Question

我正在开发一个Android应用程序，其中包括向用户显示附近蓝牙设备的列表并连接到他们选择的设备。我试图使用系统蓝牙设备选择器，如以下帖子所示：

How to retrieve Bluetooth device info with Android Bluetooth device picker?

设备选择器确实显示，但我无法找到我的代码中选择了哪个设备。 onReceive内的吐司没有显示，这表明没有接收到广播。

我遇到的另一个问题是，如果我尝试在onRequestPermissionsResult内启动设备选择器活动，则设备选择器根本不显示，尽管点击“允许”＃39;在请求权限对话框中。里面的吐司也没有显示出来。

以下是代码：

//Code inside Fragment
BroadcastReceiver mReceiver;
BluetoothAdapter bluetoothAdapter;
BluetoothSocket bsock;


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    myView = inflater.inflate(R.layout.controller_mode_layout,container,false);

     bluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); 
//Get location access permission.
    if (bluetoothAdapter != null) {
        if (bluetoothAdapter.isEnabled()) {
            ActivityCompat.requestPermissions(getActivity(),new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, reqCode);
        }
    }
//Receiver to get the selected device information 
    mReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
                context.unregisterReceiver(this);
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
            Toast.makeText(context,"Device"+device.getAddress(), Toast.LENGTH_SHORT).show();
            try {
                bsock=device.createRfcommSocketToServiceRecord(UUID.fromString("00002415-0000-1000-8000-00805F9B34FB"));
                bsock.connect();
                //Send and receive data logic follows

            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    };
    getActivity().registerReceiver(mReceiver, new IntentFilter("android.bluetooth.devicepicker.action.DEVICE_SELECTED"));

    showDevicePicker();

    return myView;
}



@Override
public void onRequestPermissionsResult (int requestCode, String[] permissions, int[] grantResults)
{
    Toast.makeText(getActivity(),"Permission result", Toast.LENGTH_SHORT).show();
    if((requestCode == reqCode) && (grantResults[0] == PackageManager.PERMISSION_GRANTED))
    {
        //Not working
       // showDevicePicker();
    }
}

public void showDevicePicker()
{
    //Launch built in bluetooth device picker activity
    startActivity( new Intent("android.bluetooth.devicepicker.action.LAUNCH")
            .putExtra("android.bluetooth.devicepicker.extra.NEED_AUTH", false)
            .putExtra("android.bluetooth.devicepicker.extra.FILTER_TYPE", 0)
            .putExtra("android.bluetooth.devicepicker.extra.LAUNCH_PACKAGE","com.example.ankit2.controllerapp1")
            .putExtra("android.bluetooth.devicepicker.extra.DEVICE_PICKER_LAUNCH_CLASS","com.example.ankit2.controllerapp1.Fragment1")
            .setFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS));

}

任何帮助将不胜感激。

注意：我在运行Marshmallow的Lenovo K3笔记上测试了代码。

Answer 1

问题出在var arrayOfData : [String] = [] dispatch_async(dispatch_get_main_queue(),{ for data in json as! [Dictionary<String,AnyObject>] { let data1 = data["People"] arrayOfData.append(data1!) } })，其中指定为DEVICE_PICKER_LAUNCH_CLASS。即使广播接收器位于片段内，启动类也必须是活动。在这种情况下，将启动类更改为Fragment1（包含片段ControllerActivity）可以解决问题。

从Android蓝牙设备选择器

1 个答案: