can'；不要使用android代码发送邮件

我正在尝试在应用程序中发送邮件。我不会弹出任何与用户的交互。我有两个java代码

MainActivity.java

package com.example.test;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends Activity {
public static String EXTRA_MESSAGE = "com.example.MESSAGE";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main, menu);
    return super.onCreateOptionsMenu(menu);

}

public void sendMessage(View view)
{
    try {   
        test sender = new test();
        sender.send();
        Toast.makeText(getApplicationContext(), "Message Sent!!! :)", Toast.LENGTH_LONG).show();
    } catch (Exception e) {   
        //Log.e("SendMail", e.getMessage(), e);   
    } 
}

public void exit(View view)
{
    System.exit(0);
}    
}

package com.example.test;

import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;

import android.widget.Toast;

public class test extends MainActivity
{
public void send()
{
    String host = "smtp.gmail.com";
String from = "MYUSERNAME";
String pass = "MYPASS";
try
{
Properties props = new Properties();
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");

String[] to = {"ADDRESSTOSEND@gmail.com"}; // added this line

Session session = Session.getDefaultInstance(props, null);
Message message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));

InternetAddress[] toAddress = new InternetAddress[to.length];

// To get the array of addresses
for( int i=0; i < to.length; i++ ) { // changed from a while loop
    toAddress[i] = new InternetAddress(to[i]);
}
System.out.println(Message.RecipientType.TO);

for( int i=0; i < toAddress.length; i++) { // changed from a while loop
    message.addRecipient(Message.RecipientType.TO, toAddress[i]);
}
message.setSubject("This is subject");
message.setText("Welcome to your mail");
Transport transport = session.getTransport("smtp");
transport.connect(host, from, pass);
transport.sendMessage(message, message.getAllRecipients());
transport.close();
}
catch(Exception e)
{
    Toast.makeText(getApplicationContext(), "Error" + e, Toast.LENGTH_LONG).show();
}
}
}

test.java

package com.example.test;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends Activity {
public static String EXTRA_MESSAGE = "com.example.MESSAGE";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main, menu);
    return super.onCreateOptionsMenu(menu);

}

public void sendMessage(View view)
{
    try {   
        test sender = new test();
        sender.send();
        Toast.makeText(getApplicationContext(), "Message Sent!!! :)", Toast.LENGTH_LONG).show();
    } catch (Exception e) {   
        //Log.e("SendMail", e.getMessage(), e);   
    } 
}

public void exit(View view)
{
    System.exit(0);
}    
}

package com.example.test;

import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;

import android.widget.Toast;

public class test extends MainActivity
{
public void send()
{
    String host = "smtp.gmail.com";
String from = "MYUSERNAME";
String pass = "MYPASS";
try
{
Properties props = new Properties();
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");

String[] to = {"ADDRESSTOSEND@gmail.com"}; // added this line

Session session = Session.getDefaultInstance(props, null);
Message message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));

InternetAddress[] toAddress = new InternetAddress[to.length];

// To get the array of addresses
for( int i=0; i < to.length; i++ ) { // changed from a while loop
    toAddress[i] = new InternetAddress(to[i]);
}
System.out.println(Message.RecipientType.TO);

for( int i=0; i < toAddress.length; i++) { // changed from a while loop
    message.addRecipient(Message.RecipientType.TO, toAddress[i]);
}
message.setSubject("This is subject");
message.setText("Welcome to your mail");
Transport transport = session.getTransport("smtp");
transport.connect(host, from, pass);
transport.sendMessage(message, message.getAllRecipients());
transport.close();
}
catch(Exception e)
{
    Toast.makeText(getApplicationContext(), "Error" + e, Toast.LENGTH_LONG).show();
}
}
}

package com.example.test；
导入java.util.*；
导入javax.mail.*；
导入javax.mail.internet.*；
导入android.widget.Toast；
公共类测试扩展了main活动
{
公共无效发送（）
{
String host=“smtp.gmail.com”；
字符串from=“MYUSERNAME”；
字符串pass=“MYPASS”；
尝试
{
Properties props=新属性（）；
props.put（“mail.smtp.starttls.enable”，“true”）；//添加了此行
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”）；
字符串[]到={”ADDRESSTOSEND@gmail.com“}；//添加了这一行
Session Session=Session.getDefaultInstance（props，null）；
Message Message=新的mimessage（会话）；
message.setFrom（新的InternetAddress（from））；
InternetAddress[]toAddress=新的InternetAddress[to.length]；
//获取地址数组的步骤
对于（int i=0；i

我按“发送”按钮时无法发送邮件。我已经使用xml onClick调用了sendMessage（）

eclipse中没有错误。项目编译、安装，但我没有收到邮件。当我使用

javac

尝试使用java并运行test.java时，效果很好。我的帐户里有邮件

谢谢你的帮助。

你有什么建议吗

<uses-permission android:name="android.permission.INTERNET" />

到

---

就像这样使用代码

            Intent i = new Intent(Intent.ACTION_SEND);

                        i.setType("message/rfc822");
                        i.putExtra(Intent.EXTRA_EMAIL, new String[] { "abc@gmail.com" });
                        i.putExtra(Intent.EXTRA_SUBJECT, headline);
                        i.putExtra(Intent.EXTRA_TEXT, source);
                        try {
                            activity.startActivity(Intent.createChooser(i,"Send mail..."));
                        } catch (android.content.ActivityNotFoundException ex) {
                        }

---

我还没有试过你的发送代码，但是你获取上下文的方式会引发一个空指针

在

Toast.makeText（getApplicationContext（），“Error”+e，Toast.LENGTH_LONG）.show（）中的
getApplicationContext（）
中可能会引发NullPointerException行。您不应该扩展活动以获取上下文。改为使用构造函数将上下文传递给测试类

例如：

public class Test {
    private Context cntxt;

    public Test(Context context){
        this.cntxt = context;
    }
    public void send() {
        //Code to send
        //And when you need the context you use the cntxt
        Toast.makeText(cntxt, "Error" + e, Toast.LENGTH_LONG).show()
    }
}

还要记住，声明以大写字母开头的类名是一种很好的做法和惯例。您应该将test重命名为test。
您确定正在调用
sendmages（）
？您是否尝试过以编程方式设置onclick侦听器？或者可能在
sender.send（）
上设置断点以查看实际发生的情况。调用try-in
MainActivity.java
no时，我会得到java.lang.NullPointerException。正如我提到的，我需要直接发送，而不需要弹出与用户的任何交互