I know a similar question has been asked before but it seemed never been answered. I have a UIWebView and add some content by string. I use UIWebView because I add some images to it dynamically and also use other HTML features. This example code is simplified.
NSString *myHtmlString = @"SOME LONG TEST STRING 1234567890 123456789 0123456789 0123456789 0123456789 01234567890 WWWWWWWWWW WWWWWWWWWW WWWYYYYYYY YYYYYYYYYY YYYYYYYYYY YYYYYYYYYY YYYYYYYYYY YYYYYYYYY YYYYYYYWWW WWWWWWWWWW WWWWWWWWWW WWWXXXXXXX XXXXXXXXXX XXXZZZZZZZ THIS IS THE END I WANT TO SEE";
NSString *myPath = [[NSBundle mainBundle] bundlePath];
NSURL *myBaseURL = [NSURL fileURLWithPath:myPath];
[myWebVi开发者_Go百科ew loadHTMLString:myHtmlString baseURL:myBaseURL];
What I want to see is the end of the string. I can scroll there, no problem. But I want to go there programatically.
This is fairly simple. First, you'll need to obtain height of the webpage:
NSInteger height = [[webView stringByEvaluatingJavaScriptFromString:@"document.body.offsetHeight;"] intValue];
Now you have the height of the document stored in the height variable. To scroll to bottom you have to use javascript again:
NSString* javascript = [NSString stringWithFormat:@"window.scrollBy(0, %d);", height];
[webView stringByEvaluatingJavaScriptFromString:javascript];
Of course you need to call them in proper moment. That is
– webViewDidFinishLoad:(UIWebView *)webView
method of your webview delegate.
in iOS 5+ you could call the following method from your -(void)webViewDidFinishLoad:(UIWebView *)webView
- (void)webViewScrollToBottom:(UIWebView *)webView
{
CGFloat scrollHeight = webView.scrollView.contentSize.height - webView.bounds.size.height;
if (0.0f > scrollHeight)
scrollHeight = 0.0f;
webView.scrollView.contentOffset = CGPointMake(0.0f, scrollHeight);
}
This is how you can scroll down Animated:
- (void)webViewDidFinishLoad:(UIWebView *)webView
{
CGPoint bottomOffset = CGPointMake(0, self.myWebView.scrollView.contentSize.height - self.myWebView.scrollView.bounds.size.height);
[self.myWebView.scrollView setContentOffset:bottomOffset animated:YES];
}
SWIFT 4.x
This is how you can scroll down Animated:
func webViewDidFinishLoad(_ webView: UIWebView) {
var scrollHeight: CGFloat = webView.scrollView.contentSize.height - webView.bounds.size.height
if (0.0 > scrollHeight) {
scrollHeight = 0.0
}
webView.scrollView.setContentOffset(CGPoint.init(x: 0.0, y: scrollHeight), animated: true)
}
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