Why UIWebView work so slowly when loadHTMLString with UIWebView? - iphone

Question

It take about 10s to loadHTMLString in my APP, who can point out what's the problem?
- (void)viewDidLoad {
[super viewDidLoad];
webView = [[UIWebView alloc]initWithFrame:CGRectMake(10, 10, SCREEN_WIDTH, 480)];
[webView setBackgroundColor:[UIColor clearColor]];
[webView setOpaque:NO];
webView.delegate = self;
[scrollView addSubview:webView];
}
After enter the view, If I receive message:
- (void)updateJournalView:(NSArray *)journals {
NSString *descHtml = [self getHtmlDesc:journals];
[webView loadHTMLString:descHtml baseURL:nil];
}
getHtmlDesc method will return the html string quickly.
from load log, you can see it take about 5s to load.
2012-11-26 20:34:35.322 test[8456:c07] ====start load 2012-11-26 12:34:35 +0000:
2012-11-26 20:34:39.890 test[8456:c07] ====finish load 2012-11-26 12:34:39 +0000:
Following is UIWebViewDelegate method:
- (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;
scrollView.contentSize = CGSizeMake(SCREEN_WIDTH, fittingSize.height);
NSLog(#"====finish load %#:", [NSDate date]);
}
- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request
navigationType:(UIWebViewNavigationType)navigationType {
NSURL *url = [request URL];
if ([[url scheme] isEqualToString:#"redirect"] &&
[[url host] isEqualToString:#"opp_detail"]) {
NSString *oppIdStr = [[url path] stringByReplacingOccurrencesOfString:#"/player_id=" withString:#""];
if (oppIdStr && [oppIdStr length]) {
NSNumber *oppId = [NSNumber numberWithInt:[oppIdStr intValue]];
if ([oppId intValue] != gcontext.me.id) {
[screenNav gotoOppDetailScreen:[oppId intValue]];
}
}
}
return YES;
}
- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request
navigationType:(UIWebViewNavigationType)navigationType {
NSURL *url = [request URL];
if ([[url scheme] isEqualToString:#"redirect"] &&
[[url host] isEqualToString:#"opp_detail"]) {
NSString *oppIdStr = [[url path] stringByReplacingOccurrencesOfString:#"/player_id=" withString:#""];
if (oppIdStr && [oppIdStr length]) {
NSNumber *oppId = [NSNumber numberWithInt:[oppIdStr intValue]];
if ([oppId intValue] != gcontext.me.id) {
[screenNav gotoOppDetailScreen:[oppId intValue]];
}
}
}
return YES;
}
- (void)webViewDidStartLoad:(UIWebView *)webView{
NSLog(#"====start load %#:", [NSDate date]);
}
Please give me a hand, why it is so slow when loadHTMLString with UIWebView?

Answer 1

If there is nothing heavy to render, then it's possible that all about slow disk operations, that are performing when you're reading your html string.
https://stackoverflow.com/a/3400892/1851930