I ran into this few years ago and didn't find correct solution. Correct means nice & clean. Ended with adding 1/2 of line height, which causes another issues like wrong vertical alignment of elements. It was pre NSAttributedString era on iOS. Height was wrong even if returned width <= constrained width.
Did spend on this couple of weeks and finally gave up. On Friday, 17. May 2013 at 19:25, Quincey Morris wrote: > On May 17, 2013, at 06:38 , Koen van der Drift <koenvanderdr...@gmail.com> > wrote: > > > CGSize frameSize = > > CTFramesetterSuggestFrameSizeWithConstraints(framesetter, CFRangeMake(0, > > stringLength), NULL, CGSizeMake(self.bounds.size.width, CGFLOAT_MAX), > > &fitRange); > > self.frame = CGRectMake(0, 0, self.frame.size.width, frameSize.height); // > > <<<<==== frameSize.height is too small > > > > > I ran into this problem a while back, and after a lot of anguish I think I > worked out what was going wrong. From an admittedly imperfect memory… > > 'CTFramesetterSuggestFrameSizeWithConstraints' sometimes returns a width > that's *larger* than the width in the 'constraints' parameter -- wider than > the view width in your case. So, with your existing code, when the string is > eventually typeset and displayed, your view isn't wide enough for the text to > line-wrap with exactly the same line breaks as it when you got the suggested > frame size, and the text wraps with (generally) one extra line. > > The extra width in the returned value comes from "hanging spaces" -- spaces > at the end of a line that don't count in the line's wrap width. For example, > if you specify a constraint width of 350 points, and the width metric for a > space is 5 points (in the font size being used), then the longest possible > typeset line is actually 355 points. There may also be other typesetting > situations, such as hanging punctuation, which produce similar results. > > This is correct behavior, because the non-space characters in the line are > allowed to use all 350 points of the width. (Hanging punctuation may > partially occupy some of the 350-point width, and partially extend past the > end of the width.) > > Note that the larger width isn't *always* returned -- it depends how close > the non-hanging characters of the longest line come to the constraint width > -- so the problem appears to be intermittent. > > It's disputable, I guess, but I convinced myself it's correct to return a > width >350, because the character that "oversets" the line may have a > non-blank glyph -- even a space, when displaying text with a "show > invisibles" option -- and so needs to be given a place to display. > > Therefore, you need to use the *returned* width for your CTFrame, instead of > your view width. This will mean that the CTFrame may overhang the view on the > right. In most cases this won't matter, since in most cases the overhanging > glyph will be a blank space. > > Alternatively, you can pass a smaller width to > 'CTFramesetterSuggestFrameSizeWithConstraints' -- for example: > self.frame.size.width - (width of a space) -- to ensure that hanging > characters have a place to display. But this is an awkward solution if you > have a mix of fonts and point sizes in your attributed string. > > > _______________________________________________ > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > Please do not post admin requests or moderator comments to the list. > Contact the moderators at cocoa-dev-admins(at)lists.apple.com > > Help/Unsubscribe/Update your Subscription: > https://lists.apple.com/mailman/options/cocoa-dev/robert%40tapmates.com > > This email sent to rob...@tapmates.com _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
