PDF Accessibility – part 2 of 3 (reading fields)
This blog is the second in a series that explores PDF accessibility. This installment describes how to implement PDFs using Adobe LiveCycle Designer so that form fields are accessible to users of assistive technologies.
In this series:
PDF Accessibility – part 1 of 3 (introduction) – an introduction to accessibility standards and technologies
PDF Accessibility – part 3 of 3 (reading text) – a step-by-step guide on making text accessible
WCAG 2.0 Guidelines
1.1.1 Non-text Content: All non-text content that is presented to the user has a text alternative that serves the equivalent purpose 2.4.6 Headings and Labels: Headings and labels describe topic or purpose 3.2.4 Consistent Identification: Components that have the same functionality within a set of Web pages are identified consistently 3.3.2 Labels or Instructions: Labels or instructions are provided when content requires user input 4.1.2 Name, Role, Value: For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies
These guidelines are all about making it easier for assistive technology users to use form fields.
This is important due to the way that assistive technology users interact with a form. Although, fields are typically represented by un-informative shapes such as a rectangle, unimpaired users can rapidly determind its purpose. They have the benefit of being able to scan a form by eye in any direction that they choose and see fields in context; location, label and surrounding content. Assistive technology users can access the same information, but at a slower pace. Mechanisms are required to enable the user to navigate directly through the fields, ignoring other content, and for alternate text to be read which describes the fields’ purpose without relying on context.
Using the field’s caption for alternate text
Whenever possible you should use the field’s caption for alternate text. Set the ‘Screen Reader Precendence’ property to ‘Caption’ in the accessibility pallet.
When a user tabs into this field, the screen reader JAWS V10 with default configuration reads the following:
Your country of citizenship… edit… type in text
The alternate text is read first to identify the field. This is followed by additional information to help the assistive technology user. In this case, it tells the user what type of field this is and how to use it. Although, this approach is common, the text read is specific to screen reader.
Setting custom text for alternate text
There are occasions when it is not appropriate to use the field’s caption, including:
- The field has no caption
- The caption is too verbose
- The caption is not meaningful out of context
Set the ‘Screen Reader Precendence’ property to ‘Custom Text’ and enter the custom text in the ‘Custom Screen Reader Text’ property in the accessibility pallet.
The field has no caption
It is sometimes necessary to implement a field’s label as a separate text object, for instance to implement multi-line labels:
In this case, it is common to use the text from the label object as custom text.
The caption is too verbose
It is important that the alternate text for a field is concise. Verbose captions that are provided to assist a sighted user may be frustrating for a user of assistive technology.
In this case, it is common to paraphrase the caption text.
The caption is not meaningful out of context
Field captions can depend on context to make sense. A common example is radio button lists. Typically, a separate text object is implemented to ask a question and a radio button is provided for each answer.
For instance, when a user tabs into a yes/no radio button list that uses the caption for alternate text, the screen reader JAWS V10 with default configuration would read the following:
Yes… radio button not checked… one of two
To resolve this, it is common to provide custom text that combines the question with the response for that radio button.
A closer look at how alternate text works
How alternate text is read is dependent on the assistive technology used. You can use the attached AltText-TestForm to test. The two most popular screen readers were used for this article:
- JAWS V10
- Window-Eyes V7.1
Screen Reader Precedence
The ‘Screen Reader Precedence’ property on the accessibility pallet has the following values:
- Custom Text
- Tooltip
- Caption
- Name
- None
The screen reader uses this property to determine what text to read. If no text is found, then the screen reader searches for text in the precendence order, starting from Custom Text.
When ‘None’ is selected Window-Eyes performs a search through the precedence order. JAWS does not search through the precedence order, but tries to find a caption, including looking for a text object that may be the label for this field. As a last resort, both screen readers read nothing for the field description, resulting in:
edit… type in text
Using tooltips
Tooltips are used to provide sighted users assistance with completing fields. The text is displayed in a box when the user hovers the cursor over a field.
