cs193p – Assignment #4 Extra Task #2

Please note, this blog entry is from a previous course. You might want to check out the current one.

Knowing how to find Sets in the remaining cards also would allow you to let the user cheat. Have a button that will show them a Set (if available). It’s up to you how you want to show it, but maybe some little indicator (a star or something) on each of the 3 cards?

Add a new button to storyboard:

… and link to an action which stores a possible combination in a new property:

- (IBAction)touchCheatButton:(UIButton *)sender {
    self.cheatCards = [self.game findCombination];
    [self updateUI];
}

Define that property as array:

@property (strong, nonatomic) NSArray *cheatCards;

Reset the array, when a new deck is dealt:

- (IBAction)touchDealButton:(UIButton *)sender {
    ...
    self.cheatCards = nil;
    ...
}

When updating a card first remove all image subviews (previously added star images). If the card is one of the current “cheat”, add a small star in the top left corner of the card:

#define CHEATSTARSIZE 0.2
#define CHEETSTAROFFSET 0.1
- (void)updateUI
{
            ...
        } else {
            cardView = self.cardViews[viewIndex];
            if (!card.matched) {
                [self updateView:cardView forCard:card];
                
                for (UIView *subView in cardView.subviews) {
                    if ([subView isKindOfClass:[UIImageView class]]) {
                        [subView removeFromSuperview];
                    }
                }
                if ([self.cheatCards containsObject:card]) {
                    UIImage *image = [UIImage imageNamed:@"star.png"];
                    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
                    CGFloat min = cardView.bounds.size.width;
                    if (cardView.bounds.size.height < min) min = cardView.bounds.size.height;
                    imageView.frame = CGRectMake(min * CHEETSTAROFFSET, min * CHEETSTAROFFSET,
                                                 min * CHEATSTARSIZE, min * CHEATSTARSIZE);
                    [cardView addSubview:imageView];                    
                }
            } else {
                ...
    }

Using an image like above is a quick solution, but might add unwanted aliasing effects. Creating the star “by hand” using bezier curves might produce a nicer looking result. If you go for the image solution, don’t forget to add that image to your image assets.

The complete code is available on github.