android/src/main/java/id/kalanusa/flutter_zsdk/FlutterZsdkPlugin.java

@@ -18,6 +18,8 @@ import java.util.ArrayList;
 import java.util.Map;
 import java.util.Objects;
 
+import id.kalanusa.flutter_zsdk.bluetoothconnectionhandler.BluetoothConnectionHandler;
+import id.kalanusa.flutter_zsdk.bluetoothconnectionhandler.BluetoothConnectionHolder;
 import id.kalanusa.flutter_zsdk.bluetoothdiscoveryhandler.BluetoothDiscoveryHandler;
 import id.kalanusa.flutter_zsdk.bluetoothdiscoveryhandler.BluetoothPrinter;
 import io.flutter.Log;
@@ -34,7 +36,7 @@ import io.flutter.plugin.common.MethodChannel.Result;
 import io.flutter.plugin.common.PluginRegistry;
 
 /** FlutterZsdkPlugin */
-public class FlutterZsdkPlugin implements FlutterPlugin, MethodCallHandler, ActivityAware, PluginRegistry.RequestPermissionsResultListener {
+public class FlutterZsdkPlugin implements FlutterPlugin, MethodCallHandler, ActivityAware {
   /// The MethodChannel that will the communication between Flutter and native Android
   ///
   /// This local reference serves to register the plugin with the Flutter Engine and unregister it
@@ -49,6 +51,11 @@ public class FlutterZsdkPlugin implements FlutterPlugin, MethodCallHandler, Acti
   private DartExecutor dartExecutor;
   private BinaryMessenger binaryMessenger;
 
+  public BluetoothConnectionHolder bluetoothConnectionHolder;
+
+  public BluetoothConnectionHandler bluetoothConnectionHandler;
+
+
   @Override
   public void onAttachedToEngine(@NonNull FlutterPluginBinding flutterPluginBinding) {
     channel = new MethodChannel(flutterPluginBinding.getBinaryMessenger(), "flutter_zsdk");
@@ -62,7 +69,6 @@ public class FlutterZsdkPlugin implements FlutterPlugin, MethodCallHandler, Acti
   @Override
   public void onAttachedToActivity(@NonNull ActivityPluginBinding binding) {
     activity = binding.getActivity();
-    binding.addRequestPermissionsResultListener(this);
 
     new EventChannel(binaryMessenger, bluetoothDiscoveryEventChannel).setStreamHandler(new BluetoothDiscoveryHandler(context, activity));
   }
@@ -84,134 +90,24 @@ public class FlutterZsdkPlugin implements FlutterPlugin, MethodCallHandler, Acti
 
   @Override
   public void onMethodCall(@NonNull MethodCall call, @NonNull Result result) {
-    switch(call.method) {
-      case "findBluetoothPrinters":
-        findBluetoothPrinters();
-      case "getPlatformVersion":
-        Log.w("from native", "TEST");
-    }
-  }
+    Log.w("From Native (Android)", "ini di FLutterZsdkPlugin");
 
-  @Override
-  public void onDetachedFromEngine(@NonNull FlutterPluginBinding binding) {
-    channel.setMethodCallHandler(null);
-  }
-
-  @Override
-  public boolean onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
-    if (requestCode == 1001) { // Check if it'sthe request we initiated
-      if (grantResults.length > 0) {
-        boolean bluetoothScanGranted = grantResults[0] == PackageManager.PERMISSION_GRANTED;
-        boolean bluetoothConnectGranted = grantResults[1] == PackageManager.PERMISSION_GRANTED;
-        boolean locationGranted = grantResults[2] == PackageManager.PERMISSION_GRANTED;
-
-        if (bluetoothScanGranted && bluetoothConnectGranted && locationGranted) {
-          // All permissions granted, proceed with Bluetooth operations
-          // ... your Bluetooth code here ...
-          this.startDiscoverBluetoothPrinters();
-        } else {
-          System.out.println("Permission Denied, please allow permission to discover bluetooth devices");
-          // Handle denied permissions
-          // You might display a messageto the user or disable Bluetooth features
-          // ... your logic for handling denied permissions ...
+    switch(call.method) {
+      case "bluetoothOpenConnection":
+      case "isConnected":
+      case "bluetoothCloseConnection":
+        if (bluetoothConnectionHandler == null) {
+          bluetoothConnectionHandler = new BluetoothConnectionHandler(bluetoothConnectionHolder);
         }
-      }
-    }
-
-    return true;
-  }
 
