Android BLE与终端通信（三）——客户端与服务端通信过程以及实现数据通信
前面的终究只是小知识点，上不了台面，也只能算是起到一个科普的作用，而同步到实际的开发上去，今天就来延续前两篇实现蓝牙主从关系的客户端和服务端了，本文相关链接需要去google的API上查看，需要FQ的
Bluetooth Low Energy：http://developer.android.com/guide/topics/connectivity/bluetooth-le.html
但是我们依然没有讲到BLE(低功耗蓝牙)，放心，下一篇就回讲到，跟前面的基本上很大的不同，我们今天来看下客户端和服务端的实现
我们以上篇为栗子：
Android BLE与终端通信（二）——Android Bluetooth基础搜索蓝牙设备显示列表
一.蓝牙数据传输
蓝牙数据传输其实跟我们的 Socket（套接字）有点类似，如果有不懂的，可以百度一下概念，我们只要知道是这么回事就可以了，在网络中使用Socket和ServerSocket控制客户端和服务端来数据读写。而蓝牙通讯也是由客户端和服务端来完成的，蓝牙客户端Socket是BluetoothSocket,蓝牙服务端Socket是BluetoothServerSocket,这两个类都在android.bluetooth包下，而且无论是BluetoothSocket还是BluetoothServerSocket，我们都需要一个UUID（标识符），这个UUID在上篇也是有提到，而且他的格式也是固定的：
UUID:XXXXXXXX(8)-XXXX(4)-XXXX(4)-XXXX(4)-XXXXXXXXXXXX(12)
第一段是8位，中间三段式4位，最后一段是12位，UUID相当于Socket的端口，而蓝牙地址则相当于Socket的IP
1.activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="btnSearch"
android:text="搜索蓝牙设备" />
<ListView
android:id="@+id/lvDevices"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
</LinearLayout>2.实现步骤
1.声明
我们需要的东西
// 本地蓝牙适配器
private BluetoothAdapter mBluetoothAdapter;
// 列表
private ListView lvDevices;
// 存储搜索到的蓝牙
private List<String> bluetoothDevices = new ArrayList<String>();
// listview的adapter
private ArrayAdapter<String> arrayAdapter;
// UUID.randomUUID()随机获取UUID
private final UUID MY_UUID = UUID
.fromString("db764ac8-4b08-7f25-aafe-59d03c27bae3");
// 连接对象的名称
private final String NAME = "LGL";
// 这里本身即是服务端也是客户端，需要如下类
private BluetoothSocket clientSocket;
private BluetoothDevice device;
// 输出流_客户端需要往服务端输出
private OutputStream os;2.初始化
// 获取本地蓝牙适配器
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
// 判断手机是否支持蓝牙
if (mBluetoothAdapter == null) {
Toast.makeText(this, "设备不支持蓝牙", Toast.LENGTH_SHORT).show();
finish();
}
// 判断是否打开蓝牙
if (!mBluetoothAdapter.isEnabled()) {
// 弹出对话框提示用户是后打开
Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent, 1);
// 不做提示，强行打开
// mBluetoothAdapter.enable();
}
// 初始化listview
lvDevices = (ListView) findViewById(R.id.lvDevices);
lvDevices.setOnItemClickListener(this);
// 获取已经配对的设备
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter
.getBondedDevices();
// 判断是否有配对过的设备
if (pairedDevices.size() > 0) {
for (BluetoothDevice device : pairedDevices) {
// 遍历到列表中
bluetoothDevices.add(device.getName() + ":"
+ device.getAddress() + "\n");
}
}
// adapter
arrayAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1,
bluetoothDevices);
lvDevices.setAdapter(arrayAdapter);
/**
* 异步搜索蓝牙设备——广播接收
*/
// 找到设备的广播
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
// 注册广播
registerReceiver(receiver, filter);
// 搜索完成的广播
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
// 注册广播
registerReceiver(receiver, filter);
}3.点击搜索
public void btnSearch(View v) {
// 设置进度条
setProgressBarIndeterminateVisibility(true);
setTitle("正在搜索...");
// 判断是否在搜索,如果在搜索，就取消搜索
if (mBluetoothAdapter.isDiscovering()) {
mBluetoothAdapter.cancelDiscovery();
}
// 开始搜索
mBluetoothAdapter.startDiscovery();
}4.搜索设备
private final BroadcastReceiver receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
// 收到的广播类型
String action = intent.getAction();
// 发现设备的广播
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
// 从intent中获取设备
BluetoothDevice device = intent
.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
// 判断是否配对过
if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
// 添加到列表
bluetoothDevices.add(device.getName() + ":"
+ device.getAddress() + "\n");
