async void Current_OnMessageReceived(ITagInfo tagInfo)
{
if (tagInfo == null)
{
await ShowAlert("No tag found");
return;
}
// Customized serial number
var identifier = tagInfo.Identifier;
var serialNumber = NFCUtils.ByteArrayToHexString(identifier, ":");
var title = !string.IsNullOrWhiteSpace(serialNumber) ? $"Tag [{serialNumber}]" : "Tag Info";
if (!tagInfo.IsSupported)
{
await ShowAlert("Unsupported tag (app)", title);
}
else if (tagInfo.IsEmpty)
{
await ShowAlert("Empty tag", title);
}
else
{
var first = tagInfo.Records[0];
await ShowAlert(GetMessage(first), title);
}
}
private void CurrentOnOnMessageReceived(ITagInfo tagInfo)
{
AppendText("MessageReceived");
AppendText($"SerialNumber = {tagInfo.SerialNumber}");
var id = NFCUtils.ByteArrayToHexString(tagInfo.Identifier);
AppendText($"Identifier = {id}");
AppendText($"tagInfo.IsEmpty = {tagInfo.IsEmpty}");
AppendText($"tagInfo.IsWritable = {tagInfo.IsWritable}");
if (tagInfo.Records != null && tagInfo.Records.Any())
{
AppendText($"tagInfo.Records.Length = {tagInfo.Records.Length}");
foreach (var record in tagInfo.Records)
{
if (record.Payload != null && record.Payload.Any())
{
var payload = NFCUtils.ByteArrayToHexString(record.Payload);
AppendText($"record.Payload = {payload}");
}
if (record.Message != null)
{
AppendText($"record.Message = {record.Message}");
}
}
}
Device.BeginInvokeOnMainThread(CrossNFC.Current.StartListening);
Analytics.TrackEvent("NfcTag", new Dictionary <string, string> {
{ "Identifier", id }
});
}
/// <summary>
/// Custom contructor
/// </summary>
/// <param name="identifier">Tag Identifier as <see cref="byte[]"/></param>
/// <param name="isNdef">Is Ndef tag</param>
public TagInfo(byte[] identifier, bool isNdef = true)
{
Identifier = identifier;
SerialNumber = NFCUtils.ByteArrayToHexString(identifier);
IsSupported = isNdef;
}
protected override void OnNewIntent(Intent intent)
{
//base.OnNewIntent(intent);
// CrossNFC.OnNewIntent(intent);
string manuf = "";
string data = "";
string serialNumber = "";
TagRead tagRead = new TagRead();
if (intent.Action == NfcAdapter.ActionTagDiscovered)
{
List <string> tags = new List <string>();
NdefMessage ndefMessage = null;
var id = intent.GetByteArrayExtra(NfcAdapter.ExtraId);
if (id != null)
{
serialNumber = NFCUtils.ByteArrayToHexString(id, ":");
/*for (int ii = 0; ii < id.Length; ii++)
* {
* if (!string.IsNullOrEmpty(data))
* serialNumber += "-";
* serialNumber += id[ii].ToString("X2");
* }*/
tagRead.SerialNumber = serialNumber;
tags.Add(serialNumber);
}
else
{
tags.Add(null);
}
var tag = intent.GetParcelableExtra(NfcAdapter.ExtraTag) as Tag;
if (tag != null)
{
manuf = NFCHelpers.GetManufacturer(tag);
tags.Add(manuf);
tagRead.Model = manuf;
if (NFCHelpers.IsNDEFTag(tag))
{
var ndef = Ndef.Get(tag);
if (ndef != null)
{
if (ndefMessage == null)
{
ndefMessage = ndef.CachedNdefMessage;
}
if (ndefMessage != null)
{
NdefRecord[] records = ndefMessage.GetRecords();
var ndefrecords = NFCHelpers.GetRecords(records);
for (var i = 0; i < ndefrecords.Count; i++)
{
if (data != "")
{
data += "\n";
}
data += ndefrecords[i];
}
tags.Add(data);
tagRead.Data = data;
}
}
}
/*
* var rawTagMessages = intent.GetParcelableArrayExtra(NfcAdapter.ExtraTag);
*
* // First get all the NdefMessage
* var rawMessages = intent.GetParcelableArrayExtra(NfcAdapter.ExtraNdefMessages);
* if (rawMessages != null)
* {
*
* // https://medium.com/@ssaurel/create-a-nfc-reader-application-for-android-74cf24f38a6f
*
* foreach (var message in rawMessages)
* {
*
* foreach (var r in NdefMessageParser.GetInstance().Parse((NdefMessage)message))
* {
* System.Diagnostics.Debug.WriteLine("TAG: " + r.Str());
* tags.Add(r.Str());
* }
*
* }
* }*/
}
MessagingCenter.Send <App, TagRead>((App)Xamarin.Forms.Application.Current, "Tag", tagRead);
}
else if (intent.Action == NfcAdapter.ActionNdefDiscovered)
{
System.Diagnostics.Debug.WriteLine("ActionNdefDiscovered");
}
}