("marginTop");
+                final Double marginRight = call.argument("marginRight");
+                final Double marginBottom = call.argument("marginBottom");
+
+                final PrintingJob printJob =
+                        new PrintingJob(activity, this, (int) call.argument("job"));
+                assert name != null;
+                printJob.printPdf(
+                        name, width, height, marginLeft, marginTop, marginRight, marginBottom);
+
+                result.success(1);
+                break;
+            }
+            case "cancelJob": {
+                final PrintingJob printJob =
+                        new PrintingJob(activity, this, (int) call.argument("job"));
+                printJob.cancelJob();
+                result.success(1);
+                break;
+            }
+            case "sharePdf": {
+                final byte[] document = call.argument("doc");
+                final String name = call.argument("name");
+                PrintingJob.sharePdf(activity, document, name);
+                result.success(1);
+                break;
+            }
+            case "convertHtml": {
+                Double width = call.argument("width");
+                Double height = call.argument("height");
+                Double marginLeft = call.argument("marginLeft");
+                Double marginTop = call.argument("marginTop");
+                Double marginRight = call.argument("marginRight");
+                Double marginBottom = call.argument("marginBottom");
+                final PrintingJob printJob =
+                        new PrintingJob(activity, this, (int) call.argument("job"));
+
+                assert width != null;
+                assert height != null;
+                assert marginLeft != null;
+                assert marginTop != null;
+                assert marginRight != null;
+                assert marginBottom != null;
+
+                PrintAttributes.Margins margins =
+                        new PrintAttributes.Margins(Double.valueOf(marginLeft * 1000.0).intValue(),
+                                Double.valueOf(marginTop * 1000.0 / 72.0).intValue(),
+                                Double.valueOf(marginRight * 1000.0 / 72.0).intValue(),
+                                Double.valueOf(marginBottom * 1000.0 / 72.0).intValue());
+
+                PrintAttributes.MediaSize size = new PrintAttributes.MediaSize("flutter_printing",
+                        "Provided size", Double.valueOf(width * 1000.0 / 72.0).intValue(),
+                        Double.valueOf(height * 1000.0 / 72.0).intValue());
+
+                printJob.convertHtml((String) call.argument("html"), size, margins,
+                        (String) call.argument("baseUrl"));
+                result.success(1);
+                break;
+            }
+            case "printingInfo": {
+                result.success(PrintingJob.printingInfo());
+                break;
+            }
+            case "rasterPdf": {
+                final byte[] document = call.argument("doc");
+                final int[] pages = call.argument("pages");
+                Double scale = call.argument("scale");
+                final PrintingJob printJob =
+                        new PrintingJob(activity, this, (int) call.argument("job"));
+                printJob.rasterPdf(document, pages, scale);
+                result.success(1);
+                break;
+            }
+            default:
+                result.notImplemented();
+                break;
+        }
+    }
+
+    /// Request the Pdf document from flutter
+    void onLayout(final PrintingJob printJob, Double width, double height, double marginLeft,
+            double marginTop, double marginRight, double marginBottom) {
+        HashMap<String, Object> args = new HashMap<>();
+        args.put("width", width);
+        args.put("height", height);
+
+        args.put("marginLeft", marginLeft);
+        args.put("marginTop", marginTop);
+        args.put("marginRight", marginRight);
+        args.put("marginBottom", marginBottom);
+        args.put("job", printJob.index);
+
+        channel.invokeMethod("onLayout", args, new MethodChannel.Result() {
+            @Override
+            public void success(Object result) {
+                if (result instanceof byte[]) {
+                    printJob.setDocument((byte[]) result);
+                } else {
+                    printJob.cancelJob();
+                }
+            }
+
+            @Override
+            public void error(String errorCode, String errorMessage, Object errorDetails) {
+                printJob.cancelJob();
+            }
+
+            @Override
+            public void notImplemented() {
+                printJob.cancelJob();
+            }
+        });
+    }
+
+    /// send completion status to flutter
+    void onCompleted(PrintingJob printJob, boolean completed, String error) {
+        HashMap<String, Object> args = new HashMap<>();
+        args.put("completed", completed);
+
+        args.put("error", error);
+        args.put("job", printJob.index);
+
+        channel.invokeMethod("onCompleted", args);
+    }
+
+    /// send html to pdf data result to flutter
+    void onHtmlRendered(PrintingJob printJob, byte[] pdfData) {
+        HashMap<String, Object> args = new HashMap<>();
+        args.put("doc", pdfData);
+        args.put("job", printJob.index);
+
+        channel.invokeMethod("onHtmlRendered", args);
+    }
+
+    /// send html to pdf conversion error to flutter
+    void onHtmlError(PrintingJob printJob, String error) {
+        HashMap<String, Object> args = new HashMap<>();
+        args.put("error", error);
+        args.put("job", printJob.index);
+
+        channel.invokeMethod("onHtmlError", args);
+    }
+
+    /// send pdf to raster data result to flutter
+    void onPageRasterized(PrintingJob printJob, byte[] imageData, int width, int height) {
+        HashMap<String, Object> args = new HashMap<>();
+        args.put("image", imageData);
+        args.put("width", width);
+        args.put("height", height);
+        args.put("job", printJob.index);
+
+        channel.invokeMethod("onPageRasterized", args);
+    }
+
+    void onPageRasterEnd(PrintingJob printJob) {
+        HashMap<String, Object> args = new HashMap<>();
+        args.put("job", printJob.index);
+
+        channel.invokeMethod("onPageRasterEnd", args);
+    }
+}

