Creating custom TVML Elements using TVInterfaceFactory - https://medium.com/shopgate-mobile-commerce/hacking-tvml-4387e65a9b94#.r4svllt56

AppDelegate.m

/*
 Put that Line of code somewhere before you initialize the javascript application
 You can read a Blogpost about that topic here:
 https://medium.com/shopgate-mobile-commerce/hacking-tvml-4387e65a9b94#.o2onhfgo4
*/

[TVInterfaceFactory sharedInterfaceFactory].extendedInterfaceCreator = [CustomInterfaceCreator new];

application.js

App.onLaunch = function(options) {
  navigationDocument.pushDocument(createDocument("Hello World"));
}
 
var createDocument = function(title) {
  var alertString = `<?xml version="1.0" encoding="UTF-8" ?>
    <document>
      <alertTemplate>
        <sg-attributedText style="width: 1740; height: 100; background-color: rgb(0,0,0); color:white; text-align:center; sg-font:Menlo; font-size: 40; sg-strike-through: true;">${title}</sg-attributedText>
      </alertTemplate>
    </document>`
    var parser = new DOMParser();
    var alertDoc = parser.parseFromString(alertString, "application/xml");
    return alertDoc
}

CustomIntefaceCreator.m

/*
CustomInterfaceCreator.m
*/

- (id)init
{
    self = [super init];
    if (self) {
        //We need to register the element, otherwise there will be an error that the element is not known
        [TVElementFactory registerViewElementClass:[TVTextElement class] forElementName:@"sg-attributedText"];
        
        //Register custom Style Element, otherwise it will not be handed through
        [TVStyleFactory registerStyle:@"sg-strike-through" withType:TVViewElementStyleTypeString inherited:NO];
        
        //Use prefixes for custom elements and styles to prevent overlapping with potentially added elements in the future
    }
    return self;
}

- (UIView *)viewForElement:(TVViewElement *)element existingView:(UIView *)existingView
{
    
    if ([element.elementName isEqualToString:@"sg-attributedText"] && [element isKindOfClass:[TVTextElement class]]) {
        
        TVViewElementStyle * style = element.style;
    
        NSString *fontName = [style valueForStyleProperty:@"sg-font"];
        NSNumber *strikeThroughText = [style valueForStyleProperty:@"sg-strike-through"];
        
        NSRange stringRange = NSMakeRange(0, element.attributedText.length);
        
        NSMutableAttributedString * text = [[NSMutableAttributedString alloc] initWithAttributedString:element.attributedText];
        
        if (strikeThroughText.boolValue) { [text addAttribute:NSStrikethroughStyleAttributeName value:@1 range:stringRange]; }
        
        CGFloat fontSize = element.style.fontSize?element.style.fontSize:11;
        
        UIFont * font = [UIFont fontWithName:fontName size:fontSize];
        if (!font) { font = [UIFont systemFontOfSize:fontSize]; }
        [text addAttribute:NSFontAttributeName value:font range:stringRange];
        
        UILabel * attributedLabel = existingView?(UILabel *)existingView:[[UILabel alloc] initWithFrame:CGRectMake(0, 0, element.style.width, element.style.height)];
        attributedLabel.attributedText = text;
        
        if(style.backgroundColor.color) { attributedLabel.backgroundColor = style.backgroundColor.color; }
        
        /*
         Some more customization to make when needed
         */
        
        return attributedLabel;
        
    }
    
    return nil; //Returning nil means that nothing is done to the element
}

CustomInterfaceCreator.h

@interface CustomInterfaceCreator : NSObject <TVInterfaceCreating>

@end