我正在尝试在Android中创建邮件发送应用程序。
如果我使用:
Intent emailIntent = new Intent(android.content.Intent.ACTION_SEND);这将启动内置的Android应用程序;我试图不使用此应用程序而直接单击按钮发送邮件。
我正在尝试在Android中创建邮件发送应用程序。
如果我使用:
Intent emailIntent = new Intent(android.content.Intent.ACTION_SEND);这将启动内置的Android应用程序;我试图不使用此应用程序而直接单击按钮发送邮件。
Answers:
通过使用Gmail身份验证的JavaMail API在Android中发送电子邮件。
MailSenderActivity.java:
public class MailSenderActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        final Button send = (Button) this.findViewById(R.id.send);
        send.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                try {   
                    GMailSender sender = new GMailSender("username@gmail.com", "password");
                    sender.sendMail("This is Subject",   
                            "This is Body",   
                            "user@gmail.com",   
                            "user@yahoo.com");   
                } catch (Exception e) {   
                    Log.e("SendMail", e.getMessage(), e);   
                } 
            }
        });
    }
}GMailSender.java:
public class GMailSender extends javax.mail.Authenticator {   
    private String mailhost = "smtp.gmail.com";   
    private String user;   
    private String password;   
    private Session session;   
    static {   
        Security.addProvider(new com.provider.JSSEProvider());   
    }  
    public GMailSender(String user, String password) {   
        this.user = user;   
        this.password = password;   
        Properties props = new Properties();   
        props.setProperty("mail.transport.protocol", "smtp");   
        props.setProperty("mail.host", mailhost);   
        props.put("mail.smtp.auth", "true");   
        props.put("mail.smtp.port", "465");   
        props.put("mail.smtp.socketFactory.port", "465");   
        props.put("mail.smtp.socketFactory.class",   
                "javax.net.ssl.SSLSocketFactory");   
        props.put("mail.smtp.socketFactory.fallback", "false");   
        props.setProperty("mail.smtp.quitwait", "false");   
        session = Session.getDefaultInstance(props, this);   
    }   
    protected PasswordAuthentication getPasswordAuthentication() {   
        return new PasswordAuthentication(user, password);   
    }   
    public synchronized void sendMail(String subject, String body, String sender, String recipients) throws Exception {   
        try{
        MimeMessage message = new MimeMessage(session);   
        DataHandler handler = new DataHandler(new ByteArrayDataSource(body.getBytes(), "text/plain"));   
        message.setSender(new InternetAddress(sender));   
        message.setSubject(subject);   
        message.setDataHandler(handler);   
        if (recipients.indexOf(',') > 0)   
            message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(recipients));   
        else  
            message.setRecipient(Message.RecipientType.TO, new InternetAddress(recipients));   
        Transport.send(message);   
        }catch(Exception e){
        }
    }   
    public class ByteArrayDataSource implements DataSource {   
        private byte[] data;   
        private String type;   
        public ByteArrayDataSource(byte[] data, String type) {   
            super();   
            this.data = data;   
            this.type = type;   
        }   
        public ByteArrayDataSource(byte[] data) {   
            super();   
            this.data = data;   
        }   
        public void setType(String type) {   
            this.type = type;   
        }   
        public String getContentType() {   
            if (type == null)   
                return "application/octet-stream";   
            else  
                return type;   
        }   
        public InputStream getInputStream() throws IOException {   
            return new ByteArrayInputStream(data);   
        }   
        public String getName() {   
            return "ByteArrayDataSource";   
        }   
        public OutputStream getOutputStream() throws IOException {   
            throw new IOException("Not Supported");   
        }   
    }   
}  JSSEProvider.java:
/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
/**
 * @author Alexander Y. Kleymenov
 * @version $Revision$
 */
import java.security.AccessController;
import java.security.Provider;
public final class JSSEProvider extends Provider {
    public JSSEProvider() {
        super("HarmonyJSSE", 1.0, "Harmony JSSE Provider");
        AccessController.doPrivileged(new java.security.PrivilegedAction<Void>() {
            public Void run() {
                put("SSLContext.TLS",
                        "org.apache.harmony.xnet.provider.jsse.SSLContextImpl");
                put("Alg.Alias.SSLContext.TLSv1", "TLS");
                put("KeyManagerFactory.X509",
                        "org.apache.harmony.xnet.provider.jsse.KeyManagerFactoryImpl");
                put("TrustManagerFactory.X509",
                        "org.apache.harmony.xnet.provider.jsse.TrustManagerFactoryImpl");
                return null;
            }
        });
    }
}在以下链接中添加3个jar至您的Android项目
并且不要忘记在清单中添加以下行:
<uses-permission android:name="android.permission.INTERNET" />只需单击下面的链接即可更改安全性较低的应用程序的帐户访问权限 https://www.google.com/settings/security/lesssecureapps
运行该项目,并检查您的收件人邮件帐户中的邮件。干杯!
