Xamarin Wifi 和蓝牙伴侣配对

Question

Edit: Moved originally Answer out of the Questions section and into the Answers section so this can be more easily understood.

I had some issues trying to implement android companion device pairing. I am still having issues with WiFi pairing/bonding. I could not find any real information on this (I assume it is not just a P2P connection). Source documents are shown below.

Link to Java Pairing: Android companion device pairing

Link to Microsoft Documentation: Microsoft's documentation

The Answer I came up is below but is still missing the WiFi component for bonding.

Answer 1

I could not really find documentation on how to use the C# Android companion device pairing. I wanted to share how you can implement part of it and not face some of the frustration I have faced trying to track down and piece together how the system should work. Please if you see better ways to accomplish any of these tasks or if you know how to complete the WiFi bond please post the answer.

1)First set up your Manifest (permissions are set in properties of the android project if using visual studio and the uses-feature I think needs to be typed in). I probably have more on this list than needed.

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.REQUEST_COMPANION_USE_DATA_IN_BACKGROUND" />
<uses-permission android:name="android.permission.REQUEST_COMPANION_RUN_IN_BACKGROUND" />
<uses-permission android:name="android.permission.CALL_COMPANION_APP" />
<uses-permission android:name="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE" />
<uses-permission android:name="android.permission.ACCESS_NOTIFICATION_POLICY" />
<uses-permission android:name="android.permission.SET_ACTIVITY_WATCHER" />
<uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
<uses-permission android:name="android.permission.LOCATION_HARDWARE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH_PRIVILEGED" />
<uses-feature android:name="android.software.companion_device_setup" />

2. Set up your request. In this example I included all 3 setup types. I have not really figure out the filters but this should at least set you on the right direction. I made the methods more complex than they needed to be but this made is easier for me to read. The interior portions can be removed and all put in a single method. IAssociationRequest is a custom Interface for requesting MakeRequest method.

Note: I have no idea if these are the right Activity tags. I really could not find anything on the ones to use but these do work.

{
    public class CompanionAssociationRequest : CompanionDeviceManager.Callback, IAssociationRequest
    {
        #region variables
        public static int SELECT_DEVICE_REQUEST_CODE = 0;
        AssociationRequest _request { get; set; }
        AssociationRequest.Builder _requestBuilder { get; set; }
        #region Bluetooth
        BluetoothDeviceFilter _filter { get; set; }
        BluetoothDeviceFilter.Builder _filterBuilder { get; set; }
        #endregion
        #region Wifi
        //WifiDeviceFilter _filter { get; set; }
        //WifiDeviceFilter.Builder _filterBuilder { get; set; }
        #endregion
        CompanionDeviceManager _companionDeviceManager { get; set; }
        CompanionDeviceManager.Callback _callback { get; set; }                
        Context _context = Android.App.Application.Context;        
        #endregion

        #region Assocaiation Request
        public async Task MakeRequest()
        {
            try
            {
                await HasNotificationAccess();
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }

            try
            {
                _companionDeviceManager = (CompanionDeviceManager)Forms.Context.GetSystemService(Context.CompanionDeviceService);                
                await Request();                
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }

            try
            {
                Console.WriteLine(_request.ToString());                
                _companionDeviceManager.Associate(_request, CompanionDeviceManagerCallback().Result, null);
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }
        }

        #endregion

        #region Filter and Request building
        private async Task Request()
        {
            try
            {
                await RequestBuilder();
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }

            try
            {
                _request = _requestBuilder.Build();
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }
        }
        private async Task RequestBuilder()
        {
            try
            {
                await Filter();
                _requestBuilder = new AssociationRequest.Builder();
                _requestBuilder.AddDeviceFilter(_filter);
                _requestBuilder.SetSingleDevice(false);

            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }            
        }
        private async Task FilterBuilder()
        {
            try
            {
                #region Bluetooth
                _filterBuilder = new BluetoothDeviceFilter.Builder();
                #endregion
                #region Wifi
                //_filterBuilder = new WifiDeviceFilter.Builder();                
                //_filterBuilder.SetNamePattern(Java.Util.Regex.Pattern.Compile(""));//I dont know if this works
                //_filterBuilder.SetBssid();                
                #endregion
                _filter = _filterBuilder.Build();
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }            
        }
        private async Task Filter()
        {
            try
            {                
                await FilterBuilder();
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }            
        }
        #endregion