+        bluetoothConnectionHandler.handle(call, result);
+        break;
 
-//  Bluetooth discovery
-  public void findBluetoothPrinters() {
-    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
-      if (context.checkSelfPermission(Manifest.permission.BLUETOOTH_SCAN) != PackageManager.PERMISSION_GRANTED ||
-              context.checkSelfPermission(Manifest.permission.BLUETOOTH_CONNECT) != PackageManager.PERMISSION_GRANTED ||
-              context.checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
-
-        activity.requestPermissions(new String[]{
-                Manifest.permission.BLUETOOTH_SCAN,
-                Manifest.permission.BLUETOOTH_CONNECT,
-                Manifest.permission.ACCESS_FINE_LOCATION
-        }, 1001);
-      } else {
-        this.startDiscoverBluetoothPrinters();
-      }
-    } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
-      if (context.checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
-        activity.requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1002);
-      } else {
-        this.startDiscoverBluetoothPrinters();
-      }
     }
   }
 
-  public void startDiscoverBluetoothPrinters() {
-    new EventChannel(dartExecutor, bluetoothDiscoveryEventChannel).setStreamHandler(
-            new EventChannel.StreamHandler() {
-
-              @Override
-              public void onListen(Object arguments, EventChannel.EventSink events) {
-                Log.w("From native", "Adding Listener");
-                attachEvent = events;
-                handler = new Handler();
-                startDiscoverBluetoothPrintersRunnable.run();
-              }
-
-              @Override
-              public void onCancel(Object arguments) {
-                Log.w("From native", "Cancelling Listener");
-                handler.removeCallbacks(startDiscoverBluetoothPrintersRunnable);
-                handler = null;
-                attachEvent = null;
-                System.out.println("StreamHandler - onCanceled: ");              }
-            }
-    );
+  @Override
+  public void onDetachedFromEngine(@NonNull FlutterPluginBinding binding) {
+    channel.setMethodCallHandler(null);
   }
-
-//  public void startDiscoverBluetoothPrintersRunnable() {
-//    new Thread(new Runnable() {
-//      @Override
-//      public void run() {
-//
-//    });
-//  }
-//
-  private final Runnable startDiscoverBluetoothPrintersRunnable = new Runnable() {
-    @Override
-    public void run() {
-      ArrayList<BluetoothPrinter> tempDiscoveredPrinterList = new ArrayList<BluetoothPrinter>();
-      DiscoveryHandler discoveryHandler = new DiscoveryHandler() {
-        @Override
-        public void foundPrinter(DiscoveredPrinter discoveredPrinter) {
-          Map<String, String> discoveredPrinterDataMap = discoveredPrinter.getDiscoveryDataMap();
-          System.out.println("Found printer "  + discoveredPrinterDataMap.get("FRIENDLY_NAME"));
-
-          BluetoothPrinter bluetoothPrinter = new BluetoothPrinter(discoveredPrinterDataMap.get("FRIENDLY_NAME"), discoveredPrinterDataMap.get("MAC_ADDRESS"));
-          tempDiscoveredPrinterList.add(bluetoothPrinter);
-          attachEvent.success(tempDiscoveredPrinterList);
-        }
-
-        @Override
-        public void discoveryFinished() {
-          // return value here, this is asynchronous
-          Log.w("From Native", "Discovery Success, found "+ tempDiscoveredPrinterList.size() + " Printer(s)");
-          attachEvent.endOfStream();
-        }
-
-        @Override
-        public void discoveryError(String s) {
-          System.out.println("Error when discovering bluetooth device");
-          System.out.println("message:" + s);
-        }
-      };
-
-      try {
-        BluetoothDiscoverer.findPrinters(context, discoveryHandler);
-      } catch (ConnectionException e) {
-        System.out.println("Error when finding printers");
-//            throw new RuntimeException(e);
-      }
-    }
-  };
 }

android/src/main/java/id/kalanusa/flutter_zsdk/bluetoothconnectionhandler/BluetoothConnectionHandler.java