PS并且不要忘记,您无法通过android中的任何Activity进行网络操作。因此,建议使用AsyncTask或IntentService避免主线程网络异常。
感谢您提供宝贵的信息。代码运行正常。我还可以通过添加以下代码来添加附件。
private Multipart _multipart; 
_multipart = new MimeMultipart(); 
public void addAttachment(String filename,String subject) throws Exception { 
    BodyPart messageBodyPart = new MimeBodyPart(); 
    DataSource source = new FileDataSource(filename); 
    messageBodyPart.setDataHandler(new DataHandler(source)); 
    messageBodyPart.setFileName(filename); 
    _multipart.addBodyPart(messageBodyPart);
    BodyPart messageBodyPart2 = new MimeBodyPart(); 
    messageBodyPart2.setText(subject); 
    _multipart.addBodyPart(messageBodyPart2); 
} 
message.setContent(_multipart);filename此处的变量,您必须指定文件路径。例如:String path = Environment.getExternalStorageDirectory().getPath() + "/temp_share.jpg";
                    您可以使用JavaMail API处理电子邮件任务。JavaMail API中提供了JavaMail API,其jar也可以下载。遗憾的是,由于它使用的AWT组件在Android中完全不兼容,因此无法直接在Android应用程序中使用。
您可以在以下位置找到JavaMail的Android端口:http : //code.google.com/p/javamail-android/
将罐子添加到您的应用程序并使用SMTP方法
eu.ocathain.com.sun.mail:javax.mail:1.5.2
                    为了帮助那些使用SDK Target> 9的人获得主线程网络异常。这在上面使用了droopie的代码,但是对于任何人都将类似地工作。
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy); 
android.os.NetworkOnMainThreadException您可以如下使用AsyncTask
public void onClickMail(View view) {
    new SendEmailAsyncTask().execute();
}
class SendEmailAsyncTask extends AsyncTask <Void, Void, Boolean> {
    Mail m = new Mail("from@gmail.com", "my password");
    public SendEmailAsyncTask() {
        if (BuildConfig.DEBUG) Log.v(SendEmailAsyncTask.class.getName(), "SendEmailAsyncTask()");
        String[] toArr = { "to mail@gmail.com"};
        m.setTo(toArr);
        m.setFrom("from mail@gmail.com");
        m.setSubject("Email from Android");
        m.setBody("body.");
    }
    @Override
    protected Boolean doInBackground(Void... params) {
        if (BuildConfig.DEBUG) Log.v(SendEmailAsyncTask.class.getName(), "doInBackground()");
        try {
            m.send();
            return true;
        } catch (AuthenticationFailedException e) {
            Log.e(SendEmailAsyncTask.class.getName(), "Bad account details");
            e.printStackTrace();
            return false;
        } catch (MessagingException e) {
            Log.e(SendEmailAsyncTask.class.getName(), m.getTo(null) + "failed");
            e.printStackTrace();
            return false;
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }100%带有演示的工作代码您也可以使用此答案发送多封电子邮件。
在这里下载项目
步骤1: 下载mail,activation,additional jar文件,并在android studio中添加您的项目libs文件夹。我添加了一个屏幕截图,请参见下面的下载链接
使用gmail登录(使用您的邮件中的邮件)和“ 打开” 切换按钮LINK
大多数人会忘记这一步,我希望您不会。
步骤2: 完成这个程序后。将此类复制并粘贴到您的项目中。
GMail.java
import android.util.Log;
import java.io.UnsupportedEncodingException;
import java.util.List;
import java.util.Properties;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
public class GMail {
    final String emailPort = "587";// gmail's smtp port
    final String smtpAuth = "true";
    final String starttls = "true";
    final String emailHost = "smtp.gmail.com";
    String fromEmail;
    String fromPassword;
    List<String> toEmailList;
    String emailSubject;
    String emailBody;
    Properties emailProperties;
    Session mailSession;
    MimeMessage emailMessage;
    public GMail() {
    }
    public GMail(String fromEmail, String fromPassword,
            List<String> toEmailList, String emailSubject, String emailBody) {
        this.fromEmail = fromEmail;
        this.fromPassword = fromPassword;
        this.toEmailList = toEmailList;
        this.emailSubject = emailSubject;
        this.emailBody = emailBody;
        emailProperties = System.getProperties();
        emailProperties.put("mail.smtp.port", emailPort);
        emailProperties.put("mail.smtp.auth", smtpAuth);
        emailProperties.put("mail.smtp.starttls.enable", starttls);
        Log.i("GMail", "Mail server properties set.");
    }
    public MimeMessage createEmailMessage() throws AddressException,
            MessagingException, UnsupportedEncodingException {
        mailSession = Session.getDefaultInstance(emailProperties, null);
        emailMessage = new MimeMessage(mailSession);
        emailMessage.setFrom(new InternetAddress(fromEmail, fromEmail));
        for (String toEmail : toEmailList) {
            Log.i("GMail", "toEmail: " + toEmail);
            emailMessage.addRecipient(Message.RecipientType.TO,
                    new InternetAddress(toEmail));
        }
        emailMessage.setSubject(emailSubject);
        emailMessage.setContent(emailBody, "text/html");// for a html email
        // emailMessage.setText(emailBody);// for a text email
        Log.i("GMail", "Email Message created.");
        return emailMessage;
    }
    public void sendEmail() throws AddressException, MessagingException {
        Transport transport = mailSession.getTransport("smtp");
        transport.connect(emailHost, fromEmail, fromPassword);
        Log.i("GMail", "allrecipients: " + emailMessage.getAllRecipients());
        transport.sendMessage(emailMessage, emailMessage.getAllRecipients());
        transport.close();
        Log.i("GMail", "Email sent successfully.");
    }
}SendMailTask.java
import android.app.Activity;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.util.Log;
