private async void Button_Tapped(object sender, TappedRoutedEventArgs e)
{
byte[] message = Encoding.UTF8.GetBytes(message_textbox.Text);
if (publicKey != null)
{
byte[] dataToSend = PGP.Encrypt(message, publicKey, true, true);
await MailHelper.ComposeEmailAsync(contact, "Encoded message", string.Empty, "message.pgp", dataToSend);
}
}
