Estaba tratando de enviar un correo electrónico sin la interacción del usuario. Todo funcionó hasta la parte por enviar.

Esta es la función sendemail en la clase Gmailsender que estoy usando

public void sendEmail() throws MessagingException 
{
    Log.i("check","start");

String host = "smtp.gmail.com";
String from = "[email protected]"; //sender email, this is our website email
String pass = "blablabla"; //password of sender email

Properties props = System.getProperties();
props.put("mail.smtp.starttls.enable", "true"); // added this line
props.put("mail.smtp.host", host);
props.put("mail.smtp.user", from);
props.put("mail.smtp.password", pass);
props.put("mail.smtp.port", "587");
props.put("mail.smtp.auth", "true");
Log.i("check","done pops ");


//creating session
Session session = Session.getDefaultInstance(props, null);
MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));
Log.i("check","done sessions ");

InternetAddress toAddress;     
    toAddress = new InternetAddress(to);    
    message.addRecipient(Message.RecipientType.TO, toAddress);
    Log.i("check","add recipante ");

message.setSubject(subject);
message.setText("This is my app");


Log.i("check","transport");

Transport transport = session.getTransport("smtp");

//connecting..
Log.i("check","connecting");
transport.connect(host, from, pass);
//sending...
Log.i("check","wana send");
transport.sendMessage(message, message.getAllRecipients());
transport.close();
Log.i("check","sent");

}

El registro "quiero enviar" no aparece ...

La actividad principal que estoy creando un objeto de gmailSender tiene el siguiente código:

 send = (Button) this.findViewById(R.id.button1);
    send.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            // TODO Auto-generated method stub
            try {   
                GMailSender sender = new GMailSender("[email protected]", "blablabla");
                Log.e("check", "test 1");
                sender.sendEmail() ;
                Log.e(DEBUG_TAG, "test 2");  
            } catch (Exception e) {   
                Log.e(DEBUG_TAG, "test 3");                  } 

Estoy obteniendo el registro de "prueba 3" lo que significa que ocurrió la excepción ...

El resultado es que el correo electrónico no se envía y la aplicación está bloqueada ... No sé cuál es el problema.

NOTA: Agregué el permiso de internet + Agregué los archivos jar

El logcat es

12-25 12:55:00.774: E/check(1350): test 1
12-25 12:55:00.774: I/check(1350): start
12-25 12:55:00.774: I/check(1350): done pops 
12-25 12:55:00.774: I/check(1350): done sessions 
12-25 12:55:00.774: I/check(1350): add recipante 
12-25 12:55:00.779: I/check(1350): transport
12-25 12:55:00.789: I/check(1350): connecting
12-25 12:55:00.789: E/check(1350): test 3

este es el logcat completo para la etiqueta de verificación:

12-25 13:20:18.698: E/check(5547): test 1
12-25 13:20:18.698: I/check(5547): start
12-25 13:20:18.698: I/check(5547): done pops 
12-25 13:20:18.723: I/check(5547): done sessions 
12-25 13:20:18.723: I/check(5547): add recipante 
12-25 13:20:18.723: I/check(5547): transport
12-25 13:20:18.733: I/check(5547): connecting
12-25 13:20:18.758: E/check(5547): [Ljava.lang.StackTraceElement;@4193bb00
12-25 13:20:18.758: E/check(5547): android.os.NetworkOnMainThreadException
12-25 13:20:18.758: E/check(5547):  at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
12-25 13:20:18.758: E/check(5547):  at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
12-25 13:20:18.758: E/check(5547):  at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
12-25 13:20:18.758: E/check(5547):  at java.net.InetAddress.getByName(InetAddress.java:295)
12-25 13:20:18.758: E/check(5547):  at java.net.InetSocketAddress.<init>(InetSocketAddress.java:105)
12-25 13:20:18.758: E/check(5547):  at java.net.InetSocketAddress.<init>(InetSocketAddress.java:90)
12-25 13:20:18.758: E/check(5547):  at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:233)
12-25 13:20:18.758: E/check(5547):  at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:189)
12-25 13:20:18.758: E/check(5547):  at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1359)
12-25 13:20:18.758: E/check(5547):  at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:412)
12-25 13:20:18.758: E/check(5547):  at javax.mail.Service.connect(Service.java:288)
12-25 13:20:18.758: E/check(5547):  at javax.mail.Service.connect(Service.java:169)
12-25 13:20:18.758: E/check(5547):  at com.example.sendmail.GMailSender.sendEmail(GMailSender.java:100)
12-25 13:20:18.758: E/check(5547):  at com.example.sendmail.MailSenderActivity$1.onClick(MailSenderActivity.java:31)
12-25 13:20:18.758: E/check(5547):  at android.view.View.performClick(View.java:3627)
12-25 13:20:18.758: E/check(5547):  at android.view.View$PerformClick.run(View.java:14329)
12-25 13:20:18.758: E/check(5547):  at android.os.Handler.handleCallback(Handler.java:605)
12-25 13:20:18.758: E/check(5547):  at android.os.Handler.dispatchMessage(Handler.java:92)
12-25 13:20:18.758: E/check(5547):  at android.os.Looper.loop(Looper.java:137)
12-25 13:20:18.758: E/check(5547):  at android.app.ActivityThread.main(ActivityThread.java:4511)
12-25 13:20:18.758: E/check(5547):  at java.lang.reflect.Method.invokeNative(Native Method)
12-25 13:20:18.758: E/check(5547):  at java.lang.reflect.Method.invoke(Method.java:511)
12-25 13:20:18.758: E/check(5547):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:980)
12-25 13:20:18.758: E/check(5547):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:747)
12-25 13:20:18.758: E/check(5547):  at dalvik.system.NativeStart.main(Native Method)