UIWebView canGoBack and canGoForward always return NO

Question

I am trying to load data directly into UIWebView:

[webView loadData:data MIMEType:@"text/html" textEncodingName:@"utf-8" 
          baseURL:nil];

The data is some html string contains some external links. I am trying to enable the back and forward buttons base on the UIWebView properties:

self.forwardBtn.enabled = self.webView.canGoForward;
self.backBtn.enabled = self.webView.canGoBack;

However, even after I clicked on different links in the web view after the initial load, the webView.canGoForward and webView.canGoBack are always returning NO.

Any idea about this?

Answer 1

Ok, I think the problem is if I use loadData or loadHTMLString, and then I check the url of the request in the delegate:

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {
    NSLog(@"url=%@", [request URL]);
    return YES;
}

It seems like that url is empty. I think this is why there is no history for goBack when using loadData.

Answer 2

Easy quick solution, drag and drop bar button items to the xib, set image and untick the Enabled box from the Attribute Inspector.

// WebViewController.h
@interface WebViewController : UIViewController <UIWebViewDelegate, UIAlertViewDelegate>

@property (weak, nonatomic) IBOutlet UIWebView *webView;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *goBack;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *goForward;
@property (weak, nonatomic) IBOutlet UIActivityIndicatorView *activityIndicator;

// WebViewController.m

- (void)viewDidLoad
{
    [super viewDidLoad];

    if ([ReachabilityTest networkConnected] == YES)
    {
        [self.webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:self.urlString]]];
    }
    else
    {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"No Internet Connection!" message:@"Please, make sure you have internet connection" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
        [alert show];
    }

}


- (void)webViewDidStartLoad:(UIWebView *)_webView {

    [self.activityIndicator startAnimating];
}


- (void)webViewDidFinishLoad:(UIWebView *)_webView {

    [self.activityIndicator stopAnimating];
    self.goBack.enabled = [self.webView canGoBack];
    self.goForward.enabled = [self.webView canGoForward];
}