@@ -58,14 +58,14 @@ import java.util.HashMap;
 public class PrintingJob extends PrintDocumentAdapter {
     private static PrintManager printManager;
     private final Context context;
-    private final PrintingPlugin printing;
+    private final PrintingHandler printing;
     private PrintJob printJob;
     private byte[] documentData;
     private String jobName;
     private LayoutResultCallback callback;
     int index;
 
-    PrintingJob(Context context, PrintingPlugin printing, int index) {
+    PrintingJob(Context context, PrintingHandler printing, int index) {
         this.context = context;
         this.printing = printing;
         this.index = index;

@@ -17,12 +17,18 @@
 package net.nfet.flutter.printing;
 
 import android.app.Activity;
+import android.content.Context;
 import android.print.PrintAttributes;
 
 import androidx.annotation.NonNull;
 
 import java.util.HashMap;
 
+import io.flutter.embedding.engine.plugins.FlutterPlugin;
+import io.flutter.embedding.engine.plugins.activity.ActivityAware;
+import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding;
+import io.flutter.plugin.common.BinaryMessenger;
+import io.flutter.plugin.common.EventChannel;
 import io.flutter.plugin.common.MethodCall;
 import io.flutter.plugin.common.MethodChannel;
 import io.flutter.plugin.common.MethodChannel.MethodCallHandler;
@@ -32,17 +38,14 @@ import io.flutter.plugin.common.PluginRegistry.Registrar;
 /**
  * PrintingPlugin
  */
-public class PrintingPlugin implements MethodCallHandler {
-    private final Activity activity;
-    private final MethodChannel channel;
-
-    private PrintingPlugin(@NonNull Activity activity, @NonNull MethodChannel channel) {
-        this.activity = activity;
-        this.channel = channel;
-    }
+public class PrintingPlugin implements FlutterPlugin, ActivityAware {
+    private Activity activity;
+    private MethodChannel channel;
+    private PrintingHandler handler;
 
     /**
      * Plugin registration.
+     * for legacy Embedding API
      */
     public static void registerWith(Registrar registrar) {
         Activity activity = registrar.activity();
@@ -50,176 +53,60 @@ public class PrintingPlugin implements MethodCallHandler {
             return; // We can't print without an activity
         }
 
