Find UIWebview's content height before loading it - uiwebview

Question

I have a couple of custom cells and web views inside each of these cells. Now,my requirement is to find the height of the HTML string to be loaded on the webview, then based on this change the Custom cell height and the webview height.
I am aware that the document's height can be found in the -webViewDidFinishLoading delegate, but in my app i have a lot of cells and webviews inside each of these cells, so i feel that the app would slow up while scrolling and making unnecessary callbacks
At present i am doing this which gives me the string height.
-(float)getDynemicHeight:(NSString *)pstrText
{
CGSize constraint = CGSizeMake(683,600);
CGSize size = [pstrText sizeWithFont:[UIFont systemFontOfSize:18] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];
CGFloat height = MAX(size.height, 44.0f);
if (height>400) {
return 400;
}
return height;
}
This however causes a problem as even <div> elements are considered as string and hence a larger value of height is returned

Answer 1

In iOS 6, if you just want to show styled text (not text with images mixed in or something like that), you might like to use NSAttributedString instead of a web view. It allows you to create text with different styles in different stretches of text, paragraph margins, etc. etc. Its metrics are well defined and it comes with measurement methods. Simple UIView subclasses such as UILabel can now display an attributed string. Or you can just draw it yourself, directly into the interface.
http://www.apeth.com/iOSBook/ch23.html#_attributed_strings
If you can't do that, then what you're trying to do is basically impossible. You don't know how the Web view will draw a piece of complex HTML until it has drawn the complex piece of HTML. You will simply have to change your app's architecture. For example you could draw all the Web views way ahead of time so you have the needed info during table-dataSource time.