Resize UIWebView to its content
In a UITextView i can resize the height of the control to it's content like this:
CGRect frame = textView.frame;
frame.size.height = textView.contentSize.height;
textView.frame = frame;
But i want to use an UIWebView instead in order to show rich text. The UIWebVie's content is:
NSString *myDescriptionHTML = [NSString stringWithFormat:@"<html> \n"
"<head> \n"
"<style type=\"text/css\"> \n"
"body {font-family: \"%@\"; font-size: %@; }\n"
"</style> \n"
"</head> \n"
"<body>%@</body> \n"
"</html>", @"helvetica",
[NSNumber numberWithInt:12开发者_开发知识库], @"yadayadayada..."];
[webView loadHTMLString:myDescriptionHTML baseURL:nil];
So the UIWebView contains nothing but plain text. How can i achieve result similar to the above UITextView code?
Although in theory the JavaScript method provided
- (void)webViewDidFinishLoad:(UIWebView *)webview
CGRect oldBounds = [[self webview] bounds];
CGFloat height = [[webview stringByEvaluatingJavaScriptFromString:@"document.height"] floatValue];
[webview setBounds:CGRectMake(oldBounds.x, oldBounds.y, oldBounds.width, height)];
}
should work (and seems to work for most people), it just didn't for me. I tried with a number of variation and it always returned a size that has nothing to do with the true content's height. A one liner would come up with 260 or 244 height, for instance. Don't know why (would love to know).
SO i ended up doing as hinted in this answer:
- (void)webViewDidFinishLoad:(UIWebView *)aWebView {
CGRect frame = aWebView.frame;
frame.size.height = 1;
aWebView.frame = frame;
CGSize fittingSize = [aWebView sizeThatFits:CGSizeZero];
frame.size = fittingSize;
aWebView.frame = frame;
NSLog(@"size: %f, %f", fittingSize.width, fittingSize.height);
}
I think the JS way more elegant but hell, it doesn't works for me and can't figure out why, while this method worked out of the box.
Similar to what Micheal suggested, you should be able to get the height of the content by making a call to javascript in the webview's webViewDidFinishLoad callback
ex (untested):
- (void)webViewDidFinishLoad:(UIWebView *)webview
CGRect oldBounds = [[self webview] bounds];
CGFloat height = [[webview stringByEvaluatingJavaScriptFromString:@"document.height"] floatValue];
[webview setBounds:CGRectMake(oldBounds.x, oldBounds.y, oldBounds.width, height)];
}
This is based on a method used in Appcelerator Titanium to resize its webviews based on height if the user sets height to "auto" https://github.com/appcelerator/titanium_mobile/blob/master/iphone/Classes/TiUIWebView.m#L616
I know this is old but I could not find any more recent answers to my problem. I ended up with this sollution. This is valid when using constraints.
- (void)webViewDidFinishLoad:(UIWebView *)aWebView {
// get content size
CGSize fittingSize = [aWebView sizeThatFits:CGSizeZero];
// ajust the height constraint of the webview to the content size
[self.webviewHeightConstraint setConstant:fittingSize.height];
}
There is no simple answer to this, as a UIWebView is a complex scroll view. A few things you could try, all must be done after the UIWebView delegate gets notified that the webpage finished loading (using webViewDidFinishLoad:). Once the delegate knows that UIWebView is loaded, I would try this:
- Try the same contentSize trick, unlikely that it will work, but it might if the page is loaded
Get the height using javascript, like this:
CGFloat windowHeight = [[webView stringByEvaluatingJavaScriptFromString:@"return document.body.scrollHeight;"] floatValue];
Then do your magic with the height as you would with any other view.
Is this what you are looking for ?? UIScrollView *scroll= [[webView subviews]objectAtIndex:0]; CGFloat flo= scroll.contentSize.height;
Maybe shorten the code?
_webView.frame = CGRectMake(_webView.frame.origin.x, _webView.frame.origin.y, _webView.frame.size.width, 1);
CGSize fittingSize = [_webView sizeThatFits:CGSizeZero];
_webView.frame = CGRectMake(_webView.frame.origin.x, _webView.frame.origin.y, _webView.frame.size.width, fittingSize.height);
加载中,请稍侯......
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