EmailMultipleAttachments.kt

val attachmentUris = ArrayList<Uri>().apply {
    add(FileProvider.getUriForFile(activity, "gg.mark.provider", File.createTempFile("gg", ".txt", context.cacheDir)))
    add(FileProvider.getUriForFile(activity, "gg.mark.provider", File.createTempFile("hello", ".txt", context.cacheDir)))
}

val sendEmailIntent = Intent(Intent.ACTION_SEND_MULTIPLE).apply {
    addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)

    type = "text/plain"

    // Needed to get file attachments working on older versions of Android
    if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.LOLLIPOP) {
        addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION or Intent.FLAG_GRANT_READ_URI_PERMISSION)
    }

    putExtra(Intent.EXTRA_EMAIL, EMAIL_RECIPIENTS)
    putExtra(Intent.EXTRA_SUBJECT, "With love from mark.gg")
    putExtra(Intent.EXTRA_TEXT, "Be the change you want to see in the world.")
    putParcelableArrayListExtra(Intent.EXTRA_STREAM, attachmentUris)
}

activity.startActivity(sendEmailIntent)