stringByEvaluatingJavaScriptFromString回调

Question

i have WebView load html. after scale html

-(void)webViewDidFinishLoad:(UIWebView *)webView
{
    [self setupContentScale];
    self.webView.hidden = NO;
    [self setLoadingIndicatorVisible:NO];
}

scale metods

- (void)setupContentScale
{
    CGFloat scaleFactor = self.webView.bounds.size.width / self.webView.scrollView.contentSize.width;
    if (scaleFactor != DEFAULT_WEBVIEW_SCALE_FACTOR) {
        scaleFactor -= 0.2f; // to be sure that page will be scaled to required size
        [self.webView setScalesPageToFit:NO];
        [self.webView stringByEvaluatingJavaScriptFromString:[NSString stringWithFormat:@"document.body.style.zoom = %f;", scaleFactor]];

    }

    [self updateFontSize];
    [self updateLineHeight];
    [self updateContentWidth];


}

but i have Show indicator while html scale or callback metod and

self.webView.hidden = NO;
[self setLoadingIndicatorVisible:NO];

how get callback?

Answer 1

NSString *StrParameter=@"Test Parameter"

NSString *Str= [NSString stringWithFormat:@"var c = '%@',StrParameter];

[myWebView stringByEvaluatingJavaScriptFromString:Str];

NSString *newStringFinal = [myWebView stringByEvaluatingJavaScriptFromString:@"function final(){ return c; } final();"];

 NSLog(@"RESULT STRING: %@",newStringFinal);

//  Here newStringFinal  has Callback value which have current value of Variable 'c' in javascript...