Add an API call to get the ConnectionState of the Bluetooth Adapter.

Change-Id: Icd87d7720189034946aaa98e1a6c5d03ef4219e5

core/java/android/bluetooth/BluetoothAdapter.java

@@ -737,6 +737,27 @@ public final class BluetoothAdapter {
         return null;
     }
 
+    /**
+     * Get the current connection state of the local Bluetooth adapter.
+     * This can be used to check whether the local Bluetooth adapter is connected
+     * to any profile of any other remote Bluetooth Device.
+     *
+     * <p> Use this function along with {@link #ACTION_CONNECTION_STATE_CHANGED}
+     * intent to get the connection state of the adapter.
+     *
+     * @return One of {@link #STATE_CONNECTED}, {@link #STATE_DISCONNECTED},
+     * {@link #STATE_CONNECTING} or {@link #STATE_DISCONNECTED}
+     *
+     * @hide
+     */
+    public int getConnectionState() {
+        if (getState() != STATE_ON) return BluetoothAdapter.STATE_DISCONNECTED;
+        try {
+            return mService.getAdapterConnectionState();
+        } catch (RemoteException e) {Log.e(TAG, "getConnectionState:", e);}
+        return BluetoothAdapter.STATE_DISCONNECTED;
+    }
+
     /**
      * Picks RFCOMM channels until none are left.
      * Avoids reserved channels.
@@ -879,6 +900,7 @@ public final class BluetoothAdapter {
         return socket;
     }
 
+
     /**
      * Construct an unencrypted, unauthenticated, RFCOMM server socket.
      * Call #accept to retrieve connections to this socket.

core/java/android/bluetooth/IBluetooth.aidl

@@ -47,6 +47,8 @@ interface IBluetooth
     boolean isDiscovering();
     byte[] readOutOfBandData();
 
+    int getAdapterConnectionState();
+
     boolean createBond(in String address);
     boolean createBondOutOfBand(in String address, in byte[] hash, in byte[] randomizer);
     boolean cancelBondProcess(in String address);

core/java/android/server/BluetoothService.java

@@ -167,6 +167,8 @@ public class BluetoothService extends IBluetooth.Stub {
     private static String mDockAddress;
     private String mDockPin;
 
+    private int mAdapterConnectionState = BluetoothAdapter.STATE_DISCONNECTED;
+
     private static class RemoteService {
         public String address;
         public ParcelUuid uuid;
@@ -415,6 +417,7 @@ public class BluetoothService extends IBluetooth.Stub {
         mProfilesConnected = 0;
         mProfilesConnecting = 0;
         mProfilesDisconnecting = 0;
+        mAdapterConnectionState = BluetoothAdapter.STATE_DISCONNECTED;
 
         if (saveSetting) {
             persistBluetoothOnSetting(false);
@@ -2737,11 +2740,18 @@ public class BluetoothService extends IBluetooth.Stub {
         }
     }
 
+    public int getAdapterConnectionState() {
+        return mAdapterConnectionState;
+    }
+
     public synchronized void sendConnectionStateChange(BluetoothDevice device, int state,
                                                         int prevState) {
         if (updateCountersAndCheckForConnectionStateChange(device, state, prevState)) {
-            state = getAdapterConnectionState(state);
-            prevState = getAdapterConnectionState(prevState);
+            state = translateToAdapterConnectionState(state);
+            prevState = translateToAdapterConnectionState(prevState);
+
+            mAdapterConnectionState = state;
+
             Intent intent = new Intent(BluetoothAdapter.ACTION_CONNECTION_STATE_CHANGED);
             intent.putExtra(BluetoothDevice.EXTRA_DEVICE, device);
             intent.putExtra(BluetoothAdapter.EXTRA_CONNECTION_STATE, state);
@@ -2751,7 +2761,7 @@ public class BluetoothService extends IBluetooth.Stub {
         }
     }
 
-    private int getAdapterConnectionState(int state) {
+    private int translateToAdapterConnectionState(int state) {
         switch (state) {
             case BluetoothProfile.STATE_CONNECTING:
                 return BluetoothAdapter.STATE_CONNECTING;