@@ -0,0 +1,91 @@
+package id.kalanusa.flutter_zsdk.bluetoothconnectionhandler;
+
+import android.os.Looper;
+
+import androidx.annotation.NonNull;
+
+import com.zebra.sdk.comm.BluetoothConnectionInsecure;
+import com.zebra.sdk.comm.Connection;
+import com.zebra.sdk.comm.ConnectionException;
+
+import io.flutter.Log;
+import io.flutter.plugin.common.MethodCall;
+import io.flutter.plugin.common.MethodChannel;
+
+public class BluetoothConnectionHandler {
+    BluetoothConnectionHolder bluetoothConnectionHolder;
+    String macAddress;
+
+    public BluetoothConnectionHandler(BluetoothConnectionHolder bluetoothConnectionHolder) {
+        this.bluetoothConnectionHolder = bluetoothConnectionHolder;
+    }
+
+    public void handle(@NonNull MethodCall call, @NonNull MethodChannel.Result result) {
+
+        switch (call.method) {
+            case "bluetoothOpenConnection":
+                if (bluetoothConnectionHolder == null) {
+                    bluetoothConnectionHolder = new BluetoothConnectionHolder(new BluetoothConnectionInsecure(call.argument("macAddress")));
+                }
+
+                openConnection(result);
+                break;
+
+            case "isConnected":
+                checkConnection(result);
+                break;
+
+            case "bluetoothCloseConnection":
+                closeConnection(result);
+                break;
+        }
+    }
+
+    public void openConnection(@NonNull MethodChannel.Result result) {
+        new Thread(new Runnable() {
+            @Override
+            public void run() {
+                try {
+                    Looper.prepare();
+                    bluetoothConnectionHolder.connection.open();
+                    Looper.myLooper().quit();
+                    result.success(null);
+                    Log.w("From Native (Android)", "open connection finished");
+                } catch (ConnectionException e) {
+                    Log.w("From Native (Android)", "Connection Exception threw " + e);
+                    result.error("OPEN_CONNECTION_ERROR", "Cant Connect to printers", e.getMessage());
+                }
+            }
+        }).start();
+    }
+
+    public void checkConnection(@NonNull MethodChannel.Result result) {
+        new Thread(new Runnable() {
+            @Override
+            public void run() {
+                boolean isConnected = bluetoothConnectionHolder.connection.isConnected();
+
+                result.success(isConnected);
+
+                Log.w("From Native (Android)", "isConnected: " + isConnected);
+            }
+        }).start();
+    }
+
+    public void closeConnection(@NonNull MethodChannel.Result result) {
+        new Thread(new Runnable() {
+            @Override
+            public void run() {
+                try {
+                    bluetoothConnectionHolder.connection.close();
+                    result.success(null);
+                } catch (ConnectionException e) {
+                    Log.w("From Native (Android)", "something went wrong when closing connection");
+                    result.error("CLOSE_CONNECTION_ERROR", "Something went wrong while closing the connection", e.getMessage());
+                }
+            }
+        }).start();
+    }
+
+
+}

android/src/main/java/id/kalanusa/flutter_zsdk/bluetoothconnectionhandler/BluetoothConnectionHolder.java

@@ -0,0 +1,17 @@
+package id.kalanusa.flutter_zsdk.bluetoothconnectionhandler;
+
+import androidx.annotation.NonNull;
+
+import com.zebra.sdk.comm.Connection;
+
+public class BluetoothConnectionHolder {
+    public Connection connection;
+
+    public BluetoothConnectionHolder(@NonNull Connection connection) {
+        this.connection = connection;
+    }
+
+    public void updateConnection(@NonNull Connection connection) {
+        this.connection = connection;
+    }
+}

example/lib/main.dart

@@ -23,36 +23,38 @@ class MyApp extends StatefulWidget {
 class _MyAppState extends State<MyApp> {
   bool _isDiscovering = false;
   List<BluetoothPrinter> _discoveredBluetoothPrinters = [];
-  String _platformVersion = 'Unknown';
+  String? _connectedPrinter;
   final _flutterZsdkPlugin = FlutterZsdk();
+  String? _selectedBluetoothPrinterMacAddress;
+  bool _disconnecting = false;
 
