cs193p – Assignment #3 Extra Task #4

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

Add yet another tab for some “settings” in the game (match bonuses, etc.).

Create new model handling the game settings (like we did already for game results). Its public interface consists of our game settings:

@property (nonatomic) int matchBonus;
@property (nonatomic) int mismatchPenalty;
@property (nonatomic) int flipCost;

The getters for those properties access a helper method which accesses the user defaults and if no valid setting is there returns a default value:

- (int)intValueForKey:(NSString *)key withDefault:(int)defaultValue
{
    NSDictionary *settings = [[NSUserDefaults standardUserDefaults] 
        dictionaryForKey:GAME_SETTINGS_KEY];
    if (!settings) return defaultValue;
    if (![[settings allKeys] containsObject:key]) return defaultValue;
    return [settings[key] intValue];
}

- (int)matchBonus
{
    return [self intValueForKey:MATCHBONUS_KEY withDefault:4];
}

- (int)mismatchPenalty
{
    return [self intValueForKey:MISMATCHPENALTY_KEY withDefault:2];
}

- (int)flipCost
{
    return [self intValueForKey:FLIPCOST_KEY withDefault:1];
}

The setters of the settings properties use another helper method to save their values to the user defaults. (In addition the helper method creates a new property list (dictionary) if it has not been initialized, yet):

- (void)setIntValue:(int)value forKey:(NSString *)key
{
    NSMutableDictionary *settings = [[[NSUserDefaults standardUserDefaults] 
        dictionaryForKey:GAME_SETTINGS_KEY] mutableCopy];
    if (!settings) {
        settings = [[NSMutableDictionary alloc] init];
    }
    settings[key] = @(value);
    [[NSUserDefaults standardUserDefaults] setObject:settings
                                              forKey:GAME_SETTINGS_KEY];
    [[NSUserDefaults standardUserDefaults] synchronize];
}

- (void)setMatchBonus:(int)matchBonus
{
    [self setIntValue:matchBonus forKey:MATCHBONUS_KEY];
}

- (void)setMismatchPenalty:(int)mismatchPenalty
{
    [self setIntValue:mismatchPenalty forKey:MISMATCHPENALTY_KEY];
}

- (void)setFlipCost:(int)flipCost
{
    [self setIntValue:flipCost forKey:FLIPCOST_KEY];
}

Also note, to code above uses constants heavily 😉

#define GAME_SETTINGS_KEY @"Game_Settings_Key"
#define MATCHBONUS_KEY @"MatchBonus_Key"
#define MISMATCHPENALTY_KEY @"MismatchPenalty_Key"
#define FLIPCOST_KEY @"FlipCost_Key"
#define NUMBERPLAYINGCARDS_KEY @"NumberPlayingCards_Key"

Though the card-matching-game model uses those game settings, to be consistent with the MVC scheme, it should not access another model directly. Add properties to its public interface:

@property (nonatomic) int matchBonus;
@property (nonatomic) int mismatchPenalty;
@property (nonatomic) int flipCost;

… and use them instead of the currently used constants.

- (void)chooseCardAtIndex:(NSUInteger)index
{
                ...
                    self.lastScore = matchScore * self.matchBonus;
                ...
                    self.lastScore = - self.mismatchPenalty;
            ....
            self.score += self.lastScore - self.flipCost;
    ...
}

In addition you could set default values when initializing the game:

- (instancetype)initWithCardCount:(NSUInteger)count
                        usingDeck:(Deck *)deck
{
            ...
            _matchBonus = MATCH_BONUS;
            _mismatchPenalty = MISMATCH_PENALTY;
            _flipCost = COST_TO_CHOOSE;
    ...
}

The generic game view controller will now use the settings model and store it in a property, initialized lazily:

#import "GameSettings.h"
...
@property (strong, nonatomic) GameSettings *gameSettings;
...
- (GameSettings *)gameSettings
{
    if (!_gameSettings) _gameSettings = [[GameSettings alloc] init];
    return _gameSettings;
}

… and then pass the settings to the game when it is initialized:

- (CardMatchingGame *)game
{
        ...
        _game.matchBonus = self.gameSettings.matchBonus;
        _game.mismatchPenalty = self.gameSettings.mismatchPenalty;
        _game.flipCost = self.gameSettings.flipCost;
    ...
}

… and also when the view will appear on screen (this way the settings from the settings tab are used immediately when returning to the card game):

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    self.game.matchBonus = self.gameSettings.matchBonus;
    self.game.mismatchPenalty = self.gameSettings.mismatchPenalty;
    self.game.flipCost = self.gameSettings.flipCost;
}

Add a new view controller to the storyboard, link it to the tab-bar controller, name it and choose an icon you setup in your image assets. Add three sliders for the three settings, three labels for their name and another three labels for the value chosen by the sliders:

Create a new view-controller class and connect it to the new view controller in the story board.

Create outlets for the value labels and the sliders:

@property (weak, nonatomic) IBOutlet UILabel *matchBonusLabel;
@property (weak, nonatomic) IBOutlet UILabel *mismatchPenaltyLabel;
@property (weak, nonatomic) IBOutlet UILabel *flipCostLabel;
@property (weak, nonatomic) IBOutlet UISlider *matchBonusSlider;
@property (weak, nonatomic) IBOutlet UISlider *mismatchPenaltySlider;
@property (weak, nonatomic) IBOutlet UISlider *flipCostSlider;

… and another property to hold the settings model, and initialize it lazily:

import "GameSettings.h"
...
@property (strong, nonatomic) GameSettings *gameSettings;
...
- (GameSettings *)gameSettings
{
    if (!_gameSettings) _gameSettings = [[GameSettings alloc] init];
    return _gameSettings;
}

Add three actions for the sliders which set the labels as well as the settings model (using a helper method which also takes care that only discrete values are selectable):

- (void)setLabel:(UILabel *)label forSlider:(UISlider *)slider
{
    int sliderValue;
    sliderValue = lroundf(slider.value);
    [slider setValue:sliderValue animated:NO];    
    label.text = [NSString stringWithFormat:@"%d", sliderValue];
}

- (IBAction)matchBonusSliderChanged:(UISlider *)sender {
    [self setLabel:self.matchBonusLabel forSlider:sender];
    self.gameSettings.matchBonus = floor(sender.value);
}

- (IBAction)mismatchPenaltySliderChanged:(UISlider *)sender {
    [self setLabel:self.mismatchPenaltyLabel forSlider:sender];
    self.gameSettings.mismatchPenalty = floor(sender.value);
}

- (IBAction)flipCostSliderChanged:(UISlider *)sender {
    [self setLabel:self.flipCostLabel forSlider:sender];
    self.gameSettings.flipCost = floor(sender.value);
}

When the tab is selected, set the labels and sliders according to the stored settings:

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    self.matchBonusSlider.value = self.gameSettings.matchBonus;
    self.mismatchPenaltySlider.value = self.gameSettings.mismatchPenalty;
    self.flipCostSlider.value = self.gameSettings.flipCost;
    [self setLabel:self.matchBonusLabel forSlider:self.matchBonusSlider];
    [self setLabel:self.mismatchPenaltyLabel forSlider:self.mismatchPenaltySlider];
    [self setLabel:self.flipCostLabel forSlider:self.flipCostSlider];
}

Finally, create new launch images and adjust them in your image settings.

The complete code is available on github.