Typically, tooltips are too verbose to be used as alternate text. To make important tooltip information accessible, it should also be displayed in the form content.
c9eq4xmrbv
Pre-populating forms with LiveCycle ES
Summary
The recommended pre-population technique is on the server as part of a Livecycle ES process. This provides the best user experience and allows leverage of the full power of LiveCycle ES. This is the default implementation for LiveCycle forms rendered as Form Guides or HTML, as you already have the infrastructure in place for rendering these formats.
A light-weight alternative is available for PDF forms: direct web service calls from Reader/Acrobat that requires little or no server infrastructure.
The most common approach for PDF is to pre-populate user data, for instance name, address and contact details for a known user, in a LiveCycle ES process on the server and then use web services from the client to lookup data from large data sets or perform complex/shared validations.
Pre-populating on the server
Pre-population of data into LiveCycle forms on the server is implemented in a LiveCycle ES process. The three core services to enable this are:
- Forms Data Integration (FDI) – for pre-population of XML data into a PDF. This service is bundled with several LiveCycle solution components including Process Management and Reader Extensions
- Forms ES – for pre-population of XML data into an XDP and conversion to PDF, Form Guide or HTML. This is for use cases that are only supported by XDP, including dynamic importing of form fragments
- Output ES – for pre-population of XML into XDP or PDF and conversion to a read-only or printer-ready format
A typical user experience would be:
- User logs into a web-site or portal
- User clicks on a link to a form
- A server web component (any HTTP technology including servlets, jsp, PHP and ASP.NET) handles the request and calls a LiveCycle process, passing a form ID and the user’s ID (either as a web service or using the LiveCycle APIs)
- The LiveCycle process retrieves the form based on form ID
- The LiveCycle process retrieves user data based on the ID and generates an XML file
- The form is pre-populated using one of the services above
- The pre-populated form is returned to the web component which is displayed to the user
Avoka provides a pre-built web component to simplify this implementation – process invoker.
Pre-populating from the client
PDF forms provide the functionality to lookup data directly from Reader/Acrobat using a web service or database lookup. An explanation of how this is implemented is provided by Adobe livedocs.
Web service pre-population is the prefered approach. The database lookup requires that ODBC data source names (DSN) be set up on each user’s machine that will use the form. This may be useful for testing, but is infeasible for production forms. It is not scalable for internal forms and impractical for externally facing forms.
A typical user experience would be:
- The user navigates to a web-site
- The user clicks on a link to a form
- An empty form is displayed within the browser (inside the Acrobat plug-in)
- The user enters a customer ID and clicks a button
- The Acrobat plug-in directly calls a web service, passing in the customer ID
- The web service returns the user’s data which is displayed within the form
Comparison Matrix
| Pre-populating on the server | Pre-populating from the client | |
|---|---|---|
| User experience | The form is already customised for a known user when it is viewed | The form is not personalised to the known user when it is first viewed. The user has to re-enter identifying information into the form and perform an action, for instance click a button, for the web service to be called |
| Maintenance | Changes to the pre-population service can be made in one central location and does not require changes to or re-distribution of forms | Changes to the pre-population service may require changes to and re-distribution of forms |
| Data sources | Pre-populated data can be retrieved from multiple sources and transformed by the LiveCycle process before being pre-populated into the form | Multiple web services can be used from within or outside the organisation |
| Infrastructure | A server installation of LiveCycle ES is required | A lighweight solution that can be implemented with little or no server infrastructure. Server infrastructure is only required to provide access to the form, if it is not to be distributed offline, for instance by email or on CD-ROM/DVD, and to expose web services from your organisation |
| Development tool | Implemented with LiveCycle Workbench | Implemented with LiveCycle Designer |
| Offline support | The user must be logged in and online to view a new form. They can then save the form to their local machine and work offline | The user can either view the form from a web-site or receive it in an email or on fixed media, for instance cd-rom or memory stick. The user must be online to call the web service |
| Technical limitations | None. LiveCycle ES can handle different form types, data sources and transformation requirements | Web services in anything that is not document literal style or returns multiple responses requires custom codingPassword-protected web services cannot be called from a form
Users behind an NTLM authenticating proxy must use Adobe Reader/Acrobat version 9.0 or higher. Typically, this only affects users on corporate environments |
PDF Accessibility – part 1 of 3 (introduction)
This blog is the first in a series that explores the, often misunderstood, field of accessibility. This installment introduces the basic concepts and sets the context for subsequent blogs which will cover the practical aspects of implementing accessible PDF and Flex solutions.
