这个函数首先直接意图gmail发送电子邮件，如果gmail没有找到，然后提升意图选择器。我在许多商业应用程序中使用了这个功能，它工作得很好。希望对你有所帮助:

public static void sentEmail(Context mContext, String[] addresses, String subject, String body) {

    try {
        Intent sendIntentGmail = new Intent(Intent.ACTION_VIEW);
        sendIntentGmail.setType("plain/text");
        sendIntentGmail.setData(Uri.parse(TextUtils.join(",", addresses)));
        sendIntentGmail.setClassName("com.google.android.gm", "com.google.android.gm.ComposeActivityGmail");
        sendIntentGmail.putExtra(Intent.EXTRA_EMAIL, addresses);
        if (subject != null) sendIntentGmail.putExtra(Intent.EXTRA_SUBJECT, subject);
        if (body != null) sendIntentGmail.putExtra(Intent.EXTRA_TEXT, body);
        mContext.startActivity(sendIntentGmail);
    } catch (Exception e) {
        //When Gmail App is not installed or disable
        Intent sendIntentIfGmailFail = new Intent(Intent.ACTION_SEND);
        sendIntentIfGmailFail.setType("*/*");
        sendIntentIfGmailFail.putExtra(Intent.EXTRA_EMAIL, addresses);
        if (subject != null) sendIntentIfGmailFail.putExtra(Intent.EXTRA_SUBJECT, subject);
        if (body != null) sendIntentIfGmailFail.putExtra(Intent.EXTRA_TEXT, body);
        if (sendIntentIfGmailFail.resolveActivity(mContext.getPackageManager()) != null) {
            mContext.startActivity(sendIntentIfGmailFail);
        }
    }
}

Kotlin版本，只显示电子邮件客户端(没有联系人等):

    with(Intent(Intent.ACTION_SEND)) {
        type = "message/rfc822"
        data = Uri.parse("mailto:")
        putExtra(Intent.EXTRA_EMAIL, arrayOf("user@example.com"))
        putExtra(Intent.EXTRA_SUBJECT,"YOUR SUBJECT")
        putExtra(Intent.EXTRA_TEXT, "YOUR BODY")
        try {
            startActivity(Intent.createChooser(this, "Send Email with"))
        } catch (ex: ActivityNotFoundException) {
            // No email clients found, might show Toast here
        }
    }

这将只显示您的电子邮件客户端(以及PayPal出于某些未知的原因)

 public void composeEmail() {

    Intent intent = new Intent(Intent.ACTION_SENDTO);
    intent.setData(Uri.parse("mailto:"));
    intent.putExtra(Intent.EXTRA_EMAIL, new String[]{"hi@example.com"});
    intent.putExtra(Intent.EXTRA_SUBJECT, "Subject");
    intent.putExtra(Intent.EXTRA_TEXT, "Body");
    try {
        startActivity(Intent.createChooser(intent, "Send mail..."));
    } catch (android.content.ActivityNotFoundException ex) {
        Toast.makeText(MainActivity.this, "There are no email clients installed.", Toast.LENGTH_SHORT).show();
    }
}

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);
    }
}

发送电子邮件可以用intent完成，不需要配置。但这样就需要用户交互，布局也会受到一些限制。

在没有用户交互的情况下构建和发送更复杂的电子邮件需要构建自己的客户端。第一件事是用于电子邮件的Sun Java API不可用。我曾经成功地利用Apache Mime4j库来构建电子邮件。都是基于nilvec的文件。

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);