webviewios

@implementation ViewController
NSString *fullURL = @"https://www.human-element.com";
NSString *deviceType = @"?d=iphone";
/*NEVER open any url, containing this string, INSIDE the app.
 ONLY open outside the app. iOS cannot accept donations directly
 within the app as it violates Apple's terms*/
NSString *outsideAppFlag = @"mydonationssite-notarealsite.com";
- (void)viewDidLoad {
    //load webview url
    NSString *urlWithDeviceType = [fullURL stringByAppendingString:deviceType];
    NSURL *url = [NSURL URLWithString:urlWithDeviceType];
    NSURLRequest *Request = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0];
    [_mainWebView loadRequest:Request];
    [_mainWebView setDelegate:self];
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}
- (void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error
{
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Connection"
                                                    message: @"Having trouble reaching HE Demo? Please check your internet connection and restart the app."
                                                   delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
    _loadingLabel.hidden = TRUE;
    //should an error message popup for this error?
    BOOL ignoreError = FALSE;
    if (error.domain == NSURLErrorDomain) {
        if (error.code == NSURLErrorCancelled) {
            //ignore this one, interrupted load
            ignoreError = TRUE;
        }
    }
    //for some reason, twitter triggers a url request to about:blank in order to load.
    //This is necessary for twitter to load, but it triggers a webView error... just ignore about:blank errors...
    //NSString *theURLString = [webView.request.URL absoluteString]; this won't work - it just returns the last successful url
    NSString *urlStr = [error.userInfo objectForKey:@"NSErrorFailingURLStringKey"]; //this works
    if([urlStr hasPrefix:@"about:blank"]){
        //ignore about:blank error
        ignoreError = TRUE;
    }
    //if this error shouldn't be ignored
    if(!ignoreError){
        //show the error message
        [alert show];
    }
}
- (void)webViewDidStartLoad:(UIWebView *)webView
{
    _loadingLabel.hidden = FALSE;
}
- (void)webViewDidFinishLoad:(UIWebView *)webView
{
    _loadingLabel.hidden = TRUE;
    //add "newtab:" before each <a> tag href that fits criteria: 1) must have target="_blank", 2) must NOT have onclick attribute
    NSString *JSInjection = @"javascript: var allLinks = document.getElementsByTagName('a'); if (allLinks) {var i;for (i=0; i<allLinks.length; i++) {var link = allLinks[i];var oncli = link.getAttribute('onclick');if(oncli==undefined||oncli.length<1){var target = link.getAttribute('target'); if (target && target == '_blank') {link.setAttribute('target','_self');link.href = 'newtab:'+link.href;}}}}";
    [webView stringByEvaluatingJavaScriptFromString:JSInjection];
}
- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request
 navigationType:(UIWebViewNavigationType)navigationType
{
    BOOL isExternal = FALSE;
    BOOL isAllow = TRUE;
    NSString *urlStr = request.URL.absoluteString;
    //if the url begins with 'newtab:'
    if([urlStr hasPrefix:@"newtab:"]){
        isExternal = TRUE;
        //while newtab: is at the start of the URL
        while([urlStr hasPrefix:@"newtab:"]){
            //remove the 'newtab:' from the start of the url
            urlStr = [urlStr substringFromIndex:7];
        }
    }else{
        //url does NOT begin with 'newtab:'...
        //if the url request doesn't start with anchor tag
        if (![urlStr hasPrefix:@"#"]){
            //if the url request doesn't start with the webview url
            if(![urlStr hasPrefix:fullURL]){
                //if the link is not a phone number
                if(![urlStr hasPrefix:@"tel:"]){
                    //if the link is not a mailto link
                    if(![urlStr hasPrefix:@"mailto:"]){
                        //then this link should be opened in a separate view
                        isExternal = TRUE;
                    }
                }
            }
        }
    }
    //if this is an external url
    if(isExternal){
        //if this link isn't blank
        if(![urlStr hasPrefix:@"about:blank"]){
            //load the external page
            [self loadExternalView:urlStr];
            isAllow = FALSE; //ignore the url request (let the other "sharedApplication" handle it, instead, outside of the webview)
        }
    }
    return isAllow;
}
//private function to load the external view
- (void)loadExternalView:(NSString *)externalUrl{
    //if the URL does NOT contain the cachnet donations url string
    if ([externalUrl rangeOfString:outsideAppFlag].location == NSNotFound) {
        //if(![externalUrl containsString:outsideAppFlag]){
        //get the alternate ExternalView that holds the external webview
        UIStoryboard* mainStoryboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
        ExternalView *ev = [mainStoryboard instantiateViewControllerWithIdentifier:@"ExternalView"];
        //set the external url that needs to load
        ev.loadUrl = externalUrl;
        ev.outsideAppFlag = outsideAppFlag;
        // Create the navigation controller and present it without unloading the current home view
        UINavigationController *navCtl = [[UINavigationController alloc]initWithRootViewController:ev];
        [self presentViewController:navCtl animated:YES completion: nil];
    }else{
        //if the URL DOES contain the cachnet donations url string...
        //open the url in a SEPARATE browser outside of the app's webview
        NSURL *url = [NSURL URLWithString:externalUrl];
        [[UIApplication sharedApplication] openURL:url];
    }
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
@end