There's new stuff for this on iOS 7.
To get the "fitted" size used by the text view after it's updated its text, call usedRectForTextContainer:
on the textView's layoutManager
property, passing the textView's textContainer
property as an argument.
Word of warning about scrolling: Be advised, though, that changing the frame size of a text view after it has updated it's text can have unexpected visual bugs if scrolling is disabled on your text view. If this happens, set scrolling enabled before editing the text of the text view, then disabling it after it's updated (if you need scrolling to remain disabled).
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