   @override
   void initState() {
     super.initState();
-    initPlatformState();
+    // initPlatformState();
   }
 
   // Platform messages are asynchronous, so we initialize in an async method.
-  Future<void> initPlatformState() async {
-    String platformVersion;
-    // Platform messages may fail, so we use a try/catch PlatformException.
-    // We also handle the message potentially returning null.
-    try {
-      platformVersion =
-          await _flutterZsdkPlugin.getPlatformVersion() ?? 'Unknown platform version';
-    } on PlatformException {
-      platformVersion = 'Failed to get platform version.';
-    }
-
-    // If the widget was removed from the tree while the asynchronous platform
-    // message was in flight, we want to discard the reply rather than calling
-    // setState to update our non-existent appearance.
-    if (!mounted) return;
-
-    setState(() {
-      _platformVersion = platformVersion;
-    });
-  }
+  // Future<void> initPlatformState() async {
+  //   String platformVersion;
+  //   // Platform messages may fail, so we use a try/catch PlatformException.
+  //   // We also handle the message potentially returning null.
+  //   try {
+  //     platformVersion =
+  //         await _flutterZsdkPlugin.getPlatformVersion() ?? 'Unknown platform version';
+  //   } on PlatformException {
+  //     platformVersion = 'Failed to get platform version.';
+  //   }
+
+  //   // If the widget was removed from the tree while the asynchronous platform
+  //   // message was in flight, we want to discard the reply rather than calling
+  //   // setState to update our non-existent appearance.
+  //   if (!mounted) return;
+
+  //   setState(() {
+  //     _platformVersion = platformVersion;
+  //   });
+  // }
 
   StreamSubscription? _bluetoothPrinterSubscription;
 
@@ -107,6 +109,48 @@ class _MyAppState extends State<MyApp> {
     }
   }
 
+  Future<void> openConnection() async {
+    print('invoked openConnection from dart');
+    try {
+      await _flutterZsdkPlugin.openConnection(_selectedBluetoothPrinterMacAddress ?? ''); 
+      _connectedPrinter = _selectedBluetoothPrinterMacAddress ?? 'Unknown printer';
+      print('Connection opened successfully from dart');
+      
+    } on FlutterZsdkException catch (e) {
+      inspect(e);
+      showSnackBar(e.message);
+
+    } catch (e) {
+      inspect(e);
+      showSnackBar('Unexpected error while connecting to bluetooth printers');
+    }
+
+    setState(() {});
+  }
+
+  Future<void> closeConnection() async {
+    print('invoked closeConnection from dart');
+    try {
+      setState(() {
+        _disconnecting = true;
+      });
+      await _flutterZsdkPlugin.closeConnection(); 
+      _connectedPrinter = null;
+      _disconnecting = false;
+      print('Connection closed successfully from dart');
+      
+    } on FlutterZsdkException catch (e) {
+      inspect(e);
+      showSnackBar(e.message);
+
+    } catch (e) {
+      inspect(e);
+      showSnackBar('Unexpected error while disconnecting bluetooth printers');
+    }
+
+    setState(() {});
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -118,9 +162,32 @@ class _MyAppState extends State<MyApp> {
           crossAxisAlignment: CrossAxisAlignment.center,
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
-            Text('Running on: $_platformVersion\n'),
+            Text('Connected printer: ${_connectedPrinter ?? "Unknown printer"}\n'),
+            Text('Selected printer Mac Address: $_selectedBluetoothPrinterMacAddress\n'),
             SizedBox(height: 20),
         