-        final MethodChannel channel = new MethodChannel(registrar.messenger(), "net.nfet.printing");
-        channel.setMethodCallHandler(new PrintingPlugin(activity, channel));
+        final PrintingPlugin instance = new PrintingPlugin();
+        instance.onAttachedToEngine(registrar.messenger());
+        instance.onAttachedToActivity(activity);
     }
 
     @Override
-    public void onMethodCall(@NonNull MethodCall call, @NonNull Result result) {
-        switch (call.method) {
-            case "printPdf": {
-                final String name = call.argument("name");
-                final Double width = call.argument("width");
-                final Double height = call.argument("height");
-                final Double marginLeft = call.argument("marginLeft");
-                final Double marginTop = call.argument("marginTop");
-                final Double marginRight = call.argument("marginRight");
-                final Double marginBottom = call.argument("marginBottom");
-
-                final PrintingJob printJob =
-                        new PrintingJob(activity, this, (int) call.argument("job"));
-                assert name != null;
-                printJob.printPdf(
-                        name, width, height, marginLeft, marginTop, marginRight, marginBottom);
-
-                result.success(1);
-                break;
-            }
-            case "cancelJob": {
-                final PrintingJob printJob =
-                        new PrintingJob(activity, this, (int) call.argument("job"));
-                printJob.cancelJob();
-                result.success(1);
-                break;
-            }
-            case "sharePdf": {
-                final byte[] document = call.argument("doc");
-                final String name = call.argument("name");
-                PrintingJob.sharePdf(activity, document, name);
-                result.success(1);
-                break;
-            }
-            case "convertHtml": {
-                Double width = call.argument("width");
-                Double height = call.argument("height");
-                Double marginLeft = call.argument("marginLeft");
-                Double marginTop = call.argument("marginTop");
-                Double marginRight = call.argument("marginRight");
-                Double marginBottom = call.argument("marginBottom");
-                final PrintingJob printJob =
-                        new PrintingJob(activity, this, (int) call.argument("job"));
-
-                assert width != null;
-                assert height != null;
-                assert marginLeft != null;
-                assert marginTop != null;
-                assert marginRight != null;
-                assert marginBottom != null;
-
-                PrintAttributes.Margins margins =
-                        new PrintAttributes.Margins(Double.valueOf(marginLeft * 1000.0).intValue(),
-                                Double.valueOf(marginTop * 1000.0 / 72.0).intValue(),
-                                Double.valueOf(marginRight * 1000.0 / 72.0).intValue(),
-                                Double.valueOf(marginBottom * 1000.0 / 72.0).intValue());
-
-                PrintAttributes.MediaSize size = new PrintAttributes.MediaSize("flutter_printing",
-                        "Provided size", Double.valueOf(width * 1000.0 / 72.0).intValue(),
-                        Double.valueOf(height * 1000.0 / 72.0).intValue());
-
-                printJob.convertHtml((String) call.argument("html"), size, margins,
-                        (String) call.argument("baseUrl"));
-                result.success(1);
-                break;
-            }
-            case "printingInfo": {
-                result.success(PrintingJob.printingInfo());
-                break;
-            }
-            case "rasterPdf": {
-                final byte[] document = call.argument("doc");
-                final int[] pages = call.argument("pages");
-                Double scale = call.argument("scale");
-                final PrintingJob printJob =
-                        new PrintingJob(activity, this, (int) call.argument("job"));
-                printJob.rasterPdf(document, pages, scale);
-                result.success(1);
-                break;
-            }
-            default:
-                result.notImplemented();
-                break;
-        }
+    public void onAttachedToEngine(FlutterPluginBinding binding) {
+        onAttachedToEngine(binding.getBinaryMessenger());
     }
 
