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Not Just Flash, Flex and Dreamweaver!

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Have you seen Mike Potter’s LiveCycle @ MAX Google Calendar ? It’s a great way to see all the LiveCycle -related sessions being offered at the Adobe MAX 2006 conference this year.

I think many people still think or expect that MAX is still all about the former Macromedia products such as Flash, Flex and Dreamweaver. While there’s still lots of focus on those really cool applications, Adobe has added a whole slew of sessions on LiveCycle products such as Designer, Workflow, Forms and even a preview of what we’ve got in store for LiveCycle 8!

Posted by Stefan Cameron on September 11th, 2006
Filed under Conferences,MAX 2006

Bug: "Page n of m" Custom Object Broken in Tables

Description

If you use the “Page n of m” object from the Library palette’s Custom tab, you may have noticed a bug when you drag that object from the Library directly into a table cell:

Canvas.gif

In the image above, the “Page n of m” object circled in green is correct whereas the one circled in red is not.

If you preview the form or run it in stand-alone Acrobat, you’ll get something like this:

Preview.gif

You can see, in the image above, that the green-circled object is showing the correct page information while the red-circled one isn’t showing any information at all. That’s because the text object from red-circled “Page n of m” object contains broken references to the Floating Fields which are used to display the current page and page count information.

Workaround

The “Page n of m” is a special object that’s actually made-up of 3 separate fields:

  • A hidden floating numeric field named “CurrentPage” which displays the current page’s number.
  • A hidden floating numeric field named “PageCount” which displays the total number of pages.
  • A text object which references both the CurrentPage and PageCount fields and has the text “Page # of ##”.

Hierarchy.gif

The image above shows how the red- and green-circled objects in the first image are represented in the Hierarchy palette which clearly shows that each “Page n of m” object is a hybrid object made-up of 3 separate objects.

The “Page n of m” works by using what Designer calls Floating Fields where a field (such as CurrentPage) is referenced by another object’s text. In theory, that would mean that you should be able to place floating fields in captions as well as in text objects however Designer only supports them in text objects.

If you use the XML Source tab to look at the source for the green-circled object, you’ll see how this is done (please note that I’ve abbreviated it here for clarity):

<field name="CurrentPage" presence="hidden" access="readOnly"
      id="floatingField011478"/>
<field name="PageCount" presence="hidden" access="readOnly"
      id="floatingField029358"/>
<draw name="Pages">
  <ui><textEdit/></ui>
  <value>
    <exData>
      <body>
        <p>
          Page <span xfa:embed="#floatingField011478"/> of
          <span xfa:embed="#floatingField029358"/>
        </p>
      </body>
    </exData>
  </value>
</draw>

In the above XML source, you can see that the text object (named “Pages”) has valid references to the CurrentPage and PageCount fields because its “xfa:embed” tags use their pertaining IDs.

If we now look at the XML source for the red-circled (broken) “Page n of m” object, it’s clear that the text object’s references to the CurrentPage and PageCount fields are broken since the IDs used by the Page text object don’t match those assigned to the CurrentPage and PageCount hidden Floating Fields:

<subform>
  <field name="CurrentPage" presence="hidden" access="readOnly"
      id="floatingField025864_copy1_copy1_copy1"/>
  <field name="PageCount" presence="hidden" access="readOnly"
      id="floatingField015020_copy1_copy1_copy1"/>
  <draw name="Pages">
    <ui><textEdit/></ui>
    <value>
      <exData>
        <body>
          <p>
            Page <span xfa:embed="floatingField025864"/> of
            <span xfa:embed="floatingField015020"/>
          </p>
        </body>
      </exData>
    </value>
  </draw>
</subform>

This can be easily fixed by modifying the IDs of the CurrentPage and PageCount fields to be the ones that the Page text object is expecting them to be: floatingField025864 and floatingField015020, respectively. Once you’ve fixed the IDs, previewing the form should give you something like:

FixedPreview.gif

You can see now that the once-broken “Page n of m” object in the table cell is functioning properly.

Fix

Please refer to the Bug List for updated information on the version(s) affected by this bug as well as if and when it was/will be fixed.

Posted by Stefan Cameron on September 6th, 2006
Filed under Bugs,Designer

Making a Table of Contents

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One of the hottest topics on the Designer Forums these days seems to be methods by which one can add a table of contents to their form. Since there are many different ways to achieve this, I thought I would post a little sample to demonstrate how this can be done.

Of primary concern when adding a table of contents to your form is ensuring that the links provided to the form’s various pages/sections remain valid at all times. Static forms whose page set never changes don’t really need to worry about this but dynamic forms do. That is, regardless of whether content pages are added, re-ordered or even deleted from your dynamic form, you need to ensure that when a TOC link is clicked, the user is taken to the correct page pertaining to the topic they selected.

The best way of ensuring that TOC links don’t get broken as a result of changes to the form’s pages is by using layout information provided by the XFA Layout Model. This model provides information such as an object’s actual dimensions (width/height), the page on which it is located as well as a few other interesting pieces of information.

By using the

xfa.layout.absPage

we’re able to get the page number on which an object is currently located, taking into account the various pages which may have been inserted or removed in-between the TOC page and the page in question. Taking that page number and assigning it to the

xfa.host.currentPage

property then sets the current page to the one on which is located the object in quetsion.

Download Sample [pdf]

Minimum Requirements: Designer 7.x, Acrobat 7.x.

page or absPage?