In this series:
PDF Accessibility – part 2 of 3 (reading fields) – a step-by-step guide on making form fields accessible
PDF Accessibility – part 3 of 3 (reading text) – a step-by-step guide on making text accessible
The bottom line
Despite some misconceptions, PDF and Flex/Flash solutions can be highly accessible.
However, it does not happen automagically. Project commitment is required to attain the desired level of accessibility. It is advocated that ITC professionals spend time to understand accessibility, regulatory compliance, the capabilities of Adobe technologies and apply the appropriate level of consideration in project planning.
It is far more expensive to retro-fit changes, rescue a failed project or limit brand damage caused by building a solution that, for example, is unavailable to an important community of Mac users or is complained about in a public forum by a blind user.
What is accessibility?
Accessibility can be considered the degree to which electronic services and products can be accessed by the largest number of users possible. Although, often focused on disabled people, this is relevent to all people, including those that are on slow broadband, using non mainstream operating systems, using a mobile device or speaking non native languages.
Accessibility is closely related to the concept of usability. Usability can be considered the ease with which a specified group of people can use an electronic service or product.
Why should I care about accessibility?
Technological progress and the meteoric rise of the Internet continues to fuel the trend of delivering services and goods through electronic channels. As the trend progresses, the opportunities and responsibilities of accessibility increase.
The three primary reasons to care about accessibility are:
- It is good for business – increase leads and conversion to sales
- It is good for society – provide access for more people to the benefits of technological advancement
- You have to - legislation has been passed around the world that mandates accessibility requirements
Accessibility and disability
Although, accessibility is often set in the context of totally blind people, there are different categories of disabilities with different accessibility requirements.
Types of disability
The major categories of disability types are:
 |
Visual | Blindness, low vision, color-blindness |
 |
Hearing | Deafness |
 |
Motor | Inability to use a mouse, slow response time, limited fine motor control |
 |
Cognitive | Learning disabilities, distractibility, inability to remember or focus on large amounts of information |
What is Assistive Technology?
Assistive technology refers to any product or software program that has been developed or modified to make it accessible for the disabled. Of the wide range of assistive technologies available, the most relevent to PDF and Flex solutions are screen readers, text-to-speech, screen magnifiers and Braille output devices.
Screen Readers
Screen readers are software that interprets what is being displayed on screen and re-presents it as synthesised speech or on a Braille output device.
According to the WebAIM Survey of Preferences of Screen Readers Users completed in January 2009, the top three screen readers being used by 1121 respondents were:
- JAWS at 74%
- Window-Eyes at 23%
- NVDA at 8%
JAWS and Window-Eyes are commercial products that offer evaluation licences. NVDA is a free, open-source screen reader.
Screen readers are highly configurable, complex software that is designed to enable the operation of a computer in ways that are very different from the traditional keyboard and mouse methods employed by fully sighted users. The WebAIM screen reader simulation tool is an interesting way for a fully sighted user to experience the use of screen readers. It is recommended that screen reader testing be performed by specialist users.
Text to Speech
Text to speech software re-present normal language text as an artificial production of human speech. This software is used by screen readers and can be used independently. Common programs include ReadPlease and NaturalReader.
Screen Magnifiers
Screen magnifiers are software that interface with a computer’s graphical output to present enlarged screen content for the partially sighted.
