我是这么做的。很好很简单。

String emailUrl = "mailto:email@example.com?subject=Subject Text&body=Body Text";
        Intent request = new Intent(Intent.ACTION_VIEW);
        request.setData(Uri.parse(emailUrl));
        startActivity(request);

解决方案很简单:android文档解释了这一点。

(https://developer.android.com/guide/components/intents-common.html邮件)

最重要的是标志:它是ACTION_SENDTO，而不是ACTION_SEND

另一条重要的线是

intent.setData(Uri.parse("mailto:")); ***// only email apps should handle this***

顺便说一下，如果你发送一个空的Extra，末尾的if()将不起作用，应用程序将无法启动电子邮件客户端。

根据Android文档。如果你想确保你的意图只被电子邮件应用程序处理(而不是其他短信或社交应用程序)，那么使用ACTION_SENDTO动作并包括“mailto:”数据方案。例如:

public void composeEmail(String[] addresses, String subject) {
    Intent intent = new Intent(Intent.ACTION_SENDTO);
    intent.setData(Uri.parse("mailto:")); // only email apps should handle this
    intent.putExtra(Intent.EXTRA_EMAIL, addresses);
    intent.putExtra(Intent.EXTRA_SUBJECT, subject);
    if (intent.resolveActivity(getPackageManager()) != null) {
        startActivity(intent);
    }
}

简单，试试这个

 public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    buttonSend = (Button) findViewById(R.id.buttonSend);
    textTo = (EditText) findViewById(R.id.editTextTo);
    textSubject = (EditText) findViewById(R.id.editTextSubject);
    textMessage = (EditText) findViewById(R.id.editTextMessage);

    buttonSend.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

            String to = textTo.getText().toString();
            String subject = textSubject.getText().toString();
            String message = textMessage.getText().toString();

            Intent email = new Intent(Intent.ACTION_SEND);
            email.putExtra(Intent.EXTRA_EMAIL, new String[] { to });
            // email.putExtra(Intent.EXTRA_CC, new String[]{ to});
            // email.putExtra(Intent.EXTRA_BCC, new String[]{to});
            email.putExtra(Intent.EXTRA_SUBJECT, subject);
            email.putExtra(Intent.EXTRA_TEXT, message);

            // need this to prompts email client only
            email.setType("message/rfc822");

            startActivity(Intent.createChooser(email, "Choose an Email client :"));

        }
    });
}

这是在Android上发送电子邮件最简洁的方式。

 val intent = Intent(Intent.ACTION_SENDTO).apply {
    data = Uri.parse("mailto:")
    putExtra(Intent.EXTRA_EMAIL, arrayOf("email@example.com"))
    putExtra(Intent.EXTRA_SUBJECT, "Subject")
    putExtra(Intent.EXTRA_TEXT, "Email body")
}
if (intent.resolveActivity(packageManager) != null) {
    startActivity(intent)
}

您还需要在清单中(在应用程序标记之外)指定处理电子邮件的应用程序的查询(mailto)。

<queries>
    <intent>
        <action android:name="android.intent.action.SENDTO" />
        <data android:scheme="mailto" />
    </intent>
</queries>

如果你需要在电子邮件正文中发送HTML文本，请将“电子邮件正文”替换为你的电子邮件字符串，就像这样(请注意HTML . fromhtml可能已经弃用了，这只是为了告诉你如何做)

Html.fromHtml(
    StringBuilder().append("<b>Hello world</b>").toString()
)

下面是在android设备中打开邮件应用程序并在编写邮件时自动填充To address和Subject的示例工作代码。

protected void sendEmail() {
    Intent intent = new Intent(Intent.ACTION_SENDTO);
    intent.setData(Uri.parse("mailto:feedback@gmail.com"));
    intent.putExtra(Intent.EXTRA_SUBJECT, "Feedback");
    if (intent.resolveActivity(getPackageManager()) != null) {
        startActivity(intent);
    }
}

 Intent emailIntent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(
            "mailto","ebgsoldier@gmail.com", null));
    emailIntent.putExtra(Intent.EXTRA_SUBJECT, "Forgot Password");
    emailIntent.putExtra(Intent.EXTRA_TEXT, "this is a text ");
    startActivity(Intent.createChooser(emailIntent, "Send email..."));