Padding Bottom Questions

[tcorbet]

01.  I have a test case with three ContainerControllers.  They have the same width, but slightly variant lengths.

02.  I am using the Alice Chapter 1 as the test input.

03.  All four padding properties are set to 10. in a TextLayoutFormat object.

04.  The padding properties appear to be properly applied in all but one single case -- the last visible line in the final container is not properly padded.

04.  Assigning the TLF object to the format property of the TextFlow which is being composed -- as contrasted with assigning to the format properties of each of the three ContainerControllers seems to have some differential effect [attempted because I see that this particular 'style property' does not not have the usual inheritance], but, at the end of the day, no combination seems to guarantee that the final, visible line in the last of the linked containers will be properly formatted.

05. I have searched the forrum and bug bases to the best of my ability, but cannot find anything helpful. The ASDocs entry does have some comments about unique behavior in the case of multi-column formatting with scrolling. I have only a single column per container and no scrolling.

[tcorbet]

01. The example program, MultipleContainerColumns, replicates the same, failed behavior.

02.  Finding no answers, I configured one additional container with ZERO height and set it as invisible.  That does solve the problem, but seems absurd.

03. In searching for answers, I noted in the well-documented, code from QueenCodeMonkey the setting of ContainterController.verticalScrollPolicy to OFF, with a helpful comment that it would prvent partial lines from being laid out in the container.  Her solution also works.

04.  I guess that makes my original question, answered; but it leads to the question:  Where might some newcomer have learned that from reading any of the documentation provided for the Text Layout Framework?

[Jin-Huang]

Are you using TLF 3.0? I cannot reproduce your problem with TLF 3.0. Please attach your code scrap if you still encounter it after switching to TLF 3.0.

Where might some newcomer have learned that from reading any of the documentation provided for the Text Layout Framework?

We have ASDoc, Blog and Forum for TLF developers. And the souce code and builds are in SourceForge.net http://sourceforge.net/projects/tlf.adobe/.

ASDoc is in AS3 API online document along with all the other AS packages.

Blog is located in http://blogs.adobe.com/tlf/.

[tcorbet]

01.  Yes, I am using the latest code, including the update of 11-23 which made the correction to the Pagination example.

02.  You can see the problem without even needing my code.  Run the sample program, MultipleContainerColumns.  When the screen is initially formatted according to the default aize of the Stage, the text will appear just fine.  Then, resize the screen/Stage and you will see that the flow gets reformatted correctly in the first container, but not the second one.  In the second container, the Padding Bottom = 4 declaration will not be honored -- it will be possible for the user to see a partially-visible line.

03.  Yes, I am aware of each of the sources of information you listed; I have spent hours combing through each of them.  The question is, in which of them, is there a clear description of the fact that it is necessary to set VerticalScrollPolicy to OFF in order to avoid that unexepected, and unwanted behavior?

The feedback that I am trying to provide is that what may be well-understood by the designers and developers of the TLF, is probably not nearly so well-understood by someone trying to use the package.  It is a remarkable package, especially in the light of Adobe's pronouncement that it is inevitable that HTML5 will eventually be able to replace the functionality of the Flash Player.  I would be willing to take a bet at 5-1 odds that no browser-agnostic implementation of HTML5/CSS3 will be able to replace the functionality of TLF in the next five years!

But, if the documentation does not inform the development community of how to work with what is, to say the least, a rather unusual partitioning of an M-V-C model, as exemplified in your Pagination demonstration, TLF will not likely ever gain the acceptance you desire and deserve.  I don't think it would be a stretch, in fact, to say that this incorrect handling of PaddingBottom for the last container in the container set is a bug.  It should not be necessary to set Vertical Scroll, or any other scroll property, when the user is not, in fact, configuring TLF to perform any sort of scrolling whatever.

I would encourage you to step back and look at the set of classes, methods and properties, on their own, and more especially in how they are designed to 'connect' with the classes, methods and properties of the spark components and see how clear or unclear they are.  Tweets and blogs are interesting social phenomena, but they don't replace the documentation which must bw a part of the quality assurance sign-off of a product.  In fact, if you take a survey of the tweets and blogs concerning TLF, I think you will see that they are a symptom of the very problems which I am suggesting exist.

[Jin-Huang]

We filed a bug for your case. Thanks for your report and suggestions.

[tcorbet]

01.  Thank you.

02.  I have now been able to work through the issues concerning the proper way to use the TLF for my use case. I would like to pass along my code if it would be of use to anyone with a similar requirement.  While the Pagination example included in the sample directory can be helpful, it can also be quite confusing.  Moreover, pardon the critique, but I think it implements a rather poor separation of Model from View from Controller.  I do not believe that the PaginationWidget ought to be directly controlling how content is being laid out on the screen -- that's not its job.  Its sole purpose ought to be the breaking up of the TextFlow into a Page worth of content.

Queen Code Monkey,http://queencodemonkey.com/2010/10/04/as-per-your-request-tlf-pagination/, has provided a very nice discussion of and presentation of an alternate Pagination approach which I found very helpful.  It makes, I think, a better separation of Model from View from Controller, but I don't know how useful it would be in practice.  She generates additional pages with scrolling, more of less in the fashion of a PDF document.

My view of pagination is based more on the magazine or newspaper article approach in which there are other layout considerations which result in some fixed set of columns through which the article must flow.  But, rather than asking the user to scroll the screen, the Paginator presents the 'page-sized-chunks' in the pre-allocated layout.

We use it, for example, with blogs. Each blog article has some page layout/appearance appropriate to that topic, and that results in usually 2- or 3-columns of some constant width and possibly variable length through which the content of the article should flow in page chunks.  So, the Paginator just worries about its task of composing the containers, but the look-and-feel of the those containers is outside its concern.

03.  If the code would be useful to anyone, please let me know how I can submit it.