Braille output devices
Braille output devices re-present text as Braille by raising pins through a flat surface in Braille characters.
What is the web standard for accessibility?
Since 1999 the primary international standard for website accessibility has been the Web Content Accessibility Guidelines (WCAG) developed by the W3C. This has formed the basis for accessibility legislation around the world, including Section 508 in the US and the 2000 Government Online Strategy in Australia.
In December 2008, the W3C released WCAG 2.0 recommendation. Version 2 is a significant update to its predecessor.
WCAG 2.0 is built around four basic principles:
| Perceivable | Information and user interface components must be presentable to users in a way that they can perceive |
| Operable | User interface components and navigation must be operable |
| Understandable | Information and the operation of user interface must be understandable |
| Robust | Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies |
Each of these four principles contains a number of guidelines outlining how a website should meet all users’ needs. Within the guidelines there are a number of success criteria which outline how the web content should be developed to meet the guidelines. There are three levels of conformance within WCAG 2.0, A, AA and AAA (the highest level). In order to conform to WCAG 2.0, the web content must satisfy at least level all of the Level A success criteria.
The diagram below shows the minimum success criteria that must all be satisfied for web content to conform to WCAG 2.0:
WCAG 2.0 introduces the notion of “Accessibility Supported” and the requirement that only “accessibility supported ways of using technologies” can be relied upon to satisfy the success criteria. As both Adobe Reader and Flash Player are free and generally available from the Adobe web site, PDF and Flex satisfy the first of the basic requirements for it to be considered “accessibility supported” under the standard:
- Users of the web must be able to obtain user agents for the Web Content technology that are accessibility supported. The W3C suggests this can be achieved in one of four ways.
- In its basic state the technology is accessible to common user agents – e.g. HTML is supported by browsers. OR
- The technology is supported by an accessible plug in such as Flash that is generally available. OR
- The content is to be used in a closed environment such as a university or corporate network, where the necessary accessibility supported technologies are supplied. OR
- The user agent that allows the technology to be accessible is easy for a person with a disability to obtain and it doesn’t cost any more than it would for someone without a disability.
Developments in the Adobe Acrobat, Reader and Flash Player in partnership with assitive technology vendors results in PDF and Flex passing the second of the basic requirements:
- The way a particular web content technology is used must be supported by the assistive technology, that is, if you use JavaScript or PDF, for example, you must do so in a way that allows the final product to be accessed by assistive devices like screen readers and switches.
The accessibility myth
It is a misconception that PDF and Flex solutions cannot be accessible. There are two primary reasons for this:
Many existing PDF and Flex solutions on the web are not highly accessible
This is either due to projects not investing in accessibility or, particularly in the case of PDF technology that has been around for a long time, and was developed prior to versions of Reader and Flash Player that do support accessibility.
Although HTML supports accessibility, it is possible (even easy) to implement HTML web-sites that are horribly inaccessible. Just because HTML supports accessibility does not mean that all HTML sites are automatically accessible – it takes effort and care to achieve this.
In the same way modern versions of Reader and Flash do support accessibility and it is possible to build PDF and Flash content that is accessible. It is up to PDF and Flash developers to learn about these features and implement them correctly.
A bias of the earlier standard WCAG 1.0 was towards W3C web technologies
WCAG 1.0 has been the W3C endorsed standard for nine years and is the referenced standard for accessibility legislation around the world. WCAG 1.0 is technology dependent; Guideline 11 of the standard has two checkpoints relating to what technologies are accessible:
- Checkpoint 11.1 has priority 2 (should) and says to use W3C technologies
- Checkpoint 11.4 has priority 1 (must) and says that if you cannot create an accessible page, then an alternate accessible page that uses W3C technologies must be provided
One of the key drivers to WCAG 2.0 was to become technology agnostic, thereby opening the standard to non-W3C technologies such as PDF and Flex.
What do the LiveCycle ‘Process Fields’ really do?
Background
In order to integrate a LiveCyc le PDF form into LiveCycle Process Management, you need to embed some special fields into your form.
