Home > Articles > Mobile Application Development & Programming

Mastering XPages: Beyond the View Basics

This chapter focuses on the fine art of presenting view data in XPages.
This chapter is from the book

Because the preceding chapter concentrated exclusively on the gory details of data retrieval from Domino views, it's only fitting that this chapter focuses on the fine art of presenting view data in XPages. Once again, a modified version of the Discussion template is used as the sample application. In fact, for this chapter, you need two samples, namely Chapter9.nsf and Chapter9a.nsf. You need to download these resources now from the following website and load them up in Domino Designer so that you can work through all the examples provided: www.ibmpressbooks.com/title/9780132486316.

You will see how this standard template uses the View and Repeat controls to best effect when displaying view data, and extra XPages have been added to show off some new tips and tricks. You will also learn how to extend and modify the behaviors of the view controls using JavaScript, Cascading Style Sheets (CSS), and so on. If you work through all the examples as you read along, you will have consummate expertise on this topic by the end of this chapter!

XPages provides three standard controls for presenting Domino view data, namely the View, Repeat control and Data Table. You will find all three on the Container Controls section of the palette in Designer. You have already done some work with these controls, mostly with the View control, although you have only used the basic properties up until now. You will see here how to put some of the lesser known properties to good use to solve some more advanced use cases. Perhaps it is best to start, however, with an explanation of why there are three different view presentation controls in the first place!

Pick a View Control, Any View Control

When it comes to presenting view data, we all have our individual preferences! For some use cases, a view with a strictly tabular format where rows and columns crisscross to form a rigidly ordered grid layout is what's required. In other scenarios, a more free-form view layout of summary information that allows end users to dynamically dive deeper into the underlying data is the order of the day. In terms of providing off-the-shelf controls to meet these demands, no one-size-fits-all solution exists. In other words, separate specialized renderers are required to handle what are wildly different layout requirements, and each renderer has its own unique set of properties and behaviors that cater to those particular use cases.

Rather than simply describing various alternative view layouts, it is useful for you to see real-world use cases firsthand. As usual, the sample application can be readily called upon to demonstrate different view presentation examples. For example, explore the All Documents view on the main page of the application, and then compare its look and feel to one of the other views in the main navigator, such as By Tag, By Author, By Most Recent, and so on. Some key differences should come to your attention immediately. Chief among these is the interesting capability of the All Documents view to dynamically expand and collapse row content inline. That is, as you hover over any particular row, you are presented with More and Hide links, depending on the current state of the row content. If the row is collapsed, clicking the More option effectively injects an extra row of detail into your view, showing an abstract of the underlying document and presenting options to compose a reply or to switch to a view of documents that contain the same tags. Figure 9.1 summarizes this feature.

Figure 9.1

Figure 9.1 Sample Discussion application using repeat control to render all documents view

The other views do not have this capability and instead display content on a strict one-document-per-row basis. The data in these views is typically organized according to a specific criterion, say by category, author, or date, and feature the standard document link navigators for some of the columns in each row. You will no doubt recognize these behaviors as built-in properties of the View control, and you have already implemented a view sample similar to these in Chapter 3, "Building Your First XPages Application." That first sample demonstrated that you could build simple views using a View control in a matter of minutes. Although it also is possible to build sophisticated view renderings with the View control (as you'll soon see), there are some things it is simply not designed to do—dynamic inline row insertion/deletion being a case in point.

The fancy dynamics shown in Figure 9.1 are achieved using a Repeat control. This container control iterates or "repeats" over every row in the view data source to which it is bound. Any control that is added to the Repeat container (by default it is empty) can be bound to a column in the backend view. The iterative read cycle that occurs at runtime then ensures that all contained controls display the appropriate column value once for every row in the view. Thus, you have a totally free-form means of laying out view data, where nothing is predefined but anything is possible. The presentation content is totally dependent on the controls you choose to add to the Repeat container. It is not required to be structured within an HTML table for example—something you are stuck with when using the View control or Data Table controls whether you like it or not. Also, Repeat controls can be nested within each other, meaning that different data sources can be navigated as part of one overall view presentation.

All this, of course, means the Repeat control is an incredibly powerful and flexible tool for displaying view data—that's the upside! The downside is that you must define all the content and layout data yourself; in other words, it can be a lot of work depending on what you want to achieve. The View control, on the other hand, is somewhere toward the other end of the scale—a View control can be built quickly using easy point-and-click operations, but the end result is more restrictive than is the case with a Repeat control. Again, depending on what you want to achieve, the View control may be the correct instrument to use—a simple case of choosing the right tool for the right job!

To see how the various view controls have been employed in the Discussion template, you can search the Discussion template for the tags xp:viewPanel, xp:repeat and xp:dataTable (in Designer, type Ctrl-H and specify the literal tags in the File Search tab, as shown in the previous chapter). The View control is used in all the aforementioned XPages (By Tag, By Author, By Most Recent) and in AuthorProfileView.xsp. If a user has registered a profile in the application, the Author Profile custom control is one of three views displayed when the user's name is picked from the author cloud. The Repeat control is used for the All Documents page, the presentation of both the tag and author clouds (as shown in Figure 9.1), and to build the response document chain displayed when editing a document that is contained in a hierarchy.

Interestingly, although perhaps not surprisingly, the search for xp:dataTable results in no hits—at least this is true in the out-of-the-box template; however, you can find matches in Chapter9.nsf because a Data Table example has been added for your convenience. The absence of the xp:dataTable tag from the Discussion template and from most other real-world application (at least in this author's experience) is because it offers neither the convenience of a View control nor the flexibility of a Repeat control. In essence, it is like a limited version of both controls and, thus, tends to be left out in the cold when it comes to more sophisticated application development scenarios. It is, however, useful for prototyping and for simple use cases, and we examine a sample Data Table later in this chapter. First, however, it's time to take a closer look at the intricacies of the View control.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020