gistfile1.m

- (void)achievementUnlocked:(NSString *)achievement {
    [achievements_ addObject:achievement];

    // lazy load the achievements layer
    if (!achievementLayer_) {
        CGSize winSize = [[CCDirector sharedDirector] winSize];
        
        // instantiate the layer
        achievementLayer_ = [[CCLayer alloc] init];
        achievementLayer_.anchorPoint = ccp(0,0);
        achievementLayer_.position = ccp(winSize.width/2, winSize.height - 60);

        // create the achievement badge sprite
        CCSprite *badge = [CCSprite spriteWithSpriteFrameName:@"btn-achievement.png"];
        badge.tag = 1;
        [achievementLayer_ addChild:badge];
        
        // create the achievement label
        CCLabelTTF *label = [CCLabelTTF labelWithString:@"" fontName:@"Chalkduster.ttf" fontSize:18];
		label.color = ccc3(187,54,54);
        label.tag = 2;
		[achievementLayer_ addChild:label];
        
        [self addChild:achievementLayer_];
        [achievementLayer_ release];
    }

    // make the achievement layer really really small
    achievementLayer_.scale = 0.01;
    
    // update the achievement text
    [(CCLabelTTF *)[achievementLayer_ getChildByTag:2] setString:achievement];
    
    achievementLayer_.visible = YES;
    
    // compute the size of the text
    CGSize size = [achievement sizeWithFont:[UIFont fontWithName:@"Chalkduster" size:18]];
    
    // move the achievements badge to the left
    [achievementLayer_ getChildByTag:1].position = ccp(-size.width/2 - 12, 0);
    
    // animate the achievements layer and give it a bouncy feeling
    [achievementLayer_ runAction:[CCSequence actions:
                                 // scale from 0.01 to 1.60
                                 [CCScaleTo actionWithDuration:.2 scale:1.6],
                                 // scale from 1.60 to 0.80
                                 [CCScaleTo actionWithDuration:.1 scale:0.8],
                                 // scale from 0.80 to 1.00
                                 [CCScaleTo actionWithDuration:.1 scale:1],nil]];
}