-    /// Request the Pdf document from flutter
-    void onLayout(final PrintingJob printJob, Double width, double height, double marginLeft,
-            double marginTop, double marginRight, double marginBottom) {
-        HashMap<String, Object> args = new HashMap<>();
-        args.put("width", width);
-        args.put("height", height);
+    private void onAttachedToEngine(BinaryMessenger messenger) {
+        channel = new MethodChannel(messenger, "net.nfet.printing");
 
-        args.put("marginLeft", marginLeft);
-        args.put("marginTop", marginTop);
-        args.put("marginRight", marginRight);
-        args.put("marginBottom", marginBottom);
-        args.put("job", printJob.index);
-
-        channel.invokeMethod("onLayout", args, new Result() {
-            @Override
-            public void success(Object result) {
-                if (result instanceof byte[]) {
-                    printJob.setDocument((byte[]) result);
-                } else {
-                    printJob.cancelJob();
+        if (activity != null) {
+            handler = new PrintingHandler(activity, channel);
+            channel.setMethodCallHandler(handler);
         }
     }
 
     @Override
-            public void error(String errorCode, String errorMessage, Object errorDetails) {
-                printJob.cancelJob();
+    public void onDetachedFromEngine(FlutterPluginBinding binding) {
+        channel.setMethodCallHandler(null);
+        channel = null;
+        handler = null;
     }
 
     @Override
-            public void notImplemented() {
-                printJob.cancelJob();
+    public void onAttachedToActivity(ActivityPluginBinding binding) {
+        onAttachedToActivity(binding.getActivity());
     }
-        });
-    }
-
-    /// send completion status to flutter
-    void onCompleted(PrintingJob printJob, boolean completed, String error) {
-        HashMap<String, Object> args = new HashMap<>();
-        args.put("completed", completed);
 
-        args.put("error", error);
-        args.put("job", printJob.index);
+    private void onAttachedToActivity(Activity _activity) {
+        activity = _activity;
 
-        channel.invokeMethod("onCompleted", args);
+        if (activity != null && channel != null) {
+            handler = new PrintingHandler(activity, channel);
+            channel.setMethodCallHandler(handler);
         }
-
-    /// send html to pdf data result to flutter
-    void onHtmlRendered(PrintingJob printJob, byte[] pdfData) {
-        HashMap<String, Object> args = new HashMap<>();
-        args.put("doc", pdfData);
-        args.put("job", printJob.index);
-
-        channel.invokeMethod("onHtmlRendered", args);
     }
 
-    /// send html to pdf conversion error to flutter
-    void onHtmlError(PrintingJob printJob, String error) {
-        HashMap<String, Object> args = new HashMap<>();
-        args.put("error", error);
-        args.put("job", printJob.index);
-
-        channel.invokeMethod("onHtmlError", args);
+    @Override
+    public void onDetachedFromActivityForConfigChanges() {
+        onDetachedFromActivity();
     }
 
-    /// send pdf to raster data result to flutter
-    void onPageRasterized(PrintingJob printJob, byte[] imageData, int width, int height) {
-        HashMap<String, Object> args = new HashMap<>();
-        args.put("image", imageData);
-        args.put("width", width);
-        args.put("height", height);
-        args.put("job", printJob.index);
-
-        channel.invokeMethod("onPageRasterized", args);
+    @Override
+    public void onReattachedToActivityForConfigChanges(ActivityPluginBinding binding) {
+        onAttachedToActivity(binding.getActivity());
     }
 
-    void onPageRasterEnd(PrintingJob printJob) {
-        HashMap<String, Object> args = new HashMap<>();
-        args.put("job", printJob.index);
-
-        channel.invokeMethod("onPageRasterEnd", args);
+    @Override
+    public void onDetachedFromActivity() {
+        channel.setMethodCallHandler(null);
+        activity = null;
+        handler = null;
     }
 }

@@ -4,7 +4,7 @@ description: Plugin that allows Flutter apps to generate and print documents to
 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: 3.0.2
+version: 3.1.0
 
 environment:
   sdk: ">=2.3.0 <3.0.0"