Dynamic height of UIWebView with auto layout

Question

I have a problem with setting the height of an UIWebView dynamically. The webview loads a product description which contains html. I want the UIWebView to change its height based on the contents of the description. The parent scrollview should also change its height, but then based on the height of the UIWebView.

Can anyone explain to me how I can achieve the desired behavior of my views?

This is my view hierarchy:

Solution 1

You have to add some code in the delegate method of UIWebView named webViewDidFinishLoad. Here is what you can do:

- (void)webViewDidFinishLoad:(UIWebView *)webView
{
      CGRect frame = webView.frame;
      frame.size.height = 1;
      webView.frame = frame;
      CGSize fittingSize = [webView sizeThatFits:CGSizeZero];
      frame.size = fittingSize;
      webView.frame = frame;

      NSLog(@"size: %f, %f", fittingSize.width, fittingSize.height);

      yourScrollView.contentSize = webView.bounds.size; 
}

The same thing can also be achieved using javascript to find the right height which is as follow:

- (void)webViewDidFinishLoad:(UIWebView *)webView
{
    CGRect oldBounds = [[self webView] bounds];
    CGFloat height = [[webView stringByEvaluatingJavaScriptFromString:@"document.height"] floatValue];
    NSLog(@"NEW HEIGHT %f", height);
    [webView setBounds:CGRectMake(oldBounds.origin.x, oldBounds.origin.y, oldBounds.size.width, height)];
    yourScrollView.contentSize = webView.bounds.size;
}

Hope it helps!

Solution 2

I actually had the same problem recently and ended up figuring it out and putting together a sample project on github.

Comments

[ruhu]

I have a constant height constraint on the webview, how and where can I change the height? Is is in the webviewdidfinishload method?

[tng]

For the record, I have searched high and low for this, and your project was the best help in getting all the auto layout constraints sorted out.

[Julian F. Weinert]

But extremely inaccurate. I get content cut off

[Rajesh73]

To get accurate result, Use observer for contentSize to webView.scrollView