Local function call from UIWebview

Question

Hi i have an uiwebview, I have prepare the htmlstring format of data to load in webview.

I am using this line to load htmlstring in uiwebview.

     [webView loadHTMLString:htmlstring baseURL:[NSURL URLWithString:[NSString stringWithFormat:@"file:/%@//",imagePath]]];

In the html formated string we have an one image button.When i click the image button i want to call one local function in ViewController.m file.

Is it possible ? Please help me .

I am using

<input type=""image"" onclick=""func()"" src=""icon_blog.png"" name=""image"" width=""30"" height=""30"">

  <script language=""javascript""> function func(){alert(""hee"");}

But alert not shown in iphone . Any one help me ? Thanks in advance.......

Answer 1

There is no straightforward way to call objective-c code from within page loaded in UIWebView.

The only way is to intercept loading of dummy-pages in UIWebView's delegate (– webView:shouldStartLoadWithRequest:navigationType:). There you can make decisions based on request.URL.

- (BOOL)webView:(UIWebView*)_webView shouldStartLoadWithRequest:(NSURLRequest*)request navigationType:(UIWebViewNavigationType)navigationType
{
    NSArray *components = [[[request URL] absoluteString] componentsSeparatedByString:@":"];
    if ([components count] > 1 && [[components objectAtIndex:0] isEqualToString:@"objc"]) {
        if ([[components objectAtIndex:1] isEqualToString:@"someFunctionality"]) {
            // Do something
        }
        return NO;
    }
    return YES;
}

You can trigger those requests by clicking a link, submitting a FORM, or from JavaScript by setting the window's location like this: window.location = "objc:someFunctionality";.