SlideShow on Cocos2d-iphone

SlideShowLayer.h.m

/* 
 *  SlideShowLayer by Will Larson and Luke Hatcher. 10/29/2008.
 *  Released under MIT License.
 *  Please check out from repository for full license detail.
 *
 *  Nothing too exiting happening here.
 *  Apologies that it is not in Obj2.0
 *  syntax, but I'm still ambivalent about
 *  the ambiguousness of properties. 
 */

#import <UIKit/UIKit.h>
#import "CocosNode.h"
#import "Layer.h"
#import "Label.h"
#import "Sprite.h"

@interface SlideShowLayer : Layer {
    int slidePosition;
    int backgroundXPosition;
    int backgroundYPosition;
    int descriptionXPosition;
    int descriptionYPosition;
    int descriptionHeight;
    int descriptionWidth;
    int fontSize;
    NSString * fontName;
    NSMutableArray * backgrounds;
    NSMutableArray * descriptions;
    Sprite * background;
    CocosNode * description;
}

/*
 *  This is the only method for adding slides to the slide show.
 */
-(void)addSlideWithBackground: (NSString *)imageString
               andDescription: (NSString *)descString;
/*
 *  Methods for advancing, retreating, and starting the slideshow.
 *  There currently isn't a UI mechanism for retreating to already
 *  seen slides, but you could rig something up if you tried hard 
 *  enough. ;)
 */
-(void)displayFirstSlide;
-(void)displayNextSlide;
-(void)displayPreviousSlide;
-(void)displaySlide: (int)slideNumber;
-(BOOL)hasPreviousSlide;
-(BOOL)hasNextSlide;

/*
 *  Mutators and Accessors
 */
-(NSMutableArray *)backgrounds;
-(NSMutableArray *)descriptions;
-(Sprite *)background;
-(void)setBackground: (Sprite *)aSprite;
-(CocosNode *)description;
-(void)setDescription: (CocosNode *)aCocosNode;
-(NSString *)fontName;
-(void)setFontName: (NSString *)aFontName;
-(int)fontSize;
-(void)setFontSize: (int)anInt;
-(int)slidePosition;
-(void)setSlidePosition: (int)anInt;
-(int)backgroundXPosition;
-(void)setBackgroundXPosition: (int)anInt;
-(int)backgroundYPosition;
-(void)setBackgroundYPosition: (int)anInt;
-(int)descriptionXPosition;
-(void)setDescriptionXPosition: (int)anInt;
-(int)descriptionYPosition;
-(void)setDescriptionYPosition: (int)anInt;
-(int)descriptionWidth;
-(void)setDescriptionWidth: (int)anInt;
-(int)descriptionHeight;
-(void)setDescriptionHeight: (int)anInt;
@end

SlideShowLayer.m

/* 
 *  SlideShowLayer by Will Larson and Luke Hatcher. 10/29/2008.
 *  Released under MIT License.
 *  Please check out from repository for full license detail.
 */
#import "SlideShowLayer.h"

@implementation SlideShowLayer

-(id)init {
    self = [super init];
    if (self) {
        /*
         * setting isTouchEnabled is the magic step that
         * allows the layer to be registered for UI events.
         * forgetting this step will lead to great confusion :-/
         */
        isTouchEnabled = YES;
        slidePosition = -1;
        backgrounds = [[NSMutableArray alloc] init];
        descriptions = [[NSMutableArray alloc] init];
        [self setFontName:@"Helvetica"];
        [self setFontSize:24]; 
    }
    return self;
}

- (void) dealloc {
    [backgrounds release];
    backgrounds = nil;
    [descriptions release];
    descriptions = nil;
    [background release];
    background = nil;
    [description release];
    description = nil;
    [fontSize release];
    fontSize = nil;
    [super dealloc];
}

-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    /*
     *  We are using pushScene/popScene instead of replaceScene
     *  (which has superior memory usage characteristics), because
     *  it makes integrating SlideShowLayer much simpler, and helps
     *  avoid binding the code to one application without requiring
     *  us to use the delegate pattern.
     */
    if ([self hasNextSlide]) [self displayNextSlide];        
    else [[Director sharedDirector] popScene];
}

-(void)addSlideWithBackground: (NSString *)imageString
               andDescription: (NSString *)descString {
    [[self backgrounds] addObject:imageString];
    [[self descriptions] addObject:descString];
}

-(void)displayFirstSlide {
    if ([[self backgrounds] count] > 0) {
        [self setSlidePosition:0];
        [self displaySlide:[self slidePosition]];
    }
}

-(void)displayNextSlide {
    if ([self hasNextSlide]) {
        [self setSlidePosition:[self slidePosition]+1];
        [self displaySlide:[self slidePosition]];
    }
}

