android之蓝牙操作（一）
与蓝牙相关的API

1、BluetoothAdapter
该类的对象代表了本地的蓝牙适配器
2、BluetoothDevice
该类的对象代表了远程的蓝牙适配器

扫描已经配对的蓝牙设备步骤：

1、获得BluetoothAdapter对象
2、判断当前的设备中是否有蓝牙设备
3、判断当前设备中的蓝牙设备是否已经打开
4、得到所以已经配对的蓝牙设备对象

在AndroidManifedt.xml中声明蓝牙权限

在布局文件中添加一个按钮
main.xml




MainActivity.java

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 TestBluetoothActivity extends Activity {    /** Called when the activity is first created. */private Button button = null;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);                button = (Button)findViewById(R.id.button);        button.setOnClickListener(new ButtonListener());    }    private class ButtonListener implements OnClickListener    {@Overridepublic void onClick(View v) {// TODO Auto-generated method stub//得到BluetoothAdapter对象BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();//判断BluetoothAdapter对象是否为空，若为空，则本机上无蓝牙设备if (bluetoothAdapter != null) {System.out.println("本机上拥有蓝牙设备");if (!bluetoothAdapter.enable()) {//创建一个Intent对象，该对象用来启动另外一个Activity，提示用户启动蓝牙设备Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);startActivity(intent);}//得到所有已经匹配的蓝牙适配器对象Set<BluetoothDevice> device = bluetoothAdapter.getBondedDevices();if (device.size()>0) {for (Iterator iterator = device.iterator(); iterator.hasNext();) {BluetoothDevice bluetoothDevice = (BluetoothDevice) iterator.next();System.out.println(bluetoothDevice.getAddress());}}}else {System.out.println("本机上无蓝牙设备");}}        }}