arrayAdapter.notifyDataSetChanged();
}
// 搜索完成
} else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED
.equals(action)) {
// 关闭进度条
setProgressBarIndeterminateVisibility(true);
setTitle("搜索完成！");
}
}
};5.客户端实现已经发送数据流
// 客户端
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
// 先获得蓝牙的地址和设备名
String s = arrayAdapter.getItem(position);
// 单独解析地址
String address = s.substring(s.indexOf(":") + 1).trim();
// 主动连接蓝牙
try {
// 判断是否在搜索,如果在搜索，就取消搜索
if (mBluetoothAdapter.isDiscovering()) {
mBluetoothAdapter.cancelDiscovery();
}
try {
// 判断是否可以获得
if (device == null) {
// 获得远程设备
device = mBluetoothAdapter.getRemoteDevice(address);
}
// 开始连接
if (clientSocket == null) {
clientSocket = device
.createRfcommSocketToServiceRecord(MY_UUID);
// 连接
clientSocket.connect();
// 获得输出流
os = clientSocket.getOutputStream();
}
} catch (Exception e) {
// TODO: handle exception
}
// 如果成功获得输出流
if (os != null) {
os.write("Hello Bluetooth!".getBytes("utf-8"));
}
} catch (Exception e) {
// TODO: handle exception
}
}
6.Handler服务
// 服务端，需要监听客户端的线程类
private Handler handler = new Handler() {
public void handleMessage(android.os.Message msg) {
Toast.makeText(MainActivity.this, String.valueOf(msg.obj),
Toast.LENGTH_SHORT).show();
super.handleMessage(msg);
}
};7.服务端读取数据流
// 线程服务类
private class AcceptThread extends Thread {
private BluetoothServerSocket serverSocket;
private BluetoothSocket socket;
// 输入 输出流
private OutputStream os;
private InputStream is;
public AcceptThread() {
try {
serverSocket = mBluetoothAdapter
.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
public void run() {
// 截获客户端的蓝牙消息
try {
socket = serverSocket.accept(); // 如果阻塞了，就会一直停留在这里
is = socket.getInputStream();
os = socket.getOutputStream();
// 不断接收请求,如果客户端没有发送的话还是会阻塞
while (true) {
// 每次只发送128个字节
byte[] buffer = new byte[128];
// 读取
int count = is.read();
// 如果读取到了，我们就发送刚才的那个Toast
Message msg = new Message();
msg.obj = new String(buffer, 0, count, "utf-8");
handler.sendMessage(msg);
}
} catch (Exception e) {
// TODO: handle exception
}
}
}8.开启服务
首先要声明
//启动服务
ac = new AcceptThread();
ac.start();MainActivity完整代码
package com.lgl.bluetoothget;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.UUID;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity implements OnItemClickListener {
// 本地蓝牙适配器
private BluetoothAdapter mBluetoothAdapter;
// 列表
private ListView lvDevices;
// 存储搜索到的蓝牙
private List<String> bluetoothDevices = new ArrayList<String>();
// listview的adapter
private ArrayAdapter<String> arrayAdapter;
// UUID.randomUUID()随机获取UUID
private final UUID MY_UUID = UUID
.fromString("db764ac8-4b08-7f25-aafe-59d03c27bae3");
// 连接对象的名称
private final String NAME = "LGL";
// 这里本身即是服务端也是客户端，需要如下类
private BluetoothSocket clientSocket;
private BluetoothDevice device;
// 输出流_客户端需要往服务端输出
private OutputStream os;
//线程类的实例
private AcceptThread ac;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}
private void initView() {
// 获取本地蓝牙适配器
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
// 判断手机是否支持蓝牙
if (mBluetoothAdapter == null) {
Toast.makeText(this, "设备不支持蓝牙", Toast.LENGTH_SHORT).show();
finish();
}
// 判断是否打开蓝牙
if (!mBluetoothAdapter.isEnabled()) {
// 弹出对话框提示用户是后打开
Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent, 1);
// 不做提示，强行打开
// mBluetoothAdapter.enable();
}
// 初始化listview
lvDevices = (ListView) findViewById(R.id.lvDevices);
lvDevices.setOnItemClickListener(this);
// 获取已经配对的设备
