Question

In my iPhone app testing environment, I am reading in .png images from a folder called ChineseCharTest under the Resources folder of my project. I noticed that if I changed the contents of this folder to run a new test with different images, the old images were not being removed from the application memory. I’m trying to remove them each time the test is run so the images being read in are the most recent. Here is the code I am currently using:

NSError *err;
NSFileManager *fileManager = [NSFileManager defaultManager];
NSString* resources_path = [[[NSBundle mainBundle] resourcePath] stringByAppendingString:@"/ChineseCharTest"];
NSArray *prev_test_contents = [fileManager contentsOfDirectoryAtPath:resources_path error:nil];  
NSEnumerator *e = [prev_test_contents objectEnumerator];
NSString *png_filename;
NSString *extension = @"png";
// Remove previous files with .png extension from ChineseCharTest folder
while ((png_filename = [e nextObject])) {
    if ([[png_filename pathExtension] isEqualToString:extension]) {
        BOOL success = [fileManager removeItemAtPath:[resources_path stringByAppendingPathComponent:png_filename] error:&err];
        if (!success) { 
            NSLog(@"Error removing file: %@", [err localizedDescription]);
        }
    }
}

The images from the previous run of the app are not being deleted. The error return on each attempt is the seemingly common Cocoa error 513: The operation couldn’t be completed. Does anyone know what I am doing wrong or another way of doing this?

Much thanks.

Answer 1

Files in your app’s bundle are read-only and any attempt to delete or modify them from iOS will fail.

If you are actually talking about rebuilding your app with different image resources and you are finding that the old ones are still in the app bundle on your test device then you will need to clean your project, delete the app from your test device then re-install it.