android蓝牙操作

Posted 2022-12-06 杨迈1949

蓝牙基本操作

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 java.util.Set;

public class BluetoothActivity extends Activity 

    private static final int REQUEST_ENABLE_BT = 0x11;
    private static final int REQUEST_ENABLE_DISCOVERY = 0x12;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_bluetooth);

        // 得到蓝牙adapter
        BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        if (bluetoothAdapter == null) 
            // 设备不支持蓝牙
        


        // 打开蓝牙 - 用户是否打开蓝牙，可在onActivityResult()中判断
        if (!bluetoothAdapter.isEnabled()) 
            Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
        


        // 查找已配对过的设备
        Set<BluetoothDevice> pairedDevices = bluetoothAdapter.getBondedDevices();
        if (pairedDevices.size() > 0) 
            for (BluetoothDevice device : pairedDevices) 
                // 得到设备对象device
            
        


        // 发现周围的蓝牙设备 - 异步扫描周围的蓝牙设备，使用监听广播的方式，得到扫描到的设备
        // 请见对象deviceReceiver
        bluetoothAdapter.startDiscovery();
        // 注册广播
        IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
        registerReceiver(deviceReceiver, filter);


        // 关闭发现周围的蓝牙设备
        bluetoothAdapter.cancelDiscovery();


        // 当前蓝牙设备能被发现，在300秒内，可在onActivityResult()中判断用户是否同意,该方法会自动打开蓝牙
        Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
        discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
        startActivityForResult(discoverableIntent, REQUEST_ENABLE_DISCOVERY);

        // 得到蓝牙mac地址
        bluetoothAdapter.getAddress();

        // 通过蓝牙mac地址，得到蓝牙设备
        BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);

    

    private final BroadcastReceiver deviceReceiver = new BroadcastReceiver() 
        public void onReceive(Context context, Intent intent) 
            String action = intent.getAction();
            if (BluetoothDevice.ACTION_FOUND.equals(action)) 
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                // 拿到发现得蓝牙设备对象device,注意同一台设备可能会有多次返回
            
        
    ;


    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) 
        if (resultCode == RESULT_CANCELED) 
            if (requestCode == REQUEST_ENABLE_BT) 
                // 用户没有打开蓝牙
             else if (requestCode == REQUEST_ENABLE_DISCOVERY) 
                // 用户不想让设备被扫描到
            
         else 
            if ((requestCode == REQUEST_ENABLE_BT)) 
                // 用户打开了蓝牙
             else if (requestCode == REQUEST_ENABLE_DISCOVERY) 
                // 用户同意设备被扫描到
            
        
    

    @Override
    protected void onDestroy() 
        // 注销广播
        unregisterReceiver(deviceReceiver);
        super.onDestroy();
    

蓝牙传输文件

使用默认的系统蓝牙应用，发送文件给另一台支持蓝牙设备

在Android系统中，使用蓝牙可以分享文件给另一台蓝牙设备，这样一种传输方式，使用的就是OBEX协议。按我的理解，所有蓝牙设备都支持OBEX协议。
在文件管理器中，可以分享文件，但是会弹出很多的分享目标：QQ,微信,蓝牙等…，若想实现这个功能，就需要直接调用蓝牙分享，下面代码使用的就是这个思路，摘录自：http://www.2cto.com/kf/201401/270305.html；

    private void sendFile(Activity activity, File file) 
        PackageManager localPackageManager = activity.getPackageManager();
        Intent localIntent = null;

        HashMap<String, ActivityInfo> localHashMap = null;

        try 
            localIntent = new Intent();
            localIntent.setAction(Intent.ACTION_SEND); // 设置为分享ACTION
            localIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(file)); // 添加传输文件
            // localIntent.putExtra(Intent.EXTRA_STREAM,
            // Uri.fromFile(new File(localApplicationInfo.sourceDir)));
            localIntent.setType("*/*"); // 设置应用的打开方式
            List<ResolveInfo> localList = localPackageManager.queryIntentActivities(
                    localIntent, 0); // 查找所有可以处理该intent的
            localHashMap = new HashMap<String, ActivityInfo>();
            Iterator<ResolveInfo> localIterator1 = localList.iterator();
            while (localIterator1.hasNext()) 
                ResolveInfo resolveInfo = (ResolveInfo) localIterator1.next();
                ActivityInfo localActivityInfo2 = resolveInfo.activityInfo;
                String str = localActivityInfo2.applicationInfo.processName;
                if (str.contains("bluetooth"))
                    localHashMap.put(str, localActivityInfo2); // 添加所有包含bluetooth关键字的程序
            
         catch (Exception e) 
            Toast.makeText(BluetoothShareActivity.this, "蓝牙分享异常：" + e.getMessage(), Toast.LENGTH_SHORT).show();
        
        if (localHashMap.size() == 0)
            Toast.makeText(BluetoothShareActivity.this, "无蓝牙设备分享", Toast.LENGTH_SHORT).show();
        ActivityInfo localActivityInfo1 = (ActivityInfo) localHashMap
                .get("com.android.bluetooth");
        if (localActivityInfo1 == null) 
            localActivityInfo1 = (ActivityInfo) localHashMap
                    .get("com.mediatek.bluetooth");
        
        if (localActivityInfo1 == null) 
            Iterator<ActivityInfo> localIterator2 = localHashMap.values().iterator();
            if (localIterator2.hasNext())
                localActivityInfo1 = (ActivityInfo) localIterator2.next();
        
        if (localActivityInfo1 != null) 
            localIntent.setComponent(new ComponentName(
                    localActivityInfo1.packageName, localActivityInfo1.name));
            activity.startActivityForResult(localIntent, 4098); // 请求处理intent
            return;