Creating image thumbnails to be loaded into tableview from files in app directory - ios

Question

I need some help for a problem which I can't solve but I think I am close to the solution. Here is it:
In a version of my app, I was able to populate a tableview (in CellforRowAtIndexPath) with images taken from the Assetlibrary using the following 2 lines:
ALAsset someAsset = [theAssets objectAtIndex:indexPath.row];
[cell.imageView setImage:[UIImage imageWithCGImage:[someAsset thumbnail]]];
Now, I am trying to read image files from the directory and stored in an NSMutableArray. I can see the filenames when I NSLog the NSMutableArray. But how do I now cause the files to be converted into images and displayed in my tableview in the same way I did why using the Assetlibrary? I have tried several times, but the app either crashes or it does not show the image thumbnails in the table view. For example, this statement does not display the image but the app does not crash:
UIImage *anImage = [UIImage imageWithContentsOfFile:[self.listTable objectAtIndex:0]];
When I setImage in the next line, it doesn't work. Someone please help!
UPDATED: The contents of self.listable when I NSLog it is something like this: "19-10-25 276-10-12.jpg",
"19-10-37 276-10-12.jpg",
"19-10-54 276-10-12.jpg",
"19-10-65 276-10-12.mov", etc.
When I NSLog my documents directory, it is: /var/mobile/Applications/8CB1368A-AAE2-4815-BD26-A7B7C8536193/Documents.

Answer 1

Apps can only imageWithContentsOfFile for files located within the app's sandbox (e.g. in Documents, the bundle, etc.) If these files are located in your Documents folder, you get the full path via:
NSString *documentsFolder = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *imageFullPath = [documentsFolder stringByAppendingPathComponent:imageFilename];
You can then use that in imageWithContentsOfFile.
Update:
You asked:
my directoryContents is an NSArray; how do I convert it to NSString and then [documentsFolder stringByAppendingPathComponent ...] and store each fullpath in the NSMutableArray?
You might do something like:
NSFileManager *fileManager = [NSFileManager defaultManager];
NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSArray *filenames = [fileManager contentsOfDirectoryAtPath:documentsDirectory error:nil];
NSMutableArray *paths = [[NSMutableArray alloc] initWithCapacity:[filenames count]];
for (NSString *filename in filenames)
{
[paths addObject:[documentsDirectory stringByAppendingPathComponent:filename]];
}
NSLog(#"%s filenames = %#", __FUNCTION__, filenames);
NSLog(#"%s paths = %#", __FUNCTION__, paths);