使用. settype ("message/rfc822")或者选择器会显示所有(许多)支持发送意图的应用程序。

为了让电子邮件应用程序来解决你的意图，你需要指定ACTION_SENDTO作为动作和mailto作为数据。

private void sendEmail(){

    Intent emailIntent = new Intent(Intent.ACTION_SENDTO);
    emailIntent.setData(Uri.parse("mailto:" + "recipient@example.com")); // You can use "mailto:" if you don't know the address beforehand.
    emailIntent.putExtra(Intent.EXTRA_SUBJECT, "My email's subject");
    emailIntent.putExtra(Intent.EXTRA_TEXT, "My email's body");
    
    try {
        startActivity(Intent.createChooser(emailIntent, "Send email using..."));
    } catch (android.content.ActivityNotFoundException ex) {
        Toast.makeText(Activity.this, "No email clients installed.", Toast.LENGTH_SHORT).show();
    }

}

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()
)

这个方法对我有用。它打开Gmail应用程序(如果安装)，并设置邮件。

public void openGmail(Activity activity) {
    Intent emailIntent = new Intent(Intent.ACTION_VIEW);
    emailIntent.setType("text/plain");
    emailIntent.setType("message/rfc822");
    emailIntent.setData(Uri.parse("mailto:"+activity.getString(R.string.mail_to)));
    emailIntent.putExtra(Intent.EXTRA_SUBJECT, activity.getString(R.string.app_name) + " - info ");
    final PackageManager pm = activity.getPackageManager();
    final List<ResolveInfo> matches = pm.queryIntentActivities(emailIntent, 0);
    ResolveInfo best = null;
    for (final ResolveInfo info : matches)
        if (info.activityInfo.packageName.endsWith(".gm") || info.activityInfo.name.toLowerCase().contains("gmail"))
            best = info;
    if (best != null)
        emailIntent.setClassName(best.activityInfo.packageName, best.activityInfo.name);
    activity.startActivity(emailIntent);
}

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);

试试这个:

String mailto = "mailto:bob@example.org" +
    "?cc=" + "alice@example.com" +
    "&subject=" + Uri.encode(subject) +
    "&body=" + Uri.encode(bodyText);

Intent emailIntent = new Intent(Intent.ACTION_SENDTO);
emailIntent.setData(Uri.parse(mailto));

try {
    startActivity(emailIntent);
} catch (ActivityNotFoundException e) {
    //TODO: Handle case where no email app is available
}

上面的代码将打开用户最喜欢的电子邮件客户端预填充的电子邮件准备发送。

源