import java.util.List;
public class SendMailTask extends AsyncTask {
    private ProgressDialog statusDialog;
    private Activity sendMailActivity;
    public SendMailTask(Activity activity) {
        sendMailActivity = activity;
    }
    protected void onPreExecute() {
        statusDialog = new ProgressDialog(sendMailActivity);
        statusDialog.setMessage("Getting ready...");
        statusDialog.setIndeterminate(false);
        statusDialog.setCancelable(false);
        statusDialog.show();
    }
    @Override
    protected Object doInBackground(Object... args) {
        try {
            Log.i("SendMailTask", "About to instantiate GMail...");
            publishProgress("Processing input....");
            GMail androidEmail = new GMail(args[0].toString(),
                    args[1].toString(), (List) args[2], args[3].toString(),
                    args[4].toString());
            publishProgress("Preparing mail message....");
            androidEmail.createEmailMessage();
            publishProgress("Sending email....");
            androidEmail.sendEmail();
            publishProgress("Email Sent.");
            Log.i("SendMailTask", "Mail Sent.");
        } catch (Exception e) {
            publishProgress(e.getMessage());
            Log.e("SendMailTask", e.getMessage(), e);
        }
        return null;
    }
    @Override
    public void onProgressUpdate(Object... values) {
        statusDialog.setMessage(values[0].toString());
    }
    @Override
    public void onPostExecute(Object result) {
        statusDialog.dismiss();
    }
}步骤3: 现在,您可以根据需要更改此类,也可以使用该类发送多个邮件。我同时提供xml和java文件。
activity_mail.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingLeft="20dp"
    android:paddingRight="20dp"
    android:paddingTop="30dp">
    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingTop="10dp"
        android:text="From Email" />
    <EditText
        android:id="@+id/editText1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#FFFFFF"
        android:cursorVisible="true"
        android:editable="true"
        android:ems="10"
        android:enabled="true"
        android:inputType="textEmailAddress"
        android:padding="5dp"
        android:textColor="#000000">
        <requestFocus />
    </EditText>
    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingTop="10dp"
        android:text="Password (For from email)" />
    <EditText
        android:id="@+id/editText2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#FFFFFF"
        android:ems="10"
        android:inputType="textPassword"
        android:padding="5dp"
        android:textColor="#000000" />
    <TextView
        android:id="@+id/textView3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingTop="10dp"
        android:text="To Email" />
    <EditText
        android:id="@+id/editText3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#ffffff"
        android:ems="10"
        android:inputType="textEmailAddress"
        android:padding="5dp"
        android:textColor="#000000" />
    <TextView
        android:id="@+id/textView4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingTop="10dp"
        android:text="Subject" />
    <EditText
        android:id="@+id/editText4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#ffffff"
        android:ems="10"
        android:padding="5dp"
        android:textColor="#000000" />
    <TextView
        android:id="@+id/textView5"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingTop="10dp"
        android:text="Body" />
    <EditText
        android:id="@+id/editText5"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#ffffff"
        android:ems="10"
        android:inputType="textMultiLine"
        android:padding="35dp"
        android:textColor="#000000" />
    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Send Email" />
</LinearLayout>SendMailActivity.java
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.util.Arrays;
import java.util.List;
public class SendMailActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final Button send = (Button) this.findViewById(R.id.button1);
        send.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                Log.i("SendMailActivity", "Send Button Clicked.");
                String fromEmail = ((TextView) findViewById(R.id.editText1))
                        .getText().toString();
                String fromPassword = ((TextView) findViewById(R.id.editText2))
                        .getText().toString();
                String toEmails = ((TextView) findViewById(R.id.editText3))
                        .getText().toString();
                List<String> toEmailList = Arrays.asList(toEmails
                        .split("\\s*,\\s*"));
                Log.i("SendMailActivity", "To List: " + toEmailList);
                String emailSubject = ((TextView) findViewById(R.id.editText4))
                        .getText().toString();
                String emailBody = ((TextView) findViewById(R.id.editText5))
                        .getText().toString();
                new SendMailTask(SendMailActivity.this).execute(fromEmail,
                        fromPassword, toEmailList, emailSubject, emailBody);
            }
        });
    }
}注意不要忘记在AndroidManifest.xml文件中添加互联网权限
