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Quote:

Usually, I steer clear of PDF files, especially on the Nokia N800 and 770 Internet Tablets. Documents are almost always designed for letter-size pages, and I don't read text where I have to scroll sideways as well as up-and-down. This week, however, the N800's PDF Reader was my salvation. The app is better -- faster, more stable -- than I expected but ignores hyperlinking.

When I read text on a Nokia Internet Tablet, I prefer FBReader to the alternatives. Usually I'll be able to convert my text to the FB2 markup (this is simply XML, not a proprietary or binary format), and FBReader lets me pick fonts and sizes by XML element, so I can arrange this to my finicky satisfaction. And I prefer to page through text using the + and - keys on top of the NIT.

I had chapters of the book in html files, but no time for an html-to-fb2 transformation. So I grabbed a pdb I'd made a while back, since that's the prime alternative among the many formats that FBReader will display.

The book is entitled "How to Think Like a Computer Scientist: Learning with Python," written by Allen Downey, Jeffrey Elkner and Chris Meyers. I was skimming through the text when I was stopped by a code example.

Here's a screen capture from the N800:

Well, the code example isn't stylable by FBReader in pdb format, but if you can't see the indents in Python examples, then you're missing something.

I found the book online at ibiblio.org and then used Adobe Acrobat's feature for making a PDF from web pages with one key setting -- making a custom page size 6 inches wide by 3.6 inches tall.

Opening this PDF, I set the page zoom to "fit page width" and got this sort of thing instead:

As you can see, not only are the lines indented, the code is in a different font and keywords in a different color. All that's been lost in the quick-and-dirty pdb.

I experimented with a few different ways to make the PDF. I found my most successful result by downloading each html chapter, modifying the css stylesheet to choose Trebuchet MS as the font and 16 pt as the font size, then making a PDF of the chapter. (When I did the whole book from the website, the font size wasn't consistent throughout the chapters, why, I don't know.)

That experimentation led me to discover one flaw in the PDF reader -- the Open dialog doesn't display enough characters in a file name. Here are two screen shots showing my chapter file tests in the recent files list and in the Open dialog:

To be honest, I figured a 1135-page PDF would be too unwieldy for the reader to manage, so I started out making individual chapter files from my local html copies. Since the links weren't relative, I used the complete online version to make a single PDF of everything, with the Table of Contents and Index linking to different chapters.

To my surprise, the progress through the pages of this huge document was no slower than through the small single-chapter documents.

The links worked fine on my laptop, but not at all in the NIT's PDF Reader. Navigation in such a huge document is really awkward without being able to use the links or bookmarks. Anyone know more about the linking issue with PDFs?

— Roger Sperberg

For those who are interested, the PDF can be downloaded from here

Added later: Translations of this text into Portuguese and German are also available, as is a paper version from Green Tea Press. The first version by Allen Downey was written with Java examples and then a version rewritten by him for C++. The same clear-headed text was then modified to introduce Python and Logo. I like this book and as its title indicates, in order to learn to think like a computer scientist, you will also need to learn to think like a computer and also, hopefully, simply how to think.

Read the full article.

Re: The PDF reader

Well one thing I've complained about before regarding the otherwise decent PDF Reader is the fact that the app does not automatically navigate to the next/previous page. It seems that the only way to "turn" pages is to use the menu, which is asinine. Every other PDF reader I've ever used knows that when I attempt to scroll past the current page's borders, I want to navigate to the next or previous page.

This completely kills its usability. I expect text reader apps to employ easy one handed operation, and the PDF Reader fails miserably in this regard.

Re: The PDF reader

Quote:

Originally Posted by crackhead (Post 38175)

I expect text reader apps to employ easy one handed operation, and the PDF Reader fails miserably in this regard.

One-handed operation is possible, and I'd even go so far as to say it's easy. It's just a bit long-winded.

If you're in full-screen mode and don't want to switch back so as to get access to the on-screen navigation bar, try this: press the menu button. Press the Down button once, to bring you to "Page". Press Right or the centre button (OK). If you're on the first page, press OK again, otherwise press Down and OK.

I make that five presses on three different keys to move one page forward. It's a bit excessive, I admit, but less annoying than having to toggle full screen on and off.

The thing that annoys me about the PDF Reader is the fact that zoom is in increments of 50%. You can have 150% or 200% but not 180% as in the browser. For most of the documents that I've tried to read, 150% means illegibly small text, 200% means horizontal scrolling.

There's something that puzzles me about Roger's article. I expect I'm missing something obvious but, if the book is available in html, why go to the trouble of converting it to another format, particularly PDF? On any platform, I'd rather read html; that's especially true on the Internet Tablet, where the browser is so much better than the PDF reader.

Art

Re: The PDF reader

Yeah I know you can do it that way, I don't consider having to press the "menu" key and scroll around the context menu as a viable "one handed" solution for something as trivial as navigating between pages.

Re: The PDF reader

When there are no scroll bars showing on the screen, pressing the right side of the scroll circle takes you to the next page.

So it's a one-click process in full-screen mode. That's why it's important to get the page size and proportions right when you make the PDF.

Re: The PDF reader

Quote:

Originally Posted by artkavanagh (Post 38192)

There's something that puzzles me about Roger's article. I expect I'm missing something obvious but, if the book is available in html, why go to the trouble of converting it to another format, particularly PDF? On any platform, I'd rather read html; that's especially true on the Internet Tablet, where the browser is so much better than the PDF reader.

Art

A couple reasons:

I prefer to page rather than scroll down
When the PDF page fits the full screen, a single click brings up a full page of new text; with the browser, a single click is just a few lines

Also, I was able to put the entire book into a single file, which has several advantages. At the time I made it, I expected the links to work and I thought having an index with workable links on the Nokia Internet Tablet would be useful for reference.

Re: The PDF reader

Quote:

Originally Posted by RogerS (Post 38207)

When there are no scroll bars showing on the screen, pressing the right side of the scroll circle takes you to the next page.

I just tried this and it works even if there's a vertical scroll bar showing, just so long as there isn't a horizontal one. Whenever I tried this before, there was always a horizontal scroll bar, so I thought it didn't work. Because the only PDFs that I'm likely to be reading are ones that were intended for bigger screens, I don't see any way of avoiding the horizontal scroll bar. But thanks for the information.

Art

Re: The PDF reader

Yes, that is very interesting. I haven't viewed any N800-formatted PDF's either. Still doesn't solve the problem, but maybe I'll start making my own...

Re: The PDF reader

Might I suggest looking into using iText for batch converting PDF files to N800 format? I looked into it and it seems fairly simple. It's in java 1.4 so it should even be possible to run on the N800. Alternatively somebody could set it up as a web service like MaemoTube. I will look into it once I get my N800 - which should be within a week! Woohoo :-)

Check out http://itextdocs.lowagie.com/tutorial/ for limited, but very application oriented docs.

Re: The PDF reader

I'm not sure I understand why you're even bothering to convert HTML to PDF. Just save the HTMLs and view those. That's what I do with everything. I don't have to deal with any of the PDF problems discussed here (formatting, layout, zoom, missing objects, missing scrollbars, non-functional links). I had also ran into the problem of getting wierd memory errors on large/complex PDFs. Not to mention that the HTML takes up less space on the card.

I save HTML from just about everything I can. If it's more than just an individual page I want, then I use wget, or if I'm on the computer then I use one of the dozens of freely available programs for mirroring a site to my card.