The LiveCycle documentation does indicate what these fields are for, but doesn’t really explain exactly how they are used and populated.
Process Field Documentation Link
This blog entry explains how it all really works.
The Fields
The Process fields inside Designer look like this:
The scenarios
When integrating with Process Management, the form will be presented inside Workspace. There are a number of scenarios:
- A user is submitting a form within Workspace (either to initiate a process, or as an item in their To Do list)
- The user has taken an initialization form offline
- The user has taken a form from their inbox offline.
Submitting a form within Workspace
In fact, for this basic scenario, you don’t need the process fields at all. All you really need is a Submit button.
However, if you do use the process fields, you get a few extra capabilities, including user choices, and the option to take the form offline.
The field AWS_SUBMIT is a regular button that contains some Javascript code. This code, among other things, checks whether you’re running in an online (within Workspace) or offline mode. If you’re running online, it simply sends a “click” event to the real submit button, FSSUBMIT_ (which is a hidden http submit button).
Apart from the choice fields described below, none of the other fields are necessary – LiveCycle knows exactly who you are, and what you’re doing, because you’re logged into a live session in Workspace. It’s only when you take a form offline that the other fields are necessary.
Giving the user a choice
Sometimes you want to give your users a choice, which will affect the routes that are taken within the LiveCycle process. If you put a bit of text into the AWS_CHOICE text field, such as “Approve,Deny”, the Javascript code will:
- Display the Action dropdown (if there are no choices, it will be hidden)
- Populate the Action dropdown with the values from the AWS_CHOICE field.
It will look something like this:
You can put your own comma-separated text into AWS_CHOICE, but LiveCycle will automatically do a whole bunch of useful things for you.
- When you create a User Assign Task step in your workflow, check the checkbox that says “Populate Form with Routes”. LiveCycle will then look at all the route names coming out of your User step, and populate AWS_CHOICE with the route names.
- When the user submits the form, LiveCycle will interrogate the value of the Action dropdown, and automatically route the process down the selected route.
Note: If you choose not to use this option, you can simply create rules in your routes that interrogate other data within your form to decide which route to follow.
Note: Certain route names are associated with special icons in Workspace. These are “Approve” and “Reject” (or maybe “Deny”, I forget.) You can configure these special icons and their associated routenames from Adminui.
Taking a form offline.
Once you take a form offline, it is “disconnected” from Workspace. You can fill it in, and when you click the Submit button, it will be submitted via email, rather than over the web. The AWS_Submit button has logic to determine whether you’re online or offline, and submit either via the web or via email.
If you’re submitting via email, the form needs to know what email address to submit it to. This email address is automatically populated by LiveCycle into the AWS_MAILTO field when you take the form offline. Like all the other fields, there’s no real magic – you can set the field to an email address manually or in code if you want to, but generally it’s easier and safer to let the LiveCycle server take care of this for you.
Note: In order to allow offline submissions, you need to set up a email box, and configure LiveCycle to monitor this email box. That’s the subject of another blog sometime. Email info-at-avoka.com if you’re having trouble.
When you submit your form data via email, LiveCycle no longer knows anything about you, or why you’re submitting the form. It simply knows that an email arrived in an inbox containing some XML as an attachment. So…
When you take the form offline, LiveCycle injects some data into a few fields:
- When you take an initialization form offline, the LiveCycle server will populate AWS_PROCESSTYPE with the name of the process that should be initiated when you submit the form. When you submit the form via email, LiveCycle will start the named process on your behalf, using the data from the email attachment.
- When you take a form in your inbox offline, the LiveCycle server will populate AWS_TASKID with the id of the task that this relates to. When the submit the form via email, LiveCycle will complete that task on your behalf.
- In both cases, LiveCycle will use the email address of the sender of the email of the email to determine who the “completer” was. Warning: make sure you send from an email associated with your LiveCycle identity – if LiveCycle doesn’t recognize the sender, it will treat the email as spam, and silently discard the incoming email. (I haven’t verified this lately, but it used to work this way.)