<uses-permission android:name="android.permission.INTERNET"/>
希望它能成功,如果不行,那就在下面留言。
使用SMTP是一种可行的方法,其他方法已经指出了实现方法。只需注意,在执行此操作时,您将完全避开内置的邮件应用程序,并且必须在代码中静态提供SMTP服务器的地址,该服务器的用户名和密码,或者从用户那里查询它。 。
另一种方法是使用简单的服务器端脚本(例如php),该脚本采用一些URL参数并使用它们发送邮件。这样,您只需要从设备发出HTTP请求(使用内置库就可以轻松实现),而无需在设备上存储SMTP登录数据。与直接使用SMTP相比,这是另一种间接方式,但是由于发出HTTP请求和从PHP发送邮件非常容易,因此它甚至可能比直接方式更简单。
如果邮件将从他已经在电话中注册的用户默认邮件帐户发送,则您必须采取其他方法。如果您有足够的时间和经验,则可能需要检查Android Email应用程序的源代码,以查看它是否提供了一些无需用户干预即可发送邮件的入口点(我不知道,但也许有一个)。
也许您甚至找到了一种查询用户帐户详细信息的方法(以便可以将其用于SMTP),尽管我高度怀疑这样做是否可行,因为这将带来巨大的安全风险,并且Android的构建相当安全。
这是一个适用于我的替代版本,并具有附件(已在上方发布,但与源链接不同,是完整版本,人们发布后由于缺少数据而无法使其正常工作)
import java.util.Date; 
import java.util.Properties; 
import javax.activation.CommandMap; 
import javax.activation.DataHandler; 
import javax.activation.DataSource; 
import javax.activation.FileDataSource; 
import javax.activation.MailcapCommandMap; 
import javax.mail.BodyPart; 
import javax.mail.Multipart; 
import javax.mail.PasswordAuthentication; 
import javax.mail.Session; 
import javax.mail.Transport; 
import javax.mail.internet.InternetAddress; 
import javax.mail.internet.MimeBodyPart; 
import javax.mail.internet.MimeMessage; 
import javax.mail.internet.MimeMultipart; 
public class Mail extends javax.mail.Authenticator { 
  private String _user; 
  private String _pass; 
  private String[] _to; 
  private String _from; 
  private String _port; 
  private String _sport; 
  private String _host; 
  private String _subject; 
  private String _body; 
  private boolean _auth; 
  private boolean _debuggable; 
  private Multipart _multipart; 
  public Mail() { 
    _host = "smtp.gmail.com"; // default smtp server 
    _port = "465"; // default smtp port 
    _sport = "465"; // default socketfactory port 
    _user = ""; // username 
    _pass = ""; // password 
    _from = ""; // email sent from 
    _subject = ""; // email subject 
    _body = ""; // email body 
    _debuggable = false; // debug mode on or off - default off 
    _auth = true; // smtp authentication - default on 
    _multipart = new MimeMultipart(); 
    // There is something wrong with MailCap, javamail can not find a handler for the multipart/mixed part, so this bit needs to be added. 
    MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap(); 
    mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html"); 
    mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml"); 
    mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain"); 
    mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed"); 
    mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822"); 
    CommandMap.setDefaultCommandMap(mc); 
  } 
  public Mail(String user, String pass) { 
    this(); 
    _user = user; 
    _pass = pass; 
  } 
  public boolean send() throws Exception { 
    Properties props = _setProperties(); 
    if(!_user.equals("") && !_pass.equals("") && _to.length > 0 && !_from.equals("") && !_subject.equals("") && !_body.equals("")) { 
      Session session = Session.getInstance(props, this); 
      MimeMessage msg = new MimeMessage(session); 
      msg.setFrom(new InternetAddress(_from)); 
      InternetAddress[] addressTo = new InternetAddress[_to.length]; 
      for (int i = 0; i < _to.length; i++) { 
        addressTo[i] = new InternetAddress(_to[i]); 
      } 
        msg.setRecipients(MimeMessage.RecipientType.TO, addressTo); 
      msg.setSubject(_subject); 
      msg.setSentDate(new Date()); 
      // setup message body 
      BodyPart messageBodyPart = new MimeBodyPart(); 
      messageBodyPart.setText(_body); 
      _multipart.addBodyPart(messageBodyPart); 
      // Put parts in message 
      msg.setContent(_multipart); 
      // send email 
      Transport.send(msg); 
      return true; 
    } else { 
      return false; 
    } 
  } 
  public void addAttachment(String filename) throws Exception { 
    BodyPart messageBodyPart = new MimeBodyPart(); 
    DataSource source = new FileDataSource(filename); 
    messageBodyPart.setDataHandler(new DataHandler(source)); 
    messageBodyPart.setFileName(filename); 
    _multipart.addBodyPart(messageBodyPart); 
  } 
  @Override 
  public PasswordAuthentication getPasswordAuthentication() { 
    return new PasswordAuthentication(_user, _pass); 
  } 
  private Properties _setProperties() { 
    Properties props = new Properties(); 
    props.put("mail.smtp.host", _host); 
    if(_debuggable) { 
      props.put("mail.debug", "true"); 
    } 
    if(_auth) { 
      props.put("mail.smtp.auth", "true"); 
    } 
    props.put("mail.smtp.port", _port); 
    props.put("mail.smtp.socketFactory.port", _sport); 
    props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory"); 
    props.put("mail.smtp.socketFactory.fallback", "false"); 
    return props; 
  } 
  // the getters and setters 
  public String getBody() { 
    return _body; 
  } 
  public void setBody(String _body) { 
    this._body = _body; 
  }
  public void setTo(String[] toArr) {
      // TODO Auto-generated method stub
      this._to=toArr;
  }
  public void setFrom(String string) {
      // TODO Auto-generated method stub
      this._from=string;
  }
  public void setSubject(String string) {
      // TODO Auto-generated method stub
      this._subject=string;
  }  
  // more of the getters and setters ….. 