+            ElevatedButton(
+              child: Text('Connect to $_selectedBluetoothPrinterMacAddress'),
+              onPressed: _selectedBluetoothPrinterMacAddress == null || _connectedPrinter != null ? null : openConnection,
+            ),
+            SizedBox(height: 20),
+
+            ElevatedButton(
+              child: Text(_disconnecting ? 'Disconnecting...' : 'Disconnect from $_connectedPrinter'),
+              onPressed: _connectedPrinter == null || _disconnecting ? null : closeConnection,
+            ),
+            SizedBox(height: 20),
+
+            ElevatedButton(
+              child: Text('Check connection status'),
+              onPressed: () async {
+                bool isConnected =await _flutterZsdkPlugin.isConnected();
+              
+                print('isConnected from dart: $isConnected');
+              },
+            ),
+            SizedBox(height: 20),
+            
             ElevatedButton(
               child: Text(_isDiscovering ? 'Discovering bluetooth printers...' : 'Discover nearby bluetooth printers'),
               onPressed: _isDiscovering ? null : () async {
@@ -130,9 +197,20 @@ class _MyAppState extends State<MyApp> {
             SizedBox(height: 20),
 
             for (var printer in _discoveredBluetoothPrinters) ... [
-              Text(printer.friendlyName),
-              Text(printer.macAddress),
-              SizedBox(height: 10)
+              InkWell(
+                onTap: () {
+                  _selectedBluetoothPrinterMacAddress = printer.macAddress;
+                  setState(() {});
+                },
+                child: Column(
+                  mainAxisSize: MainAxisSize.min,
+                  children: [
+                    Text(printer.friendlyName),
+                    Text(printer.macAddress),
+                    SizedBox(height: 10)
+                  ],
+                ),
+              )
             ]
           ] 
           

lib/flutter_zsdk.dart

@@ -11,4 +11,17 @@ class FlutterZsdk {
   Future<Stream<dynamic>> findBluetoothPrinters() {
     return FlutterZsdkPlatform.instance.findBluetoothPrinters();
   }
+
+  Future<void> openConnection(String macAddress) {
+    return FlutterZsdkPlatform.instance.openConnection(macAddress);
+  }
+
+  /// this api must not be called before FlutterZsdkPlugin.openConnection()
+  Future<bool> isConnected() {
+    return FlutterZsdkPlatform.instance.isConnected();
+  }
+
+  Future<void> closeConnection() {
+    return FlutterZsdkPlatform.instance.closeConnection();
+  }
 }

lib/src/flutter_zsdk_method_channel.dart

@@ -1,5 +1,7 @@
 import 'dart:async';
+import 'dart:developer';
 import 'dart:io';
+import 'dart:math';
 
 import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
@@ -81,4 +83,34 @@ class MethodChannelFlutterZsdk extends FlutterZsdkPlatform {
     }
     
   }
+
+  @override
+  Future<void> openConnection(String macAddress) async {
+    try {
+      await methodChannel.invokeMethod('bluetoothOpenConnection', {'macAddress': macAddress});
+
+    } on PlatformException catch (e) {
+      inspect(e);
+      throw FlutterZsdkException("Failed to open connection to printer: ${e.details}");
+
+    } catch (e) {
+      throw FlutterZsdkException("Failed to open connection to printer: $e");
+    }
+  }
+
+  @override
+  Future<bool> isConnected() async {
+    bool isConnected = await methodChannel.invokeMethod('isConnected');
+
+    return isConnected;
+  }
+
+  @override
+  Future<void> closeConnection() async {
+    try {
+      await methodChannel.invokeMethod('bluetoothCloseConnection');
+    } catch (e) {
+      throw FlutterZsdkException("Failed to close connection to printer: $e");
+    }
+  }
 }

lib/src/flutter_zsdk_platform_interface.dart

@@ -31,4 +31,16 @@ abstract class FlutterZsdkPlatform extends PlatformInterface {
   Future<Stream<dynamic>> findBluetoothPrinters() {
     throw UnimplementedError('findBluetoothPrinters() has not been implemented.');
   }
+
+  Future<void> openConnection(String macAddress) {
+    throw UnimplementedError('openConnection() has not been implemented.');
+  }
+
+  Future<bool> isConnected() {
+    throw UnimplementedError('isConnected() has not been implemented.');
+  }
+
+  Future<void> closeConnection() {
+    throw UnimplementedError('closeConnection() has not been implemented.');
+  }
 }