蓝牙(2)用BluetoothAdapter搜索蓝牙设备示例

注意在搜索之前要先打开蓝牙设备

package com.e.search.bluetooth.device;

import java.util.Set;

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.Window;
import android.widget.TextView;

public class Main extends Activity {
    //搜索蓝牙设备第1步,在manifest.xml中加入权限
    /*
     *  <uses-permission android:name="android.permission.BLUETOOTH" />
     *    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
     */
    
    //搜索蓝牙设备第2步,准备BluetoothAdapter
    private BluetoothAdapter mBluetoothAdapter;
    private TextView tvDevices;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
        setContentView(R.layout.main);

        tvDevices = (TextView) findViewById(R.id.tvDevices);
        //搜索蓝牙设备第3步,获取或创建BluetoothAdapter
        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

        //搜索蓝牙设备第4步,得到已经配对的蓝牙设备.
        Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();

        if (pairedDevices.size() > 0) {
            //枚举已经配对的设备的名字和地址.
            for (BluetoothDevice device : pairedDevices) {
                tvDevices.append(device.getName() + ":" + device.getAddress());
            }
        }

        //搜索蓝牙设备第5步,用广播接收器得到蓝牙找到设备和搜索完成广播消息.
        //注册找到蓝牙设备广播接收器,用filter注册
        IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
        this.registerReceiver(receiver, filter);
        
        //注册搜索蓝牙设备已完成广播接收器,用filter注册
        filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
        this.registerReceiver(receiver, filter);

    }

    /*
     * 开始搜索按钮
     */
    public void onClick_Search(View view) {
        //显示进度条
        setProgressBarIndeterminateVisibility(true);
        setTitle("正在搜索...");
        //搜索蓝牙设备第6步,开始搜索蓝牙设备.
        if (mBluetoothAdapter.isDiscovering()) {//如果正在搜索,那么先取消.
            mBluetoothAdapter.cancelDiscovery();
        }
        mBluetoothAdapter.startDiscovery();//异步的开始搜索.
    }
    //搜索蓝牙设备第7步,处理找到蓝牙设备和搜索完成广播消息.
    private final BroadcastReceiver receiver = new BroadcastReceiver() {

        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if (BluetoothDevice.ACTION_FOUND.equals(action)) {//找到蓝牙设备
                
                //搜索蓝牙设备第8步,搜到蓝牙设备.
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
                //搜索蓝牙设备第9步,把设备添加到已找到列表中,这里只是显示它的信息.
                    tvDevices.append(device.getName() + ":"+ device.getAddress() + "\n");
                }
            } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.//搜索完成
                    equals(action)) {
                //搜索蓝牙设备第10步,搜索完毕.
                setProgressBarVisibility(false);
                setTitle("已搜素完成");
            }
        }
    };
}