}并在活动中称呼它...
@Override 
public void onCreate(Bundle icicle) { 
  super.onCreate(icicle); 
  setContentView(R.layout.main); 
  Button addImage = (Button) findViewById(R.id.send_email); 
  addImage.setOnClickListener(new View.OnClickListener() { 
    public void onClick(View view) { 
      Mail m = new Mail("gmailusername@gmail.com", "password"); 
      String[] toArr = {"bla@bla.com", "lala@lala.com"}; 
      m.setTo(toArr); 
      m.setFrom("wooo@wooo.com"); 
      m.setSubject("This is an email sent using my Mail JavaMail wrapper from an Android device."); 
      m.setBody("Email body."); 
      try { 
        m.addAttachment("/sdcard/filelocation"); 
        if(m.send()) { 
          Toast.makeText(MailApp.this, "Email was sent successfully.", Toast.LENGTH_LONG).show(); 
        } else { 
          Toast.makeText(MailApp.this, "Email was not sent.", Toast.LENGTH_LONG).show(); 
        } 
      } catch(Exception e) { 
        //Toast.makeText(MailApp.this, "There was a problem sending the email.", Toast.LENGTH_LONG).show(); 
        Log.e("MailApp", "Could not send email", e); 
      } 
    } 
  }); 
} Could not send email android.os.NetworkOnMainThreadException at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork该问题,有必要查看此解决方案stackoverflow.com/questions/25093546/…–
                    GmailBackground是一个小型图书馆,可以在后台发送电子邮件而无需用户干预:
用法:
    BackgroundMail.newBuilder(this)
            .withUsername("username@gmail.com")
            .withPassword("password12345")
            .withMailto("toemail@gmail.com")
            .withType(BackgroundMail.TYPE_PLAIN)
            .withSubject("this is the subject")
            .withBody("this is the body")
            .withOnSuccessCallback(new BackgroundMail.OnSuccessCallback() {
                @Override
                public void onSuccess() {
                    //do some magic
                }
            })
            .withOnFailCallback(new BackgroundMail.OnFailCallback() {
                @Override
                public void onFail() {
                    //do some magic
                }
            })
            .send();组态:
repositories {
    // ...
    maven { url "https://jitpack.io" }
 }
 dependencies {
            compile 'com.github.yesidlazaro:GmailBackground:1.2.0'
    }权限:
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>同样对于附件,您需要设置READ_EXTERNAL_STORAGE权限:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>(我已经自己测试过)
如果使用“ smtp.gmail.com”作为默认的smtp服务器,则发出警告。
由于过分热心的“可疑活动”政策,Google会强迫您频繁更改链接的电子邮件帐户密码。本质上,它将短时间内来自不同国家的重复smtp请求视为“可疑活动”。因为他们假设您(电子邮件帐户持有人)一次只能在一个国家/地区。
当Google系统检测到“可疑活动”时,除非您更改密码,否则它将阻止发送进一步的电子邮件。由于您会将密码硬编码到应用程序中,因此每次发生这种情况时都必须重新释放该应用程序,这并不理想。这对我来说一周发生3次,我什至将密码存储在另一台服务器上,并在每次Google强迫我更改密码时动态获取密码。
因此,我建议使用许多免费的smtp提供程序之一而不是“ smtp.gmail.com”来避免此安全问题。使用相同的代码,但将“ smtp.gmail.com”更改为新的smtp转发主机。
suspicioud activity问题吗?
                    编辑:JavaMail 1.5.5 声称支持Android,因此您不需要其他任何东西。
我已经将最新的JavaMail(1.5.4)移植到了Android。它在Maven Central中可用,只需将以下内容添加到build.gradle~~
compile 'eu.ocathain.com.sun.mail:javax.mail:1.5.4'然后,您可以按照官方教程进行操作。
源代码可在此处获取:https://bitbucket.org/artbristol/javamail-forked-android
我为需要帮助的其他人找到了更短的选择。代码是:
package com.example.mail;
import java.util.Properties;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
public class SendMailTLS {
    public static void main(String[] args) {
        final String username = "username@gmail.com";
        final String password = "password";
        Properties props = new Properties();
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.host", "smtp.gmail.com");
        props.put("mail.smtp.port", "587");
        Session session = Session.getInstance(props,
          new javax.mail.Authenticator() {
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication("username", "password");
            }
          });
        try {
            Message message = new MimeMessage(session);
            message.setFrom(new InternetAddress("from-email@gmail.com"));
            message.setRecipients(Message.RecipientType.TO,
                InternetAddress.parse("to-email@gmail.com"));
            message.setSubject("Testing Subject");
            message.setText("Dear Mail Crawler,"
                + "\n\n No spam to my email, please!");
            Transport.send(message);
            System.out.println("Done");
        } catch (MessagingException e) {
            throw new RuntimeException(e);
        }
    }
}希望这可以帮助!祝好运!