If you’re looking at the Adobe XML Form Object Model Reference (page 188), you’ll notice that there are actually two methods which provide the number of the page on which an object is currently located:

xfa.layout.page // returns a 1-based number

and

xfa.layout.absPage // returns a 0-based number

Since we need to set that information to the

xfa.host.currentPage

property and that it expects a zero-based page number, it’s simpler to use the absPage version.

The Layout:Ready Event

When using the XFA Layout Model, it’s very important to realize that the information it contains is constantly updated whenever something on your form changes that may affect an object’s positional data. Therefore, you must ensure that the form’s layout has been updated before you attempt to obtain information from it about a particular object.

For TOC page fields that display the page number on which a topic is currently located, it’s easier to simply put script in the Layout:Ready event of that field since this event is fired every time the form’s layout process is complete. Therefore, whenever pages get added, re-ordered or even removed, this event is fired and the fields are updated with the most current information.

Alternatively, if you’re writing script in another event and you need to know whether information in the XFA Layout Model is up-to-date, you can use the

xfa.layout.ready

boolean property which returns true if the form’s layout process is complete and false otherwise.

Links in XFA

A lot of customers have asked me how to create links in XFA. The concept of links is essential to a TOC page since it’s sole purpose is to provide links to various pages within a document.

Unfortunately, XFA 2.4 (used by Designer 7.1+ and Acrobat 7.0.5+) doesn’t have the ability to describe the equivalent of an HTML anchor (link) or a PDF Bookmark. Therefore, we’re forced to cheat a little. One way of doing that is by using a transparent button overlaid on top of another object (text or field) which displays information about a link. You could also use a button directly by using its caption to describe what it links to but you’ll most likely run into text alignment problems if you need the button’s caption to be anything but centered.

My sample uses the former solution and places transparent buttons over the fields which display information about the link (title and current page number). You can make a button transparent by removing its caption text and customizing its Appearance property (on the Object palette’s Field tab) to remove its borders and fill.

Finally, the z-order (or top-down order in the Hierarchy palette) of the transparent buttons used as links with respect to the fields over which they’re to be located is very important in that the buttons must be above (higher in z-order or lower in the Hierarchy palette) the fields to which they pertain. One way to do this is by selecting a button and choosing the “Layout | Bring to Front” menu item. This will ensure that when you click on the topic, you’ll click on the link button rather than the field which describes the topic.

Posted by Stefan Cameron on September 4th, 2006
Filed under Scripting,Tutorials

Bug: Cannot Override Calculations

2

Description

The XFA language supports fields which are calculated yet still overridable by the person filling the form. For instance, you may have an invoice on which you calculate the tax associated with a purchase using a calculated field yet, for customers from other countries, you would like to allow them to override the calculated tax amount and enter the correct amount themselves.

To do this, you would use the Object palette’s Value tab and set the field’s Type property to Calculated – User Can Override. You could even go as far as specifying an Override Message which would appear if the user attempted to override the field’s calculated value.

In theory, when the user attempts to override the field’s calculated value, either the Override Message or, if none was specified, an Acrobat default message appears warning that the field is calculated and gives the user the option to continue with the override or to cancel. If the user proceeds with the override, subsequent calculations use the override value instead of the original calculated value regardless of subsequent changes to other fields which the overridden field’s calculations were dependent on.

Unfortunately, there’s a bug in Acrobat that causes the overridden value to be discarded. It manifests itself in a couple of different ways:

  1. Dynamic PDF: Not only will the value specified by the user (the override) not be retained but the Override Message (if specified) won’t be displayed. The behavior is simply to let the user type-in a value but then throw it away and run the calculation again without any warning.
  2. Static PDF: In this case, the Override Message (if specified) is displayed and the user has the option to discard their change or proceed with the override but the specified value is discarded regardless of what they choose to do and the calculation is run again.

Workaround

You could use two fields and a check box where the first field is simply “Calculated – Read Only” and the second field is the override value and is invisible until the check box is checked.

All calculations which depend on the calculated field in question would need to verify the value of the “override” check box: If it’s unchecked, calculations would use the value from the first field which itself may be calculated. If it’s checked, they would use the value from the second field which contains the override value.

Checking the check box would cause the first (calculated) field to become invisible and the second (override) field to become visible. You could even display an Override Message when the check box gets checked and use the

xfa.host.response("Question", "Title", "Default Value")

statement to give the user the option to cancel the override (the return value is null if the user picked the Cancel button).

Fix

Please refer to the Bug List for updated information on the version(s) affected by this bug as well as if and when it was/will be fixed.

Posted by Stefan Cameron on August 29th, 2006
Filed under Acrobat,Bugs

The Bug List Goes Live!

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Some of you may have noticed the new Bug List side bar module on my blog recently. I’m excited to launch this new section of my blog tonight and I hope that it’ll add even more value to your visits here as well as to your experience using Designer and Acrobat to design and develop your electronic forms.

Look for a few kick-off posts in the coming days about some bugs that fellow readers and users have reported as well as some that I’ve come across myself while making the various samples I’ve already posted to this blog. Of course, there shouldn’t be any in the features I worked on… 😉

My hope for this new section is that it’ll serve as a reference for things to watch-out for in the versions of Designer and/or Acrobat that you may be using as well as what to do in order to get around them.

Posted by Stefan Cameron on August 25th, 2006
Filed under Bugs