Re: Tk Characters

I'm very sorry, but to the best of my knowledge, Tk is not really capable of displaying Arabic strings coherently. (Oh I wish it could -- my life would be so much easier! But alas...)

The things Arabic needs that Tk doesn't provide are:

Bidirectionality ("bidi" text). Actually, I don't know of any GUI library or display tool (including the latest/greatest browsers) that does a proper job of handling bidirectional text, because in general, there is no "right way" to do this (that is, no bidi algorithm exists that can do the right thing in all cases). But the popular browsers, and Qt and I think Gtk, can do the right thing most of the time. Tk simply has no ability whatsoever in this regard.
Context-sensitive character shapes and ligatures. The "primary" unicode page for Arabic (U+0600-U+06FF) defines only the "canonical" letters and marks, without being concerned about their various "initial/medial/final" variations in shape -- and virtually all Arabic text data you will ever encounter is written using the characters in this range. There's a whole separate section of unicode for the "contextualized" versions of the letters and marks, and a whole pile of display logic for converting "canonical" strings into strings of these variants, in order to assemble a display that makes sense to competent readers of Arabic. Again, Qt and Gtk have this covered, but so far as I know, none of this logic has been ported to Tk. (I would love it if someone showed me I was wrong about this).

There's an appreciable set of applications that can work fairly well without worrying about bidi text -- they just happen to never mix Arabic words with Latin-based words or digit strings on the same line in a display, and they generally don't encounter things like bracketing characters (parens, etc). But without a working method for context-sensitive character rendering you've got a non-starter.

So, either get up to speed on Qt or Gtk, or else configure your app to use HTML and browsers as the GUI. (update: or, knuckle down and build the parts for Tk that are missing...)

Comment on Re: Tk Characters

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Re^2: Tk Characters by Anonymous Monk on May 12, 2009 at 10:22 UTC
Great , thank you very much .. Today I came across the problem of text direction , I can display Arabic words but it in the reverse order ! As you mentioned maybe it doesn't worth all this headache simply I can use HTML output.. But the thing is why I can't find books about Perl and QT, GTK, and the rest of GUI's ? regards Swalif	[reply]
Re^3: Tk Characters by graff (Chancellor) on May 12, 2009 at 12:38 UTC
Search here at the monastery for stuff about Gtk. Our own zentara has posted a variety of very helpful information about it, including some sample apps. Between that and the online documentation for Gtk, you should have enough to get started (after you get both the Gtk libraries and the CPAN module installed).	[reply]