Create NSMutableArray with all objects in Subfolder

[JuanMazuera]

Hi everybody!

I've been looking for this all over the web but i have not found a good answer i hope someone could help me.

how can I do to start a NSMutableArray with all the objects (images) in a specific subfolder inside the documents folder at the app startup? this folder can contains any number of files...

thanks in advance

[vja]

Originally Posted by JuanMazuera

Hi everybody!

I've been looking for this all over the web but i have not found a good answer i hope someone could help me.

how can I do to start a NSMutableArray with all the objects (images) in a specific subfolder inside the documents folder at the app startup? this folder can contains any number of files...

thanks in advance

hi!

look at NSFileManager methods, for example, result array contains all items in documents directory:

@implementation Utils

+ (NSString *) documentsDirectory {
	static NSString* dPath = nil;
	
	if (!dPath) {
		dPath = [NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex: 0];
		[dPath retain];
	}
	
	return dPath;
}

// ....
NSArray * docsContent = [[NSFileManager defaultManager] contentsOfDirectoryAtPath: [Utils documentsDirectory]											error: nil];

[JuanMazuera]

Originally Posted by vja

hi!

look at NSFileManager methods, for example, result array contains all items in documents directory:

@implementation Utils

+ (NSString *) documentsDirectory {
	static NSString* dPath = nil;
	
	if (!dPath) {
		dPath = [NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex: 0];
		[dPath retain];
	}
	
	return dPath;
}

// ....
NSArray * docsContent = [[NSFileManager defaultManager] contentsOfDirectoryAtPath: [Utils documentsDirectory]											error: nil];

i'll give it a try, i have read that document, it is just i haven't managed it to work, thanks for your answer

[Duncan C]

Originally Posted by JuanMazuera

Hi everybody!

I've been looking for this all over the web but i have not found a good answer i hope someone could help me.

how can I do to start a NSMutableArray with all the objects (images) in a specific subfolder inside the documents folder at the app startup? this folder can contains any number of files...

thanks in advance

You want a mutable array that contains UIImage objects that are loaded from a folder at startup?


Use NSFileManager defaultFileManager to get a pointer to the system's file manager object.

Create a string that cottons a path to your images folder by first getting the path to the documents folder, and then appending the subfolder name to the end.

Use a method like contentsOfDirectoryAtPath:error to get a list of filenames (and folder names) from that subdirectory.

loop through those names, skipping the folder names.

For each filename, use CGImage imageWithContentsOfFile to load that image.

Then add that image to your mutable array and continue.

You'll have to do a certain amount of research to put that code together, but it isn't rocket science. It should be a method about 1/2 page long.

[vja]

in this case be safe with memory, don't upload to array a lot of images

[JuanMazuera]

thanks for your answer... actually of that 1/2 page long code i'm pretty advanced, i'm able to do almost everything you said, even the memory management as vja said, the only problem is to start he array with those files already existing, I think is the contentsOfDirectoryAtPath:error method that i'm not being able to use well, can you point me somewhere to implement that code correctly?

Originally Posted by Duncan C

Use a method like contentsOfDirectoryAtPath:error to get a list of filenames (and folder names) from that subdirectory.

this is what i'm not able to do! thanks!

[Duncan C]

Originally Posted by JuanMazuera

thanks for your answer... actually of that 1/2 page long code i'm pretty advanced, i'm able to do almost everything you said, even the memory management as vja said, the only problem is to start he array with those files already existing, I think is the contentsOfDirectoryAtPath:error method that i'm not being able to use well, can you point me somewhere to implement that code correctly?



this is what i'm not able to do! thanks!

Here is some code I cut out of a Mac OS app I wrote a while back.

I did a quick-and-dirty edit on it to how what you need to do. It won't be perfect:

int				index;
NSError*		result;
NSArray*		theFilesArray = [fileMgr contentsOfDirectoryAtPath:documentsPath error: result];
//Check for errors here.
unsigned int	num_files = [theFilesArray count];
NSMutableArray* theImagesArray = [NSMutableArray arrayWithCapacity:10];
UIImage*		anImage;

for (index = 0;index < num_files; index++)	
{
	theName = [theFilesArray objectAtIndex: index];
	//NSLog(@"Path = %@", theName);
	thePath =  [documentsPath stringByAppendingPathComponent: theName];
	fileExists = [fileMgr fileExistsAtPath:thePath isDirectory: &isDirectory];
	if (fileExists && !isDirectory && [[thePath pathExtension] isEqualToString: @"png"])	//replace with the file extension you're using
	{
		anImage = [UIImage* imageWithContentsOfFile: thePath];
		if (anImage)
			[theImagesArray addObject: anImage];
	}
}

[JuanMazuera]

Originally Posted by Duncan C

Here is some code I cut out of a Mac OS app I wrote a while back.

I did a quick-and-dirty edit on it to how what you need to do. It won't be perfect:

int				index;
NSError*		result;
NSArray*		theFilesArray = [fileMgr contentsOfDirectoryAtPath:documentsPath error: result];
//Check for errors here.
unsigned int	num_files = [theFilesArray count];
NSMutableArray* theImagesArray = [NSMutableArray arrayWithCapacity:10];
UIImage*		anImage;

for (index = 0;index < num_files; index++)	
{
	theName = [theFilesArray objectAtIndex: index];
	//NSLog(@"Path = %@", theName);
	thePath =  [documentsPath stringByAppendingPathComponent: theName];
	fileExists = [fileMgr fileExistsAtPath:thePath isDirectory: &isDirectory];
	if (fileExists && !isDirectory && [[thePath pathExtension] isEqualToString: @"png"])	//replace with the file extension you're using
	{
		anImage = [UIImage* imageWithContentsOfFile: thePath];
		if (anImage)
			[theImagesArray addObject: anImage];
	}
}

Thank you very much for sharing this code, i'll try it and give my feedback, i'm still kind of slow at developing... still learning!