Having Trouble calling HUD layer method from game layer Cocos2d

Question

I can get the HUD layer to appear, but I can't seem to update it. I got it working in Ray's tutorial, but for some reason I can't get it working in my own app. I made a new Cocos2d project just so I can try and isolate the problem and I'm having the same issue... maybe you guys can help. ( I'm getting no errors and tried to fix the indentation as best I could for StackOverflow..)

Problem: I can't update the scoreLabel

Code:

GameHUD.h

#import <Foundation/Foundation.h>
#import "cocos2d.h"

@interface GameHUD : CCLayer {

    CCLabelTTF *scoreLabel;

}

- (void) updateScore:(int)score;

@end

GameHUD.m

#import "GameHUD.h"

@implementation GameHUD

- (id) init {

    if (self = [super init]) {

        scoreLabel = [CCLabelTTF labelWithString:@"00000" dimensions:CGSizeMake(240,100) hAlignment:kCCTextAlignmentRight fontName:@"Arial" fontSize:32.0f];
        scoreLabel.anchorPoint = ccp(0,0);
        scoreLabel.position = ccp(200,0);
        scoreLabel.color = ccc3(255, 200, 100);

        [self addChild:scoreLabel];

    }

    return self;
}

- (void)updateScore:(int)score {
    scoreLabel.string = [NSString stringWithFormat:@"%i",score];
}

@end

HelloWorldLayer.h

#import "cocos2d.h"
#import "GameHUD.h"

@interface HelloWorldLayer : CCLayer
{
    GameHUD *_hud;
}

@property (nonatomic,retain) GameHUD *hud;

+(CCScene *) scene;

@end

HelloWorldLayer.m

#import "HelloWorldLayer.h"
#import "AppDelegate.h"

#pragma mark - HelloWorldLayer

@implementation HelloWorldLayer
@synthesize hud = _hud;

+(CCScene *) scene
{
    CCScene *scene = [CCScene node];

    HelloWorldLayer *layer = [HelloWorldLayer node];
    [scene addChild: layer];

    GameHUD *hud = [GameHUD node];
    [scene addChild:hud];

    layer.hud = hud;
return scene;
}

-(id) init
{
if( (self=[super init]) ) {

    // create and initialize a Label
    CCLabelTTF *label = [CCLabelTTF labelWithString:@"Layer A" fontName:@"Marker Felt" fontSize:64];

    // ask director for the window size
    CGSize size = [[CCDirector sharedDirector] winSize];

    // position the label on the center of the screen
    label.position =  ccp( size.width /2 , size.height/2 );

    // add the label as a child to this Layer
    [self addChild: label];

     // Try to update the scoreLabel in the HUD (NOT WORKING)
     [_hud updateScore:74021];

}
return self;
}

// on "dealloc" you need to release all your retained objects
- (void) dealloc
{
    [super dealloc];
}

Only use the [tag:xcode] tag for questions about the IDE itself. Thanks! — Undo, Apr 22 '13 at 20:44
Alright, figured it out. Can't update the hud from the init method, had to do it afterwards. Calling the update method worked fine from ccTouchBegan. I'm guessing the hud object hadn't been created yet? If so, I'm wondering why I wasn't getting a BAD ACCESS error. Strange. — mike, Apr 22 '13 at 21:57
you will get this error only if access released object. before creation all objects in objective-c have value `nil`, not `NULL` as it is in the c++. the main difference is that you can send any message to `nil` without causing error. — Morion, Apr 23 '13 at 06:16

score 1 · Accepted Answer · answered Apr 23 '13 at 01:28

1

The init is called when you invoke [HelloWorldLayer node] when the HUD is not created yet, ie, _hud is nil. Sending message to a nil object is a void operation and it doesn't crash as it is if calling functions on 'NULL` objects.

answered Apr 23 '13 at 01:28

gberginc

447
2
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Having Trouble calling HUD layer method from game layer Cocos2d

1 Answers1