Data Persistence for images

Question

Hey,
I'm currently doing a little iPhone-App, that allows the user to load images from his library into
UIImageViews. And I would like to save these images, so that after quitting and relaunching the app,
the images are still there.
How can I do this? Can I somehow retrieve the path for the image and save it via archiving?
UIImages don't conform to NSCoding, but I could maybe save the path as a String. But how
do I get the path? Or is there a better way?
Can someone please help me with this?
Thanks a lot!

Answer 1

Hi Shinichi -
Shinichi wrote:
But how do I get the path?
How did you find the image in order to load it into a UIImageView? If this is an image that was pulled up by UIImagePickerController I don't think you can access it directly even if you could obtain a path or key.
UIImages don't conform to NSCoding
Images are intended to be stored in a standard file format. For example use [UIImagePNGRepresentation|http://developer.apple.com/iPhone/library/documentati on/UIKit/Reference/UIKitFunctionReference/Reference/reference.html#//apple_ref/d oc/uid/TP40006894-CH3-SW10] to save a UIImage in a png file.
So for example, if you've copied an image in [imagePickerController:didFinishPickingMediaWithInfo:|http://developer.apple.co m/iphone/library/documentation/UIKit/Reference/UIImagePickerControllerDelegateProtocol/UIImagePickerControllerDelegate/UIImagePickerControllerDelegate.html#// appleref/doc/uid/TP40007069-CH3-SW8], you can certainly save it in a png file, then store the path to that file in a plist (e.g. NSUserDefaults) or database. But I don't think there's any way to save the redundant disk usage by storing a reference to the original (see also: [http://developer.apple.com/iphone/library/qa/qa2009/qa1622.html] and [http://www.iphonedevsdk.com/forum/iphone-sdk-development/17319-how-get-iphone- photo-library-path.html]).
\- Ray