Refactor Bluetooth settings for readability and performance.

Major refactoring of Bluetooth settings classes.
- Moved all functionality from LocalBluetoothManager into new
  LocalBluetoothAdapter and LocalBluetoothPreferences, and into
  existing classes.
- Refactored functionality from BluetoothEventRedirector into new
  BluetoothEventManager class, deleting the original version. New
  version uses a HashMap from action Strings to implementers of the
  BluetoothEventManager.Handler interface.
- Created new BluetoothDiscoveryReceiver to update shared preferences
  timestamp for Bluetooth discovery start/finish. This is the only event
  handling we need to do when the settings app is not visible, so it has
  its own receiver entry in AndroidManifest.xml. Edits are written using
  QueuedWork.singleThreadExecutor(), which BroadcastReceiver knows about
  and will wait for completion, eliminating the need for PendingResult.
- Miscellaneous cleanups to code style and logic for readability.
- Pulled some large switch statement code blocks into new methods.
- Changed all Bluetooth state references to the new BluetoothProfile
  constants.
- Changed use of deprecated Notification constructor in
  BluetoothPairingRequest to use Notification.Builder.
- Moved Utf8ByteLengthFilter helper function from BluetoothNamePreference
  into its own class, and moved test cases into the same package.
- Moved all LocalBluetoothProfileManager functionality related to
  specific profiles into new top-level classes (A2dpProfile, etc.), all
  implementing the LocalBluetoothProfile interface.
- Moved all UI-related methods from CachedBluetoothDevice into the class
  that uses the method, or into the static Utils class for shared methods.

Change-Id: I6d49b7f4ae0c7d7dcf62551ee40b51ecb5fe4f47

src/com/android/settings/bluetooth/A2dpProfile.java

@@ -0,0 +1,166 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * 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.
+ */
+
+package com.android.settings.bluetooth;
+
+import android.bluetooth.BluetoothA2dp;
+import android.bluetooth.BluetoothAdapter;
+import android.bluetooth.BluetoothClass;
+import android.bluetooth.BluetoothDevice;
+import android.bluetooth.BluetoothProfile;
+import android.bluetooth.BluetoothUuid;
+import android.content.Context;
+import android.os.ParcelUuid;
+
+import com.android.settings.R;
+
+import java.util.List;
+
+/**
+ * A2dpProfile handles Bluetooth A2DP.
+ * TODO: add null checks around calls to mService object.
+ */
+final class A2dpProfile implements LocalBluetoothProfile {
+    private BluetoothA2dp mService;
+
+    static final ParcelUuid[] SINK_UUIDS = {
+        BluetoothUuid.AudioSink,
+        BluetoothUuid.AdvAudioDist,
+    };
+
+    static final String NAME = "A2DP";
+
+    // Order of this profile in device profiles list
+    private static final int ORDINAL = 1;
+
+    // These callbacks run on the main thread.
+    private final class A2dpServiceListener
+            implements BluetoothProfile.ServiceListener {
+
+        public void onServiceConnected(int profile, BluetoothProfile proxy) {
+            mService = (BluetoothA2dp) proxy;
+        }
+
+        public void onServiceDisconnected(int profile) {
+            mService = null;
+        }
+    }
+
+    A2dpProfile(Context context) {
+        BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter();
+        adapter.getProfileProxy(context, new A2dpServiceListener(),
+                BluetoothProfile.A2DP);
+    }
+
+    public boolean isConnectable() {
+        return true;
+    }
+
+    public boolean isAutoConnectable() {
+        return true;
+    }
+
+    private List<BluetoothDevice> getConnectedDevices() {
+        return mService.getDevicesMatchingConnectionStates(
+              new int[] {BluetoothProfile.STATE_CONNECTED,
+                         BluetoothProfile.STATE_CONNECTING,
+                         BluetoothProfile.STATE_DISCONNECTING});
+    }
+
+    public boolean connect(BluetoothDevice device) {
+        List<BluetoothDevice> sinks = getConnectedDevices();
+        if (sinks != null) {
+            for (BluetoothDevice sink : sinks) {
+                mService.disconnect(sink);
+            }
+        }
+        return mService.connect(device);
+    }
+
+    public boolean disconnect(BluetoothDevice device) {
+        return mService.disconnect(device);
+    }
+
+    public int getConnectionStatus(BluetoothDevice device) {
+        return mService.getConnectionState(device);
+    }
+
+    public boolean isPreferred(BluetoothDevice device) {
+        return mService.getPriority(device) > BluetoothProfile.PRIORITY_OFF;
+    }
+
+    public int getPreferred(BluetoothDevice device) {
+        return mService.getPriority(device);
+    }
+
+    public void setPreferred(BluetoothDevice device, boolean preferred) {
+        if (preferred) {
+            if (mService.getPriority(device) < BluetoothProfile.PRIORITY_ON) {
+                mService.setPriority(device, BluetoothProfile.PRIORITY_ON);
+            }
+        } else {
+            mService.setPriority(device, BluetoothProfile.PRIORITY_OFF);
+        }
+    }
+
+    boolean isA2dpPlaying() {
+        List<BluetoothDevice> sinks = mService.getConnectedDevices();
+        if (!sinks.isEmpty()) {
+            if (mService.isA2dpPlaying(sinks.get(0))) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    public boolean isProfileReady() {
+        return mService != null;
+    }
+
+    public String toString() {
+        return NAME;
+    }
+
+    public int getOrdinal() {
+        return ORDINAL;
+    }
+
+    public int getNameResource() {
+        return R.string.bluetooth_profile_a2dp;
+    }
+
+    public int getDisconnectResource() {
+        return R.string.bluetooth_disconnect_a2dp_profile;
+    }
+
+    public int getSummaryResourceForDevice(BluetoothDevice device) {
+        int state = mService.getConnectionState(device);
+        switch (state) {
+            case BluetoothProfile.STATE_DISCONNECTED:
+                return R.string.bluetooth_a2dp_profile_summary_use_for;
+
+            case BluetoothProfile.STATE_CONNECTED:
+                return R.string.bluetooth_a2dp_profile_summary_connected;
+
+            default:
+                return Utils.getConnectionStateSummary(state);
+        }
+    }
+
+    public int getDrawableResource(BluetoothClass btClass) {
+        return R.drawable.ic_bt_headphones_a2dp;
+    }
+}