-(void)displayPreviousSlide {
    if ([self hasPreviousSlide]) {
        [self setSlidePosition:[self slidePosition]-1];
        [self displaySlide:[self slidePosition]];
    }
}

-(void)displaySlide: (int)slideNumber {
    /*
     * Remove existing slide and description.
     */
    if ([self background]) {
        [self remove:[self background]];
    }
    if ([self description]) {
        [self remove:[self description]];
    }
    
    /*
     * Retrieve and generate necessary details for next slide.
     */
    NSString * bgString = [[self backgrounds] objectAtIndex:slideNumber];
    NSString * descString = [[self descriptions] objectAtIndex:slideNumber];
    Sprite * bg = [Sprite spriteWithFile:bgString];
    bg.position = cpv([self backgroundXPosition], [self backgroundYPosition]);
    CocosNode * desc = [Label labelWithString:descString
                                   dimensions:CGSizeMake([self descriptionWidth],
                                                         [self descriptionHeight])
                                    alignment:UITextAlignmentCenter
                                     fontName:[self fontName]
                                     fontSize:[self fontSize]];
    desc.position = cpv([self descriptionXPosition], [self descriptionYPosition]);
    
    // Add the background and desc to the layer.
    [self setBackground:bg];
    [self setDescription:desc];
    [self add:bg];
    [self add:desc];    
}

-(BOOL)hasNextSlide {
    return ([self slidePosition]+1 < [[self backgrounds] count]);
}

-(BOOL)hasPreviousSlide {
    return ([self slidePosition] > 0);
}

-(Sprite *)background {
    return background;
}
-(void)setBackground: (Sprite *)aSprite {
    if (background) [background release];
    background = [aSprite retain];
}

-(CocosNode *)description {
    return description;
}
-(void)setDescription: (CocosNode *)aCocosNode {
    if (description) [description release];
    description = [aCocosNode retain];
}

-(NSMutableArray *)backgrounds {
    return backgrounds;
}

-(NSMutableArray *)descriptions {
    return descriptions;
}

-(NSString *)fontName {
    return fontName
}

-(int)fontSize {
    return fontSize;
}

-(void)setFontSize: (int)anInt {
    fontSize = anInt;
}

-(void)setFontName: (NSString *)aFontName {
    if (fontName) [fontName release];
    fontName = [aFontName retain];
}

-(int)slidePosition {
    return slidePosition;
}

-(void)setSlidePosition: (int)anInt {
    slidePosition = anInt;
}

-(int)backgroundXPosition {
    return backgroundXPosition;
}

-(void)setBackgroundXPosition: (int)anInt {
    backgroundXPosition = anInt;
}

-(int)backgroundYPosition {
    return backgroundYPosition;
}

-(void)setBackgroundYPosition: (int)anInt {
    backgroundYPosition = anInt;
}

-(int)descriptionXPosition {
    return descriptionXPosition;
}
-(void)setDescriptionXPosition: (int)anInt {
    descriptionXPosition = anInt;
}

-(int)descriptionYPosition {
    return descriptionYPosition;
}

-(void)setDescriptionYPosition: (int)anInt {
    descriptionYPosition = anInt;
}

-(int)descriptionWidth {
    return descriptionWidth;
}

-(void)setDescriptionWidth: (int)anInt {
    descriptionWidth = anInt;
}

-(int)descriptionHeight {
     return descriptionHeight;
}

-(void)setDescriptionHeight: (int)anInt {
    descriptionHeight = anInt;
}

@end

UseAge.m

// Initialize scene and slide show layer.
Scene * s = [Scene node];
SlideShowLayer * ssl = [SlideShowLayer node];

// Set positions for the background and labels.
// Generally you'll be using full screen backgrounds
// (screenshots), and positioning them at the center.
[ssl setBackgroundXPosition:100];
[ssl setBackgroundYPosition:100];
[ssl setDescriptionXPosition: 200];
[ssl setDescriptionYPosition: 200];
[ssl setDescriptionWidth:100];
[ssl setDescriptionHeight:300];
[ssl setFontName:@"Helvetica"];      // optional
[ssl setFontSize:24];                // optional

// Add slides in order they appear.
[ssl addSlideWithBackground:@"pic1.png" andDescription:@"Yada yada one."];
[ssl addSlideWithBackground:@"pic2.png" andDescription:@"Yada yada two."];
[ssl addSlideWithBackground:@"pic3.png" andDescription:@"Yada yada 3."];
[ssl addSlideWithBackground:@"pic4.png" andDescription:@"Yada yada 4."];
[ssl addSlideWithBackground:@"pic5.png" andDescription:@"Yada yada 5."];
[ssl addSlideWithBackground:@"pic6.png" andDescription:@"Yada yada six."];

// Start and display the slide show.
[ssl displayFirstSlide];
[scene add:ssl];
[[Director sharedDirector] pushScene:scene];