Java tutorial
/* * Copyright (C) 2016 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.github.w666.ezonwatch; import android.app.NotificationManager; import android.app.Service; import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.bluetooth.BluetoothGatt; import android.bluetooth.BluetoothGattCallback; import android.bluetooth.BluetoothGattCharacteristic; import android.bluetooth.BluetoothGattDescriptor; import android.bluetooth.BluetoothGattService; import android.bluetooth.BluetoothManager; import android.bluetooth.BluetoothProfile; import android.content.Context; import android.content.Intent; import android.os.Binder; import android.os.IBinder; import android.support.v4.app.NotificationCompat; import android.util.Log; import java.util.List; import java.util.UUID; /** * Service for managing connection and data communication with a GATT server hosted on a * given Bluetooth LE device. */ public class BluetoothLeService extends Service { private final static String TAG = BluetoothLeService.class.getSimpleName(); private BluetoothManager mBluetoothManager; private BluetoothAdapter mBluetoothAdapter; private String mBluetoothDeviceAddress; private BluetoothGatt mBluetoothGatt; private boolean isServicesDescovered = false; private int mConnectionState = STATE_DISCONNECTED; private static final int STATE_DISCONNECTED = 0; private static final int STATE_CONNECTING = 1; private static final int STATE_CONNECTED = 2; public final static String ACTION_GATT_CONNECTED = "com.example.bluetooth.le.ACTION_GATT_CONNECTED"; public final static String ACTION_GATT_DISCONNECTED = "com.example.bluetooth.le.ACTION_GATT_DISCONNECTED"; public final static String ACTION_GATT_SERVICES_DISCOVERED = "com.example.bluetooth.le.ACTION_GATT_SERVICES_DISCOVERED"; public final static String ACTION_DATA_AVAILABLE = "com.example.bluetooth.le.ACTION_DATA_AVAILABLE"; public final static String EXTRA_DATA = "com.example.bluetooth.le.EXTRA_DATA"; public final static UUID UUID_EZON_MAIN = UUID.fromString(SampleGattAttributes.EZON_CHARACTERISTIC); // Implements callback methods for GATT events that the app cares about. For example, // connection change and services discovered. protected final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() { @Override public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) { String intentAction; if (newState == BluetoothProfile.STATE_CONNECTED) { intentAction = ACTION_GATT_CONNECTED; mConnectionState = STATE_CONNECTED; broadcastUpdate(intentAction); Log.i(TAG, "Connected to GATT server."); // Attempts to discover services after successful connection. if (isServicesDescovered) { Log.i(TAG, "Services are already discovered"); } else { isServicesDescovered = mBluetoothGatt.discoverServices(); Log.i(TAG, "Attempting to start service discovery:" + isServicesDescovered); } } else if (newState == BluetoothProfile.STATE_DISCONNECTED) { intentAction = ACTION_GATT_DISCONNECTED; mConnectionState = STATE_DISCONNECTED; Log.i(TAG, "Disconnected from GATT server."); broadcastUpdate(intentAction); } } @Override public void onServicesDiscovered(BluetoothGatt gatt, int status) { if (status == BluetoothGatt.GATT_SUCCESS) { broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED); } else { Log.w(TAG, "onServicesDiscovered received: " + status); } } @Override public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) { if (status == BluetoothGatt.GATT_SUCCESS) { broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic); } } @Override public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) { if (status == BluetoothGatt.GATT_SUCCESS) { broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic); } } @Override public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) { broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic); } }; private void broadcastUpdate(final String action) { final Intent intent = new Intent(action); sendBroadcast(intent); } private void broadcastUpdate(final String action, final BluetoothGattCharacteristic characteristic) { final Intent intent = new Intent(action); // For all other profiles, writes the data formatted in HEX. final byte[] data = characteristic.getValue(); if (data != null && data.length > 0) { intent.putExtra(EXTRA_DATA, data); } sendBroadcast(intent); } public class LocalBinder extends Binder { BluetoothLeService getService() { return BluetoothLeService.this; } } @Override public IBinder onBind(Intent intent) { return mBinder; } @Override public boolean onUnbind(Intent intent) { // After using a given device, you should make sure that BluetoothGatt.close() is called // such that resources are cleaned up properly. In this particular example, close() is // invoked when the UI is disconnected from the Service. close(); return super.onUnbind(intent); } private