Cells are sized according to the value returned from heightForRowAtIndexPath:. You could theoretically call sizeToFit: on a cell you create inside that method to get a height, but it would be very expensive to create a cell for every call to this method. One technique you might try is to create a static cell that you use for every call to heightForRowAtIndexPath:. You just dump your new label contents in there for each row and sizeToFit.
Luke On Nov 2, 2012, at 8:07 AM, Matt Neuburg <m...@tidbits.com> wrote: > Okay, I have this wild and crazy idea. I've got a UITableView with cells that > have different heights. The cells' content consists almost entirely of > UILabels, and the height of each cell depends on what's going to go into > those labels - the cell needs to grow to accommodate the text of the labels. > The way I've always done this in the past is to calculate how the labels will > be drawn, using NSString sizeWithFont etc, and then lay out the labels and > calculate the needed cell size. > > But it occurs to me that in theory constraints could do all the work for me. > I'm already using constraints to resize the actual labels when the cell > changes size to assume its final height, but maybe I could use constraints to > *make* cell assume its final height based on the content of the labels. The > cell is in a nib, so if there were just one label, the code might be > something like this: > > NSArray* objs = [[UINib nibWithNibName:@"Cell" bundle:nil] > instantiateWithOwner:nil options:nil]; > Cell* cell = objs[0]; > cell.bounds = CGRectMake(0,0,320,50); > cell.lab.text = // whatever the actual content will be > [cell.lab sizeToFit]; // or something :) > > The idea is that the label will assume its final size and the existing > constraints will push the cell height larger as needed. Okay, but it isn't > working; the cell isn't growing. > > My theory is that this probably *can't* work because the auto layout stuff > doesn't kick in unless the view is actually in the interface, which (as you > can see) it isn't. And probably not until the next run loop, either, which is > not good enough; I need to run through a whole lot cells and do this, right > now, to calculate all the cell heights in advance of the table appearing. > > So, am I right that this is just impossible, or is there some cool way to do > it that I just haven't stumbled on yet? Thx - m. > > -- > matt neuburg, phd = m...@tidbits.com, http://www.apeth.net/matt/ > pantes anthropoi tou eidenai oregontai phusei > Programming iOS 5! http://shop.oreilly.com/product/0636920023562.do > RubyFrontier! http://www.apeth.com/RubyFrontierDocs/default.html > TidBITS, Mac news and reviews since 1990, http://www.tidbits.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/luketheh%40apple.com > > This email sent to luket...@apple.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
