NSCoding, save image path instead of actual image - objective-c

Question

#property (strong) UIImage *thumbImage;
..
albumData *album1 = [[albumData alloc]initWithTitle:#"Eminem" style:#"123" thumbImage:[UIImage imageNamed:#"1.jpeg"]];
..
- (void)encodeWithCoder:(NSCoder *)coder {
NSData *image = UIImagePNGRepresentation(_thumbImage);
[coder encodeObject:(image) forKey:#"thumbImageData"];
}
- (id)initWithCoder:(NSCoder *)coder {
NSData *imgData = [coder decodeObjectForKey:#"thumbImageData"];
_thumbImage = [UIImage imageWithData:imgData ];
return self;
}
Right now I'm using the above code to save data inside a plist file. How should I change the code in order to save just the image path \ name instead of saving the actual picture.

Answer 1

If you have the file name, you can get its path using -[NSBundle pathForResource:ofType:], e.g.
[[NSBundle mainBundle] pathForResource:#"1" ofType:#"jpeg"];
As rmaddy said, you cannot get this from a UIImage, so you may have to get it and hang on to it when you create the image.

Answer 2

You should use
#property (copy) NSString *thumbImage;
and save only image name instead of
#property (strong) UIImage *thumbImage;
then code/encode as string. When you need an image just write
[UIImage imageNamed:album1.thumbImage];
Another solution is to subclass UIImage class, add image path property, owerride UIImage's initialization methods to support saving path and override coder/encoder methods
EDIT:
Here is some example code:
UIImageWithPath.h
#import <UIKit/UIKit.h>
#interface UIImageWithPath : UIImage{
NSString* filepath;
}
#property(nonatomic, readonly) NSString* filepath;
-(id)initWithImageFilePath:(NSString*) path;
#end
UIImageWithPath.m
#import "UIImageWithPath.h"
#implementation UIImageWithPath
#synthesize filepath;
-(id)initWithImageFilePath:(NSString*) path{
self = [super initWithContentsOfFile:path];
if(self){
[filepath release];
filepath = [path copy];
}
return self;
}
-(void)dealloc{
[filepath release];
[super dealloc];
}
#end
Sample using:
- (void)viewDidLoad
{
[super viewDidLoad];
img = [[UIImageWithPath alloc] initWithImageFilePath:[[NSBundle mainBundle] pathForResource:#"pause" ofType:#"png"]];
iv.image = img;
}
-(void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];
NSLog(#"image file path %#", img.filepath);
}
So now your code/encode methods should look like this:
-(void)encodeWithCoder:(NSCoder *)coder {
NSString *path = _thumbImage.filepath;
[coder encodeObject:(path) forKey:#"thumbImageData"];
}
- (id)initWithCoder:(NSCoder *)coder {
NSString *path = [coder decodeObjectForKey:#"thumbImageData"];
_thumbImage = [[UIImageWithPath alloc] initWithImageFilePath:path];
return self;
}