public Task <LocalAuthResult> AuthenticateAsync(string reason)
{
// CryptoObjectHelper is described in the previous section.
var cryptoHelper = new CryptoObjectHelper();
var context = Android.App.Application.Context;
if (Android.OS.Build.VERSION.SdkInt >= Android.OS.BuildVersionCodes.M)
{
/* ==================================================================================================
* android api 23 or higher
* ================================================================================================*/
var manager = context.GetSystemService(Context.FingerprintService) as FingerprintManager;
// cancellationSignal can be used to manually stop the fingerprint scanner.
var cancellationSignal = new Android.OS.CancellationSignal();
var authenticationCallback = new SimpleAuthCallback();
// Start the fingerprint scanner.
manager.Authenticate(cryptoHelper.BuildCryptoObject(), cancellationSignal, FingerprintAuthenticationFlags.None, authenticationCallback, null);
}
// Using the Android Support Library v4
var managerCompat = FingerprintManagerCompat.From(context);
// cancellationSignal can be used to manually stop the fingerprint scanner.
var cancellationSignalCompat = new Android.Support.V4.OS.CancellationSignal();
// AuthenticationCallback is a base class that will be covered later on in this guide.
var callbackCompat = new SimpleCompatAuthCallback();
// Start the fingerprint scanner.
managerCompat.Authenticate(cryptoHelper.BuildCompatCryptoObject(), 0, cancellationSignalCompat, callbackCompat, null);
//return new LocalAuthResult(false);
return(Task.FromResult(new LocalAuthResult(false)));
}
public override void OnWrite(PageRange[] pages, Android.OS.ParcelFileDescriptor destination, Android.OS.CancellationSignal cancellationSignal, WriteResultCallback callback)
{
try
{
using (InputStream input = new FileInputStream(_filePath))
{
using (OutputStream output = new FileOutputStream(destination.FileDescriptor))
{
var buf = new byte[1024];
int bytesRead;
while ((bytesRead = input.Read(buf)) > 0)
{
output.Write(buf, 0, bytesRead);
}
}
}
callback.OnWriteFinished(new[] { PageRange.AllPages });
}
catch (FileNotFoundException fileNotFoundException)
{
System.Diagnostics.Debug.WriteLine(fileNotFoundException);
}
catch (Exception exception)
{
System.Diagnostics.Debug.WriteLine(exception);
}
}
public override void OnLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, Android.OS.CancellationSignal cancellationSignal, LayoutResultCallback callback, Android.OS.Bundle extras)
{
if (cancellationSignal.IsCanceled)
{
callback.OnLayoutCancelled();
return;
}
callback.OnLayoutFinished(new PrintDocumentInfo.Builder(_fileName)
.SetContentType(PrintContentType.Document)
.Build(), true);
}
public override void OnWrite(PageRange[] pages, Android.OS.ParcelFileDescriptor destination, Android.OS.CancellationSignal cancellationSignal, WriteResultCallback callback)
{
InputStream input = null;
OutputStream output = null;
try {
input = new FileInputStream(_filePath);
output = new FileOutputStream(destination.FileDescriptor);
byte[] buf = new byte[1024];
int bytesRead;
while ((bytesRead = input.Read(buf)) > 0)
{
output.Write(buf, 0, bytesRead);
}
callback.OnWriteFinished(new PageRange[] { PageRange.AllPages });
} catch (FileNotFoundException ee) {
//Catch exception
} catch (Exception e) {
//Catch exception
} finally {
try {
input.Close();
output.Close();
} catch (IOException e) {
e.PrintStackTrace();
}
}
}