- In both cases, the LiveCycle server will populate the AWS_ASSIGNEDID with the internal LiveCycle ID of the user who was originally assigned this form. I have no idea whether this is used for anything, or why it might be useful to either you or LiveCycle.
- Finally, once you submit via email, Reader will set the AWS_STATUS field from ” ” to “Submitted”. Once this field has the “Submitted” value, you will not be able to submit the form again. This simply prevents duplicate submissions being accidentally emailed.
Summary
While there’s quite a bit of logic associated with these fields, both within the form and with the LiveCycle server, you don’t really need to know how it all works. Just drop the fields into your form, and LiveCycle takes care of the rest. It is helpful, however, to know how this works, so that you can tweak the behaviour if necessary.
Populating a drop-down using XML and Dynamic Binding
In one of our previous blogs, we mentioned several techniques for populating a drop-down list with data. In this posting, we’re going to use a technique called “Dynamic Binding”. We’re going to use an XML file to populate the drop-down, as well as for populating a repeating lists of questions.
The form we’re going to develop is a general purpose survey form, where both the list of questions, and the answers allowed, are pre-populated with XML. Since Designer only supports a single XML file, we’re going to store the drop-down values, the questions, and the answers that the end-user selects, all in the same XML file.
The Sample PDF is here: dynamic_survey_with_embedded_data. Try it out before you start the exercise, so you can see what we’ll end up achieving.
Note:
- You can just open this file in Reader to try it out
- You can open it in Designer to see how it works
- The PDF has two attachments, the XML schema and a sample XML file. Click on the paper-clip icon to get at these.
It also contains the sample XML and schema files as embedded attachments.
Step 1: create the schema
Note that “Question” and “ResponseItem” are repeating, with a cardinality of 1..*. “Questions” will be used to populate the list of questions dynamically. “ResponseItems” will be used to populate the drop-down list containing the user’s responses.
Step 2: Create a simple form
You must save it as a Dynamic PDF form, because it’s going to grow based on the data we put into it. Also, because we’re going to grow the number of questions based on the data in the XML file, we need to use a Flowed rather than Positioned layout.
Note that the table has only one row (set to “repeating” on the binding tab), and a DropDown list with no values specified.
Step 3: Add the schema to the form
Add the schema to the form by defining a new data connection. Embedding the schema is optional, but useful if you’re ever going to use this form within a LiveCycle process.
Step 4: Create the XML file
Make sure it conforms to your schema. Here’s a snippet:
Step 5:Turn on Dynamic Binding
This is available from the drop-down menu of the Object palette in Designer.
Step 6: Bind the schema elements to the form objects
Use the Binding sub-tab of the Object palette.
- Bind Row1 to the Question[*] repeating group – this will ensure that for every row of Question data in the XML, we’ll get a new Row1 in the form.
- Bind the Question and Answer fields to the sub-elements of the repeating group. Note that you use relative binding, because the repeating element is already bound to Row1.
Step 7: Dynamic Binding
Bind the drop-down’s values and labels to the elements defined in the schema. Click on the green “Specify Item Values” link, and in the Dynamic properties dialog, enter the repeating element, and the sub-items containing the text (the values displayed) and value (the values stored in the data). This is summarized in the screenshot below:
If you don’t see the green link, revisit Step 5.
Step 8: Preview the form
In Designer, set the “Data File” to point to your sample xml file.
Click on the Preview tab. You should see something like this:
Try changing the data in the sample XML file (for example, adding “No opinion” to the drop-down data, or a new question), and then preview again. You should see the new question and drop-down items appear.
Finally
You can embed the XML data into the form manually using Acrobat or automate it on the server via LiveCycle Forms or Process Management. Using a LiveCycle orchestration, you could of course generate the XML using a database query or some other source.
If you’d like more information on how to do this, please contact info@avoka.com