那些ClassDefNotFoundError试图将这三个jar文件移动到您项目的lib文件夹中的人,对我有用!
用于发送带有附件的邮件。
public class SendAttachment{
                    public static void main(String [] args){ 
             //to address
                    String to="abc@abc.com";//change accordingly
                    //from address
                    final String user="efg@efg.com";//change accordingly
                    final String password="password";//change accordingly 
                     MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap();
                   mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html");
                  mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml");
                  mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain");
                  mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed");
                  mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822");
                  CommandMap.setDefaultCommandMap(mc); 
                  //1) get the session object   
                  Properties properties = System.getProperties();
                  properties.put("mail.smtp.port", "465"); 
                  properties.put("mail.smtp.host", "smtp.gmail.com");
                    properties.put("mail.smtp.socketFactory.port", "465");
                    properties.put("mail.smtp.socketFactory.class",
                            "javax.net.ssl.SSLSocketFactory");
                    properties.put("mail.smtp.auth", "true");
                    properties.put("mail.smtp.port", "465");
                  Session session = Session.getDefaultInstance(properties,
                   new javax.mail.Authenticator() {
                   protected PasswordAuthentication getPasswordAuthentication() {
                   return new PasswordAuthentication(user,password);
                   }
                  });
                  //2) compose message   
                  try{ 
                    MimeMessage message = new MimeMessage(session);
                    message.setFrom(new InternetAddress(user));
                    message.addRecipient(Message.RecipientType.TO,new InternetAddress(to));
                    message.setSubject("Hii"); 
                    //3) create MimeBodyPart object and set your message content    
                    BodyPart messageBodyPart1 = new MimeBodyPart();
                    messageBodyPart1.setText("How is This"); 
                    //4) create new MimeBodyPart object and set DataHandler object to this object    
                    MimeBodyPart messageBodyPart2 = new MimeBodyPart();
                //Location of file to be attached
                    String filename = Environment.getExternalStorageDirectory().getPath()+"/R2832.zip";//change accordingly
                    DataSource source = new FileDataSource(filename);
                    messageBodyPart2.setDataHandler(new DataHandler(source));
                    messageBodyPart2.setFileName("Hello"); 
                    //5) create Multipart object and add MimeBodyPart objects to this object    
                    Multipart multipart = new MimeMultipart();
                    multipart.addBodyPart(messageBodyPart1);
                    multipart.addBodyPart(messageBodyPart2); 
                    //6) set the multiplart object to the message object
                    message.setContent(multipart ); 
                    //7) send message 
                    Transport.send(message); 
                   System.out.println("MESSAGE SENT....");
                   }catch (MessagingException ex) {ex.printStackTrace();}
                  }
                }您是否考虑过使用Apache Commons Net?从3.3版本开始,只有一个jar(您可以使用gradle或maven依赖它)就可以完成:http ://blog.dahanne.net/2013/06/17/sending-a-mail-in-java- 和android-with-apache-commons-net /
在没有用户干预的情况下,您可以发送以下内容:
从客户端APK发送电子邮件。在这里,mail.jar,activation.jar是发送Java电子邮件所必需的。如果添加了这些jar,则可能会增加APK大小。
另外,您可以在服务器端代码中使用Web服务,该代码将使用相同的mail.jar和activation.jar发送电子邮件。您可以通过asynctask调用Web服务并发送电子邮件。引用相同的链接。
(但是,您将需要知道邮件帐户的凭据)
如果要求您将jar库保持尽可能小,则可以分别包含SMTP / POP3 / IMAP函数,以避免“ dex中的方法过多”的问题。
您可以从javanet网页中选择所需的jar库,例如,mailapi.jar + imap.jar可以使您以imap协议访问icloud,hotmail邮件服务器。(借助于Additional.jar和Activation.jar)
我尝试使用@Vinayak B提交的代码。但是我收到一个错误消息:没有smtp的提供程序
我创建了这个新问题,以了解更多信息HERE
毕竟我自己就能解决它。我必须使用其他mail.jar, 并且必须确保启用了“ 对不太安全的应用程序的访问 ”。
我希望这对有相同问题的任何人有所帮助。完成此操作后,这部分代码也可以在Google Glass上运行。
其他答案中提供的所有代码都是正确的,并且工作正常,但有点混乱,因此我决定发布一个库(尽管仍在开发中)以更轻松地使用它:AndroidMail。
您只需要创建一个MailSender,构建一个邮件并将其发送(已经使用AsyncTask在后台处理)。
MailSender mailSender = new MailSender(email, password);
Mail.MailBuilder builder = new Mail.MailBuilder();
Mail mail = builder
    .setSender(senderMail)
    .addRecipient(new Recipient(recipient))
    .setText("Hello")
    .build();
mailSender.sendMail(mail);您可以收到有关已发送电子邮件的通知,它还支持不同的收件人类型(TO,CC和BCC),附件和html:
MailSender mailSender = new MailSender(email, password);
Mail.MailBuilder builder = new Mail.MailBuilder();
Mail mail = builder
    .setSender(senderMail)
    .addRecipient(new Recipient(recipient))
    .addRecipient(new Recipient(Recipient.TYPE.CC, recipientCC))
    .setText("Hello")
    .setHtml("<h1 style=\"color:red;\">Hello</h1>")
    .addAttachment(new Attachment(filePath, fileName))
    .build();
mailSender.sendMail(mail, new MailSender.OnMailSentListener() {
    @Override
    public void onSuccess() {
        // mail sent!
