Question

I wrote a simple program to help me debug.

#import "UIImage+saveScreenShotOnDisk.h"

@implementation UIImage (saveScreenShotOnDisk)

-(void)saveScreenshot{
    NSData * data = UIImagePNGRepresentation(self);
    [data writeToFile:@"foo.png" atomically:YES];
}

@end

After it’s executed, I want to know where foo.png is located.

I went to

~Library/Application Support

and I can’t find foo.png. Where is it?

If I do

BOOL result = [data writeToFile:@"foo.png" atomically:YES];

the result will be NO, which is kind of strange given that the simulator, unlike the iPhone, can write anywhere.

Answer 1

You need to direct the NSData object to the Path you want the data to be saved in:

NSString *docsDir;
NSArray *dirPaths;

dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
docsDir = [dirPaths objectAtIndex:0];
NSString *databasePath = [[NSString alloc] initWithString: [docsDir stringByAppendingPathComponent:@"foo.png"]];
[data writeToFile:databasePath atomically:YES];

This will save your file in your App’s Folder on the device (or the simulator).