Hi Aki, Many thanks for your reply, much appreciated. I completely stripped all my custom drawing code and everything to double-check it wasn't just some bad expectation of glyph-to-character mapping in my own code, but the problem persists. I've uploaded the sample, stripped down project here:
http://www.literatureandlatte.com/misc/HiddenTextTestBasic.zip All it contains is two text views that share the same text storage, one of which (the left one) uses the custom glyph generator to hide text (given that my real app allows the user to view the same text storage in different panes, it may be that the user has text hidden in one pane but not in the other). To see the bug in action, all you need to do is build the project, then, in the right-hand text view (where the text isn't hidden), click somewhere between the square brackets (i.e. inside the text that has been hidden in the left-hand text view) and hit return to create a new line twice. The second time you hit return, you will get the following exceptions thrown on the console: 2008-03-10 20:15:21.121 HiddenTextTest[2956:813] Exception raised during background layout: *** NSRunStorage, _NSBlockNumberForIndex(): index (170) beyond array bounds (163) 2008-03-10 20:15:21.122 HiddenTextTest[2956:813] *** NSRunStorage, _NSBlockNumberForIndex(): index (170) beyond array bounds (163) 2008-03-10 20:15:23.320 HiddenTextTest[2956:813] *** NSRunStorage, _NSBlockNumberForIndex(): index (170) beyond array bounds (163) 2008-03-10 20:15:23.321 HiddenTextTest[2956:813] *** NSRunStorage, _NSBlockNumberForIndex(): index (170) beyond array bounds (163) After that, you can't type any more - the text view is frozen. You just get more errors along the lines of: 2008-03-10 20:20:16.799 HiddenTextTest[2956:813] Exception raised during background layout: -[NSLayoutManager _fillLayoutHoleForCharacterRange:desiredNumberOfLines:isSoft:] *** attempted layout while textStorage is editing. It is not valid to cause the layoutManager to do layout while the textStorage is editing (ie the textStorage has been sent a beginEditing message without a matching endEditing.) I did find that if I set -setBackgroundLayoutEnabled: to NO, these errors go away, but I suspect that this is really just masking the underlying problem rather than fixing it - and besides, I'd really prefer to have background layout enabled. Many thanks for taking an interest in this. All the best, Keith ----- Original Message ---- From: Aki Inoue <[EMAIL PROTECTED]> To: Keith Blount <[EMAIL PROTECTED]> Cc: cocoa-dev@lists.apple.com Sent: Monday, March 10, 2008 6:14:05 PM Subject: Re: Glyph Generator & hiding glyphs -> _NSBlockNumberForIndex() errors Keith, I was consulted about the sample from DTS and didn't find any obvious problem with it. It would be great if you could provide further detail (for example, bt of the exception raise). Thanks, Aki On 2008/03/08, at 10:41, Keith Blount wrote: > Just to add a little info to my previous message, which was a little > misleading:a > > My custom glyph generator replaces each glyph that is supposed to be > hidden with NSNullGlyph (it doesn't just insert one NSNullGlyph for > the lot of them), so I would expect the one-to-one mapping on this > first pass of glyph generation to be maintained. I'm therefore > really not sure why I'm getting all of these errors - it seems that > the presence of a group of null glyphs completely breaks things at > the typesetting stage (I'm guessing)? Hmm, given that there is so > little documentation about this sort of thing and most glyph > generation threads seem to have been unanswered, I don't hold out > much hope... > > In case there is a better way of doing things: I am basically trying > to implement hidden text, so that text with a given custom attribute > does not get displayed in the text view. One way I could have done > this was via a custom text storage subclass that maintained two > representations of its text - one with the hidden text displayed, > one with it, um, hidden - but this is no good for what I want, as > the same text storage can be displayed in two different text views, > and there is more than one attribute type that can be hidden > separately. > > Hence the custom glyph generator, which isn't working... > > Thanks in advance for any help or pointers. > All the best, > Keith > > > --- ORIGINAL MESSAGE --- > > Hi, > > I have a custom glyph generator (NSGlyphGenerator subclass) that is > used to hide glyphs for text with certain attributes. It does this > by inserting a single NSNullGlyph for a range of glyphs representing > text with these hidden attributes. (This is basically a hidden text > toggle.) This all works brilliantly - I can completely hide whole > ranges of text - but only so long as the text is viewed in a single > text view. > > If I have the same text storage shared between two text views, and > one view has the text hidden whilst the other doesn't, I get array > out of bounds errors under the following circumstances: If, in the > view where no text is hidden, I click in the range of text that IS > hidden in the other view, and then I hit return a couple of times, I > get these errors: > > Exception raised during background layout: *** NSRunStorage, > _NSBlockNumberForIndex(): index (345) beyond array bounds (335) > 2008-03-08 10:28:00.042 HiddenTextTest[42350:813] *** NSRunStorage, > _NSBlockNumberForIndex(): index (345) > > Clearly, these errors are caused because my hidden-text view has > less glyphs in it than the non-hidden-text view, but they both share > the same text storage. So my question is, how do I fix this? > Somewhere it seems that I need to tell something else - other than > my glyph generator - that some text is hidden. The errors seem to > indicate that I might need to tell my text storage about this... But > where and how? But then, I can't tell the text storage, because it > has hidden text in one view but not the other... > > The method of hiding text by inserting a null glyph was recommended > to me by DTS, but there is very little documentation on actually > achieving something like this, so I'm hoping some text expert here > will be able to give me some clues. :) > > Many thanks in advance and all the best, > Keith > > > > > ____________________________________________________________________________________ > Looking for last minute shopping deals? > Find them fast with Yahoo! 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