一. 什么是蓝牙(Bluetooth)?
1.1 BuleTooth是目前使用最广泛的无线通信协议
1.2 主要针对短距离设备通讯(10m)
1.3 常用于连接耳机，鼠标和移动通讯设备等.
二. 与蓝牙相关的API
2.1 BluetoothAdapter:
代表了本地的蓝牙适配器
2.2 BluetoothDevice
代表了一个远程的Bluetooth设备
三. 扫描已经配对的蓝牙设备(1)
注：必须部署在真实手机上，模拟器无法实现
首先需要在AndroidManifest.xml 声明蓝牙权限
<user-permission android:name="android.permission.BLUETOOTH" />
配对蓝牙需要手动操作:
1. 打开设置--> 无线网络 --> 蓝牙 勾选开启
2. 打开蓝牙设置 扫描周围已经开启的蓝牙设备(可以与自己的笔记本电脑进行配对)，点击进行配对
电脑上会弹出提示窗口: 添加设备
显示计算与设备之间的配对码，要求确认是否配对
手机上也会显示类似的提示.
四. 扫描已经配对的蓝牙设备(2)
4.1 获得BluetoothAdapter对象
4.2 判断当前移动设备中是否拥有蓝牙
4.3 判断当前移动设备中蓝牙是否已经打开
4.4 得到所有已经配对的蓝牙设备对象
蓝牙配对实现的核心代码如下:
MainActivity:
import java.util.Iterator;
import java.util.Set;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
private Button button = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button = (Button)findViewById(R.id.buttonId);
button.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View v) {
//获得BluetoothAdapter对象，该API是android 2.0开始支持的
BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter();
//adapter不等于null，说明本机有蓝牙设备
if(adapter != null){
System.out.println("本机有蓝牙设备！");
//如果蓝牙设备未开启
if(!adapter.isEnabled()){
Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
//请求开启蓝牙设备
startActivity(intent);
}
//获得已配对的远程蓝牙设备的集合
Set<BluetoothDevice> devices = adapter.getBondedDevices();
if(devices.size()>0){
for(Iterator<BluetoothDevice> it = devices.iterator();it.hasNext();){
BluetoothDevice device = (BluetoothDevice)it.next();
//打印出远程蓝牙设备的物理地址
System.out.println(device.getAddress());
}
}else{
System.out.println("还没有已配对的远程蓝牙设备！");
}
}else{
System.out.println("本机没有蓝牙设备！");
}
}
});
}
}
修改本机蓝牙设备的可见性,并扫描周围可用的蓝牙设备
1. 修改本机蓝牙设备的可见性
2. 扫描周围可用的蓝牙设备
Eg:
一. 清单文件AdroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.se7en"
android:versionCode="1"
android:versionName="1.0">
<uses-sdk android:minSdkVersion="8" />
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".MainActivity"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
<uses-permission android:name="android.permission.BLUETOOTH"/>
<!-若需要管理蓝牙设备，如修改可见性，则需以下的权限->
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
</manifest>
二. 布局文件: main.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<Button
android:id="@+id/discoverButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="设置可见性"/>
<Button
android:id="@+id/scanButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="开始扫描"/>
</LinearLayout>
三. MainActivity:
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
private Button discoverButton = null;
private Button scanButton = null;
private BluetoothAdapter adapter = null;
private BluetoothReceiver bluetoothReceiver = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
adapter = BluetoothAdapter.getDefaultAdapter();
discoverButton = (Button)findViewById(R.id.discoverButton);
scanButton = (Button)findViewById(R.id.scanButton);
//修改蓝牙设备的可见性
discoverButton.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View view) {
Intent discoverIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
//设置蓝牙可见性，500表示可见时间（单位：秒），当值大于300时默认为300
discoverIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION,500);
startActivity(discoverIntent);
}
});
scanButton.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View v) {
//开始扫描周围蓝牙设备，该方法是异步调用并以广播的机制返回，所以需要创建一个BroadcastReceiver来获取信息
adapter.startDiscovery();
}
});
//设定广播接收的filter
IntentFilter intentFilter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
//创建蓝牙广播信息的receiver
bluetoothReceiver = new BluetoothReceiver ();
//注册广播接收器
registerReceiver(bluetoothReceiver,intentFilter);
}
private class BluetoothReceiver extends BroadcastReceiver{
@Override
public void onReceive(Context context, Intent intent) {
//获得扫描到的远程蓝牙设备
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
System.out.println(device.getAddress());
}
}
}
