Question

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Scoring System In Cocos2D

I got a reply from a question I asked earlier but I am new to coding and have no idea how to do it. Here is the reply:

"@synthesize a "score" property of type int, and a "scoreLabel" property of type CCLabelTTF.

initialize your score property to "0" in -(void)init

On line 126, increment your "score" property by 1, and set that value into your CCLabelTTF."

Can you tell me how to do this? plz. link to my other post

—– Scoring System In Cocos2D

Answer 1

When you synthesize a private variable (other classes cannot see it) you allow a way for other classes to see and/or modify the value of that variable.

First, you want to create the variable:

NSMutableArray *_targets;
NSMutableArray *_projectiles;

int _score;
CCLabelTTF *_scoreLabel;

Then in your init method to set the _score to 0:

-(id) init
{
    if( (self=[super init] )) {
        [self schedule:@selector(update:)];
        _score = 0;

Then increment (add 1 to) your _score variable and set the string (the text content) of your _scoreLabel to that value.

        if (CGRectIntersectsRect(projectileRect, targetRect)) {
            [targetsToDelete addObject:target];     
            _score++;
            [_scoreLabel setString:[NSString stringWithFormat:@"%d", _score]];                    
        }   

The line [_scoreLabel setString:[NSString stringWithFormat:@"%d", _score]]; is a way to convert the integer of _score to a string (NSString). It’s an old C way of doing it, the %d means that whatever is going to be there should be displayed as an integer as opposed to a float (having decimal points).

It also looks like you need to “instantiate” your label and add it as a child to the layer. Instantiation is just a fancy term for creating a instance of something. Think of a “class” as a blueprint for a chair, and an “instance” as a chair created from that blueprint. Once you have the chair created (an instance), you can modify it (paint it, add/remove legs, etc).

So, to instantiate your label and add it to the layer (itself):

-(id) init
{
    if( (self=[super init] )) {
        [self schedule:@selector(update:)];
        _score = 0;

        //Create label
        _scoreLabel = [CCLabelTTF labelWithString:@"0" fontName:@"Marker Felt" fontSize:16];

        //Add it to a layer (itself)
        [self addChild:_scoreLabel];