private String contentType = "PLAIN";
private Class<? extends Screen> dialogClass;
private List<Integer> columnNumbers = new ArrayList<>();

@StudioPropertiesItem(name = "ctype", type = PropertyType.ENUMERATION, description = "Email content type", (1)
        defaultValue = "PLAIN", options = {"PLAIN", "HTML"}
)
public void setContentType(String contentType) {
    this.contentType = contentType;
}

@StudioPropertiesItem(type = PropertyType.SCREEN_CLASS_NAME, required = true) (2)
public void setDialogClass(Class<? extends Screen> dialogClass) {
    this.dialogClass = dialogClass;
}

@StudioPropertiesItem(type = PropertyType.STRING) (3)
public void setColumnNumbers(List<Integer> columnNumbers) {
    this.columnNumbers = columnNumbers;
}

@StudioAction(category = "List Actions", description = "Sends selected entity by email") (1)
@ActionType("sendByEmail") (2)
public class SendByEmailAction<E extends Entity> extends ItemTrackingAction { (3)

    private final MetadataTools metadataTools;
    private final EmailService emailService;

    private String recipientAddress = "admin@example.com";

    private Function<E, String> bodyGenerator;
    private Function<E, List<EmailAttachment>> attachmentProvider;

    public SendByEmailAction(String id) {
        super(id);
        setCaption("Send by email");
        emailService = AppBeans.get(EmailService.NAME);
        metadataTools = AppBeans.get(MetadataTools.NAME);
    }

    @StudioPropertiesItem(required = true, defaultValue = "admin@example.com") (4)
    public void setRecipientAddress(String recipientAddress) {
        this.recipientAddress = recipientAddress;
    }

    public Subscription addEmailSentListener(Consumer<EmailSentEvent> listener) { (5)
        return getEventHub().subscribe(EmailSentEvent.class, listener);
    }

    public void setBodyGenerator(Function<E, String> bodyGenerator) { (6)
        this.bodyGenerator = bodyGenerator;
    }

    public void setAttachmentProvider(Function<E, List<EmailAttachment>> attachmentProvider) { (7)
        this.attachmentProvider = attachmentProvider;
    }

    @Override
    public void actionPerform(Component component) {
        if (recipientAddress == null || bodyGenerator == null) {
            throw new IllegalStateException("Required parameters are not set");
        }

        E selected = (E) getTarget().getSingleSelected();
        if (selected == null) {
            return;
        }

        String caption = "Entity " + metadataTools.getInstanceName(selected) + " info";
        String body = bodyGenerator.apply(selected); (8)
        List<EmailAttachment> attachments = attachmentProvider != null ? attachmentProvider.apply(selected) (9)
                : new ArrayList<>();

        EmailInfo info = EmailInfoBuilder.create()
                .setAddresses(recipientAddress)
                .setCaption(caption)
                .setBody(body)
                .setBodyContentType(EmailInfo.TEXT_CONTENT_TYPE)
                .setAttachments(attachments.toArray(new EmailAttachment[0]))
                .build();

        emailService.sendEmailAsync(info); (10)

        EmailSentEvent event = new EmailSentEvent(this, info);
        eventHub.publish(EmailSentEvent.class, event); (11)
    }

    public static class EmailSentEvent extends EventObject { (12)
        private final EmailInfo emailInfo;

        public EmailSentEvent(SendByEmailAction origin, EmailInfo emailInfo) {
            super(origin);
            this.emailInfo = emailInfo;
        }

        public EmailInfo getEmailInfo() {
            return emailInfo;
        }
    }
}

<action id="sendByEmail" type="sendByEmail">
    <properties>
        <property name="recipientAddress" value="peter@example.com"/>
    </properties>
</action>

@UiController("sales_Customer.browse")
@UiDescriptor("customer-browse.xml")
@LookupComponent("customersTable")
@LoadDataBeforeShow
public class CustomerBrowse extends StandardLookup<Customer> {

    @Inject
    private Notifications notifications;

    @Named("customersTable.sendByEmail")
    private SendByEmailAction<Customer> customersTableSendByEmail; (1)

    @Subscribe("customersTable.sendByEmail")
    public void onCustomersTableSendByEmailEmailSent(SendByEmailAction.EmailSentEvent event) { (2)
        notifications.create(Notifications.NotificationType.HUMANIZED)
                .withCaption("Email sent")
                .show();
    }

    @Install(to = "customersTable.sendByEmail", subject = "bodyGenerator")
    private String customersTableSendByEmailBodyGenerator(Customer customer) { (3)
        return "Hello, " + customer.getName();
    }

    @Install(to = "customersTable.sendByEmail", subject = "attachmentProvider")
    private List<EmailAttachment> customersTableSendByEmailAttachmentProvider(Customer customer) { (4)
        return Collections.emptyList();
    }
}