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter
.getBondedDevices();
// 判断是否有配对过的设备
if (pairedDevices.size() > 0) {
for (BluetoothDevice device : pairedDevices) {
// 遍历到列表中
bluetoothDevices.add(device.getName() + ":"
+ device.getAddress() + "\n");
}
}
// adapter
arrayAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1,
bluetoothDevices);
lvDevices.setAdapter(arrayAdapter);
//启动服务
ac = new AcceptThread();
ac.start();
/**
* 异步搜索蓝牙设备——广播接收
*/
// 找到设备的广播
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
// 注册广播
registerReceiver(receiver, filter);
// 搜索完成的广播
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
// 注册广播
registerReceiver(receiver, filter);
}
public void btnSearch(View v) {
// 设置进度条
setProgressBarIndeterminateVisibility(true);
setTitle("正在搜索...");
// 判断是否在搜索,如果在搜索，就取消搜索
if (mBluetoothAdapter.isDiscovering()) {
mBluetoothAdapter.cancelDiscovery();
}
// 开始搜索
mBluetoothAdapter.startDiscovery();
}
// 广播接收器
private final BroadcastReceiver receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
// 收到的广播类型
String action = intent.getAction();
// 发现设备的广播
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
// 从intent中获取设备
BluetoothDevice device = intent
.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
// 判断是否配对过
if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
// 添加到列表
bluetoothDevices.add(device.getName() + ":"
+ device.getAddress() + "\n");
arrayAdapter.notifyDataSetChanged();
}
// 搜索完成
} else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED
.equals(action)) {
// 关闭进度条
setProgressBarIndeterminateVisibility(true);
setTitle("搜索完成！");
}
}
};
// 客户端
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
// 先获得蓝牙的地址和设备名
String s = arrayAdapter.getItem(position);
// 单独解析地址
String address = s.substring(s.indexOf(":") + 1).trim();
// 主动连接蓝牙
try {
// 判断是否在搜索,如果在搜索，就取消搜索
if (mBluetoothAdapter.isDiscovering()) {
mBluetoothAdapter.cancelDiscovery();
}
try {
// 判断是否可以获得
if (device == null) {
// 获得远程设备
device = mBluetoothAdapter.getRemoteDevice(address);
}
// 开始连接
if (clientSocket == null) {
clientSocket = device
.createRfcommSocketToServiceRecord(MY_UUID);
// 连接
clientSocket.connect();
// 获得输出流
os = clientSocket.getOutputStream();
}
} catch (Exception e) {
// TODO: handle exception
}
// 如果成功获得输出流
if (os != null) {
os.write("Hello Bluetooth!".getBytes("utf-8"));
}
} catch (Exception e) {
// TODO: handle exception
}
}
// 服务端，需要监听客户端的线程类
private Handler handler = new Handler() {
public void handleMessage(android.os.Message msg) {
Toast.makeText(MainActivity.this, String.valueOf(msg.obj),
Toast.LENGTH_SHORT).show();
super.handleMessage(msg);
}
};
// 线程服务类
private class AcceptThread extends Thread {
private BluetoothServerSocket serverSocket;
private BluetoothSocket socket;
// 输入 输出流
private OutputStream os;
private InputStream is;
public AcceptThread() {
try {
serverSocket = mBluetoothAdapter
.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
public void run() {
// 截获客户端的蓝牙消息
try {
socket = serverSocket.accept(); // 如果阻塞了，就会一直停留在这里
is = socket.getInputStream();
os = socket.getOutputStream();
// 不断接收请求,如果客户端没有发送的话还是会阻塞
while (true) {
// 每次只发送128个字节
byte[] buffer = new byte[128];
// 读取
int count = is.read();
// 如果读取到了，我们就发送刚才的那个Toast
Message msg = new Message();
msg.obj = new String(buffer, 0, count, "utf-8");
handler.sendMessage(msg);
}
} catch (Exception e) {
// TODO: handle exception
}
}
}
}