Setting a UIWebViewDelegate programatically.

Question

I am trying to build a custom control based on a UIWebView and compile it into a library for reuse. Everything was working just fine when I had the code all together in a single test app but I'm having some trouble setting up a the delegate for the view for a library. Of note, the sample app used interface builder and thus the delegate was set via IB.

NewsView.h:

@interface NewsView : UIWebView {
   NSObject<UIWebViewDelegate> *delegate;
}
@property (nonatomic, assign) IBOutlet NSObject<UIWebViewDelegate> *delegate;

In the implementation all of my initialization methods call a common method viewInit

NewsView.m

@implementation NewsView

@synthesize delegate;

- (void)viewInit {

    self.delegate = [[NewsViewDelegate alloc] init];
}

If the user clicks on one of the headlines in the view I need the delegate to intercept clicks and launch Safari.

NewsViewDelegate.h

@interface NewsViewDelegate : NSObject <UIWebViewDelegate> {
}

NewsViewDelegate.m

// Intercept URL events
- (BOOL)webView:(UIWebView *)myWebView shouldStartLoadWithRequest:
    (NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {

    NSLog(@"URL Changed");
    // Check to see if this is a click event
    if (navigationType == UIWebViewNavigationTypeLinkClicked) {
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:[[request URL]            absoluteString]]];
            return NO;
    }

    return YES;
}

Unfortunately shouldStartLoadWithRequest never gets called and so clicks are not being launched externally.

I'm sure I'm just missing something, any help would be greatly appreciated.

Thanks!

Answer 1

You are shadowing the existing delegate property of the webview. Try to simply not include the delegate property in your subclass. It should be inherited.

Answer 2

It's typically a bad idea to subclass UIWebView, and the docs specifically advise against it. I don't know for sure, but my guess is that UIWebView is a class cluster.

To get the effect you want, you might try making your NewsView a plain UIView, then add the UIWebView as a subview. From there you can set the UIWebView delegate to the NewsViewDelegate without worrying about the subclass.

The best method might be to create a NewsViewController class that loads your NewsView and implements the UIWebViewDelegate methods itself and set the NewsView webView delegate to your NewsViewController.