final IBinder mBinder = new LocalBinder(); /** * Initializes a reference to the local Bluetooth adapter. * * @return Return true if the initialization is successful. */ public boolean initialize() { // For API level 18 and above, get a reference to BluetoothAdapter through // BluetoothManager. if (mBluetoothManager == null) { mBluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE); if (mBluetoothManager == null) { Log.e(TAG, "Unable to initialize BluetoothManager."); return false; } } mBluetoothAdapter = mBluetoothManager.getAdapter(); if (mBluetoothAdapter == null) { Log.e(TAG, "Unable to obtain a BluetoothAdapter."); return false; } return true; } /** * Connects to the GATT server hosted on the Bluetooth LE device. * * @param address The device address of the destination device. * * @return Return true if the connection is initiated successfully. The connection result * is reported asynchronously through the * {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)} * callback. */ public boolean connect(final String address) { if (mBluetoothAdapter == null || address == null) { Log.w(TAG, "BluetoothAdapter not initialized or unspecified address."); return false; } // Previously connected device. Try to reconnect. if (mBluetoothDeviceAddress != null && address.equals(mBluetoothDeviceAddress) && mBluetoothGatt != null) { Log.d(TAG, "Trying to use an existing mBluetoothGatt for connection."); if (mBluetoothGatt.connect()) { mConnectionState = STATE_CONNECTING; return true; } else { return false; } } final BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address); if (device == null) { Log.w(TAG, "Device not found. Unable to connect."); return false; } // We want to directly connect to the device, so we are setting the autoConnect // parameter to false. mBluetoothGatt = device.connectGatt(this, false, mGattCallback); Log.d(TAG, "Trying to create a new connection."); mBluetoothDeviceAddress = address; mConnectionState = STATE_CONNECTING; return true; } private void showNotification() { NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this) .setContentTitle("My notification").setContentText("Hello World!"); int mNotificationId = 001; NotificationManager mNotifyMgr = (NotificationManager) getSystemService(NOTIFICATION_SERVICE); mNotifyMgr.notify(mNotificationId, mBuilder.build()); } /** * Disconnects an existing connection or cancel a pending connection. The disconnection result * is reported asynchronously through the * {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)} * callback. */ public void disconnect() { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.disconnect(); } /** * After using a given BLE device, the app must call this method to ensure resources are * released properly. */ public void close() { if (mBluetoothGatt == null) { return; } mBluetoothGatt.close(); mBluetoothGatt = null; } /** * Request a read on a given {@code BluetoothGattCharacteristic}. The read result is reported * asynchronously through the {@code BluetoothGattCallback#onCharacteristicRead(android.bluetooth.BluetoothGatt, android.bluetooth.BluetoothGattCharacteristic, int)} * callback. * * @param characteristic The characteristic to read from. */ public void readCharacteristic(BluetoothGattCharacteristic characteristic) { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.readCharacteristic(characteristic); } public void writeCharacteristic(BluetoothGattCharacteristic characteristic) { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.writeCharacteristic(characteristic); } /** * Enables or disables notification on a give characteristic. * * @param characteristic Characteristic to act on. * @param enabled If true, enable notification. False otherwise. */ public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic, boolean enabled) { if (mBluetoothAdapter == null || mBluetoothGatt == null) { Log.w(TAG, "BluetoothAdapter not initialized"); return; } mBluetoothGatt.setCharacteristicNotification(characteristic, enabled); if (characteristic.getUuid().equals(UUID_EZON_MAIN)) { BluetoothGattDescriptor descriptor = characteristic .getDescriptor(UUID.fromString("00002902-0000-1000-8000-00805f9b34fb")); descriptor.setValue( enabled ? BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE : new byte[] { 0x00, 0x00 }); descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE); mBluetoothGatt.writeDescriptor(descriptor); } } /** * Retrieves a list of supported GATT services on the connected device. This should be * invoked only after {@code BluetoothGatt#discoverServices()} completes successfully. * * @return A {@code List} of supported services. */ public List<BluetoothGattService> getSupportedGattServices() { if (mBluetoothGatt == null) return null; return mBluetoothGatt.getServices(); } }