在 Android 中使用 Gmail API 发送带附件的电子邮件(execute() 挂起)

Sending email with attachments using Gmail API in Android (execute() hangs)

只要附件很小，一切似乎都可以正常工作。
但是，当我尝试附加一个更大的文件(例如 7MB)时，Send 的 execute() 方法只是挂起。
我尝试查看文档，如果我理解正确，我应该使用实际执行 upload 的 Send API，但是，我不知道应该在哪里提供这些参数。
这是电子邮件生成方法：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46

public MimeMessage toMimeMessage(String from, Context context) throws MessagingException {
Properties props = new Properties();
Session session = Session.getDefaultInstance(props, null);

MimeMessage mimeMessage = new MimeMessage(session);

mimeMessage.setFrom(new InternetAddress(from));
mimeMessage.addRecipient(javax.mail.Message.RecipientType.TO, new InternetAddress(recipient));
mimeMessage.setSubject(subject);

MimeBodyPart mimeBodyText = new MimeBodyPart();
mimeBodyText.setContent(body,"text/html");
mimeBodyText.setHeader("Content-Type","text/plain; charset="UTF-8"");

Multipart mp = new MimeMultipart();
mp.addBodyPart(mimeBodyText);

if (attachments != null && attachments.size() > 0) {
MimeBodyPart mimeBodyAttachments = new MimeBodyPart();
for (Uri uri : attachments) {
String fileName = UriUtils.getFileName(uri, context);
String mimeType = UriUtils.getMimeType(uri, context);
Log.d(TAG,"Generating file info, uri=" + uri.getPath() +", mimeType=" + mimeType);
FileInputStream is = UriUtils.generateFileInfo(context, uri, mimeType);
if (is == null) {
throw new MessagingException("Failed to get file for uri=" + uri.getPath());
}
try
{
DataSource source = new ByteArrayDataSource(is, mimeType);
mimeBodyAttachments.setDataHandler(new DataHandler(source));
mimeBodyAttachments.setFileName(fileName);
mimeBodyAttachments.setHeader("Content-Type", mimeType +"; name="" + fileName +""");
} catch (IOException e) {
throw new MessagingException(e.getMessage());
}
}
mimeBodyAttachments.setHeader("Content-Transfer-Encoding","base64");
mimeBodyAttachments.setDisposition(MimeBodyPart.ATTACHMENT);
mp.addBodyPart(mimeBodyAttachments);
}

mimeMessage.setContent(mp);

return mimeMessage;
}

1
2
3
4
5
6
7
8

Message createMessageWithEmail(MimeMessage mimeMessage) throws MessagingException, IOException {
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
mimeMessage.writeTo(bytes);
String encodedEmail = Base64.encodeBase64URLSafeString(bytes.toByteArray());
Message message = new Message();
message.setRaw(encodedEmail);
return message;
}

后跟：

1
2
3
4
5

MimeMessage mimeMessage = email.toMimeMessage(userId, context);
Message message = createMessageWithEmail(mimeMessage);
Gmail.Users.Messages messages = service.users().messages();
Gmail.Users.Messages.Send send = messages.send(userId, message);
send.execute(); // method hangs when using large attachment