        #region callback and overrides

        private async Task<CompanionDeviceManager.Callback> CompanionDeviceManagerCallback()
        {

            try
            {                
                _callback = DependencyService.Get<CompanionDeviceManager.Callback>();             
            }
            catch (Exception ex) { Console.WriteLine(ex.StackTrace); }
            return _callback;
        }

        public override void OnDeviceFound(IntentSender chooserLauncher)
        {
            try
            {               
                DeviceSelectionRequest(chooserLauncher);
            }
            catch (Exception ex)
            {                
                Console.WriteLine(ex.StackTrace);
            }
        }

        public override void OnFailure(Java.Lang.ICharSequence error)
        {
            try
            {
                //add notification here
                Console.WriteLine("Devices not found");                      
            }
            catch (Exception ex)
            {                
                Console.WriteLine(ex.StackTrace);
            }
        }

        private void DeviceSelectionRequest(IntentSender chooserLauncher)
        {            
            try
            {
                #region activity result                
                ActivityFlags flagsMask = ActivityFlags.BroughtToFront;
                ActivityFlags flagsValues = ActivityFlags.NewTask;
                int extraFlags = 0;
                Intent fillInIntent = null;
                ((Activity)Forms.Context).StartIntentSenderForResult(chooserLauncher, SELECT_DEVICE_REQUEST_CODE, fillInIntent, flagsMask, flagsValues, extraFlags);
                #endregion   
            }
            catch (Exception ex)
            {                
                Console.WriteLine(ex.StackTrace);
            }
        }

        #endregion
                
        #region notification access
        public async Task HasNotificationAccess()
        {
            bool hasAccess = NotificationManagerCompat.From(_context).AreNotificationsEnabled();
            if (!hasAccess)
            {
                await AskForNotificationAccess();
            }
        }

        public async Task AskForNotificationAccess()
        {

            Console.WriteLine("notificaitons do not have access");
        }

        #endregion
    }
}

3. Make sure you have an assembly reference over your namespace

[assembly: Xamarin.Forms.Dependency(typeof(Foo.Bar.Droid.SomeFileName.CompanionAssociationRequest))]

4. Now put the OnActivityResult in the MainActivity. It will not seem to work anywhere else. I could not figure out how to use the WiFi pairing so if you have an idea please let me know.

Note: I don't know JAVA so hopefully this is a good approximation of what it is suppose to be.

    protected override void OnActivityResult(int requestCode, Result resultCode, Intent data)
        {
            base.OnActivityResult(requestCode, resultCode, data);
            try
            {
                if (resultCode != Result.Ok)
                {
                    return;
                }
                if (requestCode == CompanionAssociationRequest.SELECT_DEVICE_REQUEST_CODE && data != null)
                {
                    #region Bluetooth                    
                    BluetoothDevice deviceToPair = (BluetoothDevice)data.GetParcelableExtra(CompanionDeviceManager.ExtraDevice);
                    #endregion
                    #region BluetoothLE                    
                    //Android.Bluetooth.LE.ScanResult deviceToPair = (Android.Bluetooth.LE.ScanResult)data.GetParcelableExtra(CompanionDeviceManager.ExtraDevice);
                    #endregion
                    #region Wifi                    
                    //Android.Net.Wifi.ScanResult deviceToPair = (Android.Net.Wifi.ScanResult)data.GetParcelableExtra(CompanionDeviceManager.ExtraDevice);
                    #endregion
                    if (deviceToPair != null)
                    {
                        #region Bluetooth
                        deviceToPair.CreateBond();
                        #endregion
                        #region BluetoothLE                        
                        //deviceToPair.Device.CreateBond();                        
                        #endregion
                        #region Wifi
                        //???
                        //Have been trying a few things but could not figure it out. 
                        #endregion
                        //do more stuff
                    }
                }
                else
                {
                    base.OnActivityResult(requestCode, resultCode, data);
                }
            }
            catch (Exception ex)
            {                
                Console.WriteLine(ex.Message);
            }
        }}

I have not really tried the BluetoothLE but I think it should work. Hopefully this helps someone banging their head on their desk and if anyone has any improvements I would appreciate input.

Link to Java Pairing: Android companion device pairing

Link to Microsoft Documentation: Microsoft's documentation

These are really some of the only docs I could find and stumbled around to find some of the other ways to get the system to run. This is almost an exact translation from the Java Pairing example but it still took me quite a while to figure out how to format and figure out how it is suppose to work together. I have not been working on the filters yet, hopefully they will be easier to setup.