Having trouble saving NSMutable dictionary to documents. UIImage won't save/display - ios

Question

I have a sticker class and I am saving sticker objects to a NSMutableDictionary. Sticker class below:
#import "Sticker.h"
#implementation Sticker
-(instancetype)initWithTitle:(NSString *)title stickerNO:(int)stickerNO image:(UIImage *)image {
self=[super init];
if(self){
self.title=title;
self.stickerNO=[NSNumber numberWithInt:stickerNO];;
self.image=image;
}
return self;
}
//CODING METHODS//////////////
-(void)encodeWithCoder:(NSCoder *)aCoder{
//choose what we save, these are objects
[aCoder encodeObject:self.title forKey:#"title"];
[aCoder encodeObject:self.stickerNO forKey:#"stickerNO"];
[aCoder encodeObject:self.image forKey:#"image"];
}
-(instancetype)initWithCoder:(NSCoder *)aDecoder
{
self=[super init];
if(self){
self.title=[aDecoder decodeObjectForKey:#"title"];
self.stickerNO=[aDecoder decodeObjectForKey:#"stickerNO"];
self.image=[aDecoder decodeObjectForKey:#"image"];
}
return self;
}
#end
The dictionary is managed by the class StickerManager:
#implementation StickerManager
-(instancetype)init {
self = [super init];
//load the dictionary
NSString *path = [self itemArchivePath];
self.stickerDictionary=[NSKeyedUnarchiver unarchiveObjectWithFile:path];
//if there is no dictionary create it and add the default
if(!self.stickerDictionary) {
NSLog(#"Creating dictionary and adding default");
self.stickerDictionary=[[NSMutableDictionary alloc] init];
[self addDefaultStickers];
[self saveStickerDictionary];
}
//if empty fill it
else if ([self.stickerDictionary count]==0){
NSLog(#"Dictionary exists but it empty");
[self addDefaultStickers];
[self saveStickerDictionary];
}
return self;
}
//add the stickers included in the app bundle
-(void)addDefaultStickers {
Sticker *sticker = [[Sticker alloc] initWithTitle:#“Batman” stickerNO:1 image:[UIImage imageNamed:#“batman.png"]];
[self.stickerDictionary setObject:sticker forKey:sticker.title];
}
-(BOOL)saveStickerDictionary{
NSLog(#"Saving stickers");
//get the path from above
NSString *path = [self itemArchivePath];
return [NSKeyedArchiver archiveRootObject:self.stickerDictionary toFile:path];
}
-(NSString *)itemArchivePath
{
//get the directory
NSArray *documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
//set it to a string
NSString *documentDirectory = [documentDirectories firstObject];
//here we call the file items.archive
return [documentDirectory stringByAppendingPathComponent:#"stickers.archive"];
}
#end
If when the StickerManager is init if it is empty or doesn't exist it will create and fill the dictionary with the default stickers by calling addDefaultStickers. This is working for the one sticker I have in the code. I can load and restore the dictionary and use NSLog to check the contents. The sticker is there but for some reason the UIImage is null and I can't display it. I'm really not sure why, I have used the encodeWithCoder for it so shouldn't it work? The odd thing is that if I download a sticker from Parse.com (I have an identical class on it) and then convert that image from NSData to png and save it will work. Could someone give me some pointers please to what might be going wrong here? Thanks
EDIT This is my download from Parse.com code:
- (void)getNewStickersWithCompletionHandler:(stickerCompletionHandler)handler
{
__weak StickerManager *weakSelf = self;
PFQuery *stickersQuery = [PFQuery queryWithClassName:#"sticker"];
[stickersQuery findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
if(!error) {
for( PFObject *object in objects) {
NSString *title = object[#"title"];
int stickerNO = [[object objectForKey:#"stickerNO"] intValue];
//DOWNLOAD IMAGE CODE
PFFile *image = object[#"image"];
[image getDataInBackgroundWithBlock:^(NSData *data, NSError *error) {
if(!error){
UIImage *image = [UIImage imageWithData:data];
Sticker *sticker = [[Sticker alloc] initWithTitle:title stickerNO:stickerNO image:image];
[weakSelf.stickerDictionary setObject:sticker forKey:sticker.title];
[self saveStickerDictionary];
handler(YES,nil);
}
}];//end get image block
}//end for
}
}];//end download stickers block
}
If I save a sticker to the dictionary this way there are no issues and I can display the image. This is almost identical to the addDefaultStickers, I am saving a UIImage and not saving the NSData. No Idea what is up here..

Answer 1

just for other people's reference the problem was in not first converting the UIImage to NSData. I changed UIImage lines in the aCoder method to below:
[aCoder encodeObject:UIImagePNGRepresentation(self.image) forKey:#"image"];
and in the aDecoder: self.image = [UIImage imageWithData:[aDecoder decodeObjectForKey:#"image"]];
don't totally understand why it was working for NSData that was converted to a UIImage for the Parse download before but it's all working now anyway.