    }
    @Override
    public void onError(Exception error) {
        // something bad happened :(
    }
});您可以通过Gradle或Maven获得它:
compile 'it.enricocandino:androidmail:1.0.0-SNAPSHOT'如果您有任何问题,请告诉我!:)
这里有很多解决方案。但是,我认为我们必须更改GMail的配置,以允许从不太安全的设备进行访问。转到下面的链接并启用它。这个对我有用
 Add jar files mail.jar,activation.jar,additionnal.jar
 String sub="Thank you for your online registration" ; 
 Mail m = new Mail("emailid", "password"); 
 String[] toArr = {"ekkatrainfo@gmail.com",sEmailId};
 m.setFrom("ekkatrainfo@gmail.com"); 
     m.setTo(toArr);
     m.setSubject(sub);
    m.setBody(msg);
                     try{
                            if(m.send()) { 
                            } else { 
                            } 
                          } catch(Exception e) { 
                            Log.e("MailApp", "Could not send email", e); 
                          } 
  package com.example.ekktra;
   import java.util.Date;
   import java.util.Properties;
   import javax.activation.CommandMap;
   import javax.activation.DataHandler;
   import javax.activation.DataSource;
   import javax.activation.FileDataSource;
   import javax.activation.MailcapCommandMap;
   import javax.mail.BodyPart;
   import javax.mail.Multipart;
   import javax.mail.PasswordAuthentication;
   import javax.mail.Session;
   import javax.mail.Transport;
   import javax.mail.internet.InternetAddress;
   import javax.mail.internet.MimeBodyPart;
   import javax.mail.internet.MimeMessage;
   import javax.mail.internet.MimeMultipart;
   public class Mail extends javax.mail.Authenticator { 
     private String _user; 
     private String _pass; 
     private String[] _to; 
     private String _from; 
     private String _port; 
     private String _sport; 
     private String _host; 
     private String _subject; 
     private String _body; 
     private boolean _auth; 
     private boolean _debuggable; 
     private Multipart _multipart; 
   public Mail() { 
      _host = "smtp.gmail.com"; // default smtp server 
      _port = "465"; // default smtp port 
      _sport = "465"; // default socketfactory port 
      _user = ""; // username 
      _pass = ""; // password 
      _from = ""; // email sent from 
      _subject = ""; // email subject 
      _body = ""; // email body 
      _debuggable = false; // debug mode on or off - default off 
      _auth = true; // smtp authentication - default on 
      _multipart = new MimeMultipart(); 
      // There is something wrong with MailCap, javamail can not find a handler for the        multipart/mixed part, so this bit needs to be added. 
      MailcapCommandMap mc = (MailcapCommandMap) CommandMap.getDefaultCommandMap(); 
   mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html"); 
   mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml"); 
   mc.addMailcap("text/plain;; x-java-content-  handler=com.sun.mail.handlers.text_plain"); 
   mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed"); 
   mc.addMailcap("message/rfc822;; x-java-content- handler=com.sun.mail.handlers.message_rfc822"); 
    CommandMap.setDefaultCommandMap(mc); 
   } 
 public Mail(String user, String pass) { 
  this(); 
  _user = user; 
   _pass = pass; 
 } 
public boolean send() throws Exception { 
   Properties props = _setProperties(); 
  if(!_user.equals("") && !_pass.equals("") && _to.length > 0 && !_from.equals("") &&   !_subject.equals("") /*&& !_body.equals("")*/) { 
    Session session = Session.getInstance(props, this); 
    MimeMessage msg = new MimeMessage(session); 
     msg.setFrom(new InternetAddress(_from)); 
    InternetAddress[] addressTo = new InternetAddress[_to.length]; 
     for (int i = 0; i < _to.length; i++) { 
      addressTo[i] = new InternetAddress(_to[i]); 
    } 
      msg.setRecipients(MimeMessage.RecipientType.TO, addressTo); 
    msg.setSubject(_subject); 
    msg.setSentDate(new Date()); 
  // setup message body 
  BodyPart messageBodyPart = new MimeBodyPart(); 
    messageBodyPart.setText(_body); 
    _multipart.addBodyPart(messageBodyPart); 
     // Put parts in message 
    msg.setContent(_multipart); 
    // send email 
    Transport.send(msg); 
    return true; 
   } else { 
     return false; 
   } 
  } 
   public void addAttachment(String filename) throws Exception { 
    BodyPart messageBodyPart = new MimeBodyPart(); 
    DataSource source = new FileDataSource(filename); 
      messageBodyPart.setDataHandler(new DataHandler(source)); 
    messageBodyPart.setFileName(filename); 
