added mtu set to android api

examples/example-android/androidBleSdkTestApp/app/src/main/java/polar/com/androidblesdk/MainActivity.java

@@ -57,6 +57,7 @@ protected void onCreate(Bundle savedInstanceState) {
         // Notice PolarBleApi.ALL_FEATURES are enabled
         api = PolarBleApiDefaultImpl.defaultImplementation(this, PolarBleApi.ALL_FEATURES);
         api.setPolarFilter(false);
+        api.setMtu(140);
 
         final Button broadcast = this.findViewById(R.id.broadcast_button);
         final Button connect = this.findViewById(R.id.connect_button);

sources/Android/android-communications/src/main/java/com/androidcommunications/polar/api/ble/BleDeviceListener.java

@@ -2,6 +2,7 @@
 
 import android.bluetooth.le.ScanFilter;
 import android.support.annotation.IntDef;
+import android.support.annotation.IntRange;
 import android.support.annotation.Nullable;
 import android.util.Pair;
 
@@ -102,6 +103,8 @@ public interface BlePowerStateChangedCallback {
      */
     abstract public Flowable<BleDeviceSession> search(boolean fetchKnownDevices);
 
+    abstract public void setMtu(@IntRange(from = 70, to = 512) int mtu);
+
     /**
      * As java does not support destructor/RAII, Client/App should call this whenever the application is being destroyed
      */
@@ -123,9 +126,9 @@ public interface BlePowerStateChangedCallback {
     /**
      * Deprecated use setDeviceSessionStateChangedCallback instead
      *
-     * Produces: onNext: When a device session state has changed, Note use pair.second to check the state (see BleDeviceSession.DeviceSessionState)<BR>
-     *           onError: should not be produced<BR>
-     *           onCompleted: This is never propagated, NOTE to get completed event configure observable with some end rule e.g. take(1), takeUntil() etc...<BR>
+     * Produces: onNext: When a device session state has changed, Note use pair.second to check the state (see BleDeviceSession.DeviceSessionState) <BR>
+     *           onError: should not be produced <BR>
+     *           onCompleted: If stream is further configured <BR>
      * @param session, a specific session or null = monitor all sessions
      * @return Observable stream
      */
@@ -149,7 +152,7 @@ public interface BleDeviceSessionStateChangedCallback {
     abstract public void setDeviceSessionStateChangedCallback(@Nullable BleDeviceSessionStateChangedCallback changedCallback);
 
     /**
-     * aquires disconnection establishment directly without Observable returned
+     * aquires disconnection directly without Observable returned
      * @param session device
      */
     abstract public void closeSessionDirect(BleDeviceSession session);

sources/Android/android-communications/src/main/java/com/androidcommunications/polar/api/ble/model/gatt/client/BlePMDClient.java

@@ -167,7 +167,8 @@ public enum PmdControlPointResponseCode {
             ERROR_INVALID_STATE(6),
             ERROR_INVALID_RESOLUTION(7),
             ERROR_INVALID_SAMPLE_RATE(8),
-            ERROR_INVALID_RANGE(9);
+            ERROR_INVALID_RANGE(9),
+            ERROR_INVALID_MTU(10);
 
             private int numVal;
             PmdControlPointResponseCode(int numVal) {
@@ -183,9 +184,11 @@ public PmdControlPointResponse(byte[] data) {
             opCode = PmdControlPointCommand.values()[data[1]];
             measurementType = data[2];
             status = PmdControlPointResponseCode.values()[data[3]];
-            more = data.length > 4 && data[4] != 0;
-            if (data.length > 5) {
-                parameters.write(data, 5, data.length - 5);
+            if (status == PmdControlPointResponseCode.SUCCESS) {
+                more = data.length > 4 && data[4] != 0;
+                if (data.length > 5) {
+                    parameters.write(data, 5, data.length - 5);
+                }
             }
         }
     }

sources/Android/android-communications/src/main/java/com/androidcommunications/polar/enpoints/ble/bluedroid/host/BDDeviceListenerImpl.java

@@ -202,6 +202,11 @@ public void run() {
         });
     }
 
+    @Override
+    public void setMtu(int mtu) {
+        gattCallback.setPolarMaxMtu(mtu);
+    }
+
     @Override
     public void shutDown(){
         super.shutDown();

sources/Android/android-communications/src/main/java/com/androidcommunications/polar/enpoints/ble/bluedroid/host/BDGattCallback.java

@@ -26,7 +26,7 @@
 class BDGattCallback extends BluetoothGattCallback {
 
     private final static String TAG = BDGattCallback.class.getSimpleName();
-    private final static int POLAR_MAX_MTU = 512;
+    private int POLAR_MAX_MTU = 512;
 
     private ConnectionHandler connectionHandler;
     private BDDeviceList sessions;
@@ -38,6 +38,10 @@ class BDGattCallback extends BluetoothGattCallback {
         this.sessions = sessions;
     }
 
+    void setPolarMaxMtu(int mtu) {
+        POLAR_MAX_MTU = mtu;
+    }
+
     @Override
     public void onConnectionStateChange(final BluetoothGatt gatt, int status, int newState) {
         final BDDeviceSessionImpl smartPolarDeviceSession = sessions.getSession(gatt);

sources/Android/android-communications/src/main/java/com/androidcommunications/polar/enpoints/ble/common/BleDeviceListener2.java

@@ -1,6 +1,7 @@
 package com.androidcommunications.polar.enpoints.ble.common;
 
 import android.content.Context;
+import android.support.annotation.IntRange;
 import android.support.annotation.Nullable;
 import android.util.Pair;
 

sources/Android/android-communications/src/main/java/polar/com/sdk/api/PolarBleApi.java

@@ -1,6 +1,7 @@
 // Copyright © 2019 Polar Electro Oy. All rights reserved.
 package polar.com.sdk.api;
 
+import android.support.annotation.IntRange;
 import android.support.annotation.Nullable;
 import android.support.annotation.Size;
 import android.util.Pair;
@@ -103,6 +104,13 @@ protected PolarBleApi(final int features) {
         this.features = features;
     }
 
+    /**
+     * set mtu to lower than default(232 is the default for polar devices, minimum for H10 is 70 and for OH1 is 140)
+     * to minimize latency
+     * @param mtu value between 64-512 to be set
+     */
+    public abstract void setMtu(@IntRange(from = 70, to = 512) int mtu);
+
     /**
      * Must be called when application is destroyed.
      */

sources/Android/android-communications/src/main/java/polar/com/sdk/impl/BDBleApiImpl.java

@@ -165,6 +165,11 @@ protected void enableAndroidScanFilter() {
         }
     }
 
+    @Override
+    public void setMtu(int mtu) {
+        listener.setMtu(mtu);
+    }
+
     @Override
     public void shutDown() {
         listener.shutDown();