   _multipart.addBodyPart(messageBodyPart); 
 } 
  @Override 
  public PasswordAuthentication getPasswordAuthentication() { 
     return new PasswordAuthentication(_user, _pass); 
  } 
   private Properties _setProperties() { 
   Properties props = new Properties(); 
    props.put("mail.smtp.host", _host); 
  if(_debuggable) { 
    props.put("mail.debug", "true"); 
  } 
  if(_auth) { 
    props.put("mail.smtp.auth", "true"); 
   } 
    props.put("mail.smtp.port", _port); 
    props.put("mail.smtp.socketFactory.port", _sport); 
    props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory"); 
    props.put("mail.smtp.socketFactory.fallback", "false"); 
    return props; 
   } 
   // the getters and setters 
  public String getBody() { 
   return _body; 
 } 
 public void setBody(String _body) { 
  this._body = _body; 
 }
  public void setTo(String[] toArr) {
     // TODO Auto-generated method stub
    this._to=toArr;
 }
public void setFrom(String string) {
    // TODO Auto-generated method stub
    this._from=string;
}
 public void setSubject(String string) {
    // TODO Auto-generated method stub
    this._subject=string;
  }  
   }使用Kotlin以编程方式发送电子邮件。
我还发现此电子邮件POP服务列表确实很有帮助:
如何使用:
    val auth = EmailService.UserPassAuthenticator("you@gmail.com", "yourPassword")
    val to = listOf(InternetAddress("to@email.com"))
    val from = InternetAddress("you@gmail.com")
    val email = EmailService.Email(auth, to, from, "Test Subject", "Hello Body World")
    val emailService = EmailService("smtp.gmail.com", 465)
    GlobalScope.launch { // or however you do background threads
        emailService.send(email)
    }编码:
import java.util.*
import javax.mail.*
import javax.mail.internet.InternetAddress
import javax.mail.internet.MimeBodyPart
import javax.mail.internet.MimeMessage
import javax.mail.internet.MimeMultipart
class EmailService(private val server: String, private val port: Int) {
    data class Email(
        val auth: Authenticator,
        val toList: List<InternetAddress>,
        val from: Address,
        val subject: String,
        val body: String
    )
    class UserPassAuthenticator(private val username: String, private val password: String) : Authenticator() {
        override fun getPasswordAuthentication(): PasswordAuthentication {
            return PasswordAuthentication(username, password)
        }
    }
    fun send(email: Email) {
        val props = Properties()
        props["mail.smtp.auth"] = "true"
        props["mail.user"] = email.from
        props["mail.smtp.host"] = server
        props["mail.smtp.port"] = port
        props["mail.smtp.starttls.enable"] = "true"
        props["mail.smtp.ssl.trust"] = server
        props["mail.mime.charset"] = "UTF-8"
        val msg: Message = MimeMessage(Session.getDefaultInstance(props, email.auth))
        msg.setFrom(email.from)
        msg.sentDate = Calendar.getInstance().time
        msg.setRecipients(Message.RecipientType.TO, email.toList.toTypedArray())
//      msg.setRecipients(Message.RecipientType.CC, email.ccList.toTypedArray())
//      msg.setRecipients(Message.RecipientType.BCC, email.bccList.toTypedArray())
        msg.replyTo = arrayOf(email.from)
        msg.addHeader("X-Mailer", CLIENT_NAME)
        msg.addHeader("Precedence", "bulk")
        msg.subject = email.subject
        msg.setContent(MimeMultipart().apply {
            addBodyPart(MimeBodyPart().apply {
                setText(email.body, "iso-8859-1")
                //setContent(email.htmlBody, "text/html; charset=UTF-8")
            })
        })
        Transport.send(msg)
    }
    companion object {
        const val CLIENT_NAME = "Android StackOverflow programmatic email"
    }
}摇篮:
dependencies {
    implementation 'com.sun.mail:android-mail:1.6.4'
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.3"
}AndroidManifest:
<uses-permission name="android.permission.INTERNET" />要添加附件,请不要忘记添加。
MailcapCommandMap mc = (MailcapCommandMap) CommandMap
            .getDefaultCommandMap();
    mc.addMailcap("text/html;; x-java-content-handler=com.sun.mail.handlers.text_html");
    mc.addMailcap("text/xml;; x-java-content-handler=com.sun.mail.handlers.text_xml");
    mc.addMailcap("text/plain;; x-java-content-handler=com.sun.mail.handlers.text_plain");
    mc.addMailcap("multipart/*;; x-java-content-handler=com.sun.mail.handlers.multipart_mixed");
    mc.addMailcap("message/rfc822;; x-java-content-handler=com.sun.mail.handlers.message_rfc822");
    CommandMap.setDefaultCommandMap(mc);