Question

So I have a function which gets an image from a URL which looks like this:

- (UIImage *) getImageFromURL:(NSString *)fileURL {
    UIImage * result;

    NSData * img_data = [NSData dataWithContentsOfURL:[NSURL URLWithString:fileURL]];
    result = [UIImage imageWithData:img_data];

    return result;
}

and then a function which saves the image from a UIImage Which looks like this:

    -(void) saveImage:(UIImage *)image withFileName:(NSString *)imageName ofType:(NSString *)extension inDirectory:(NSString *)directoryPath {
    if ([[extension lowercaseString] isEqualToString:@"png"]) {
        [UIImagePNGRepresentation(image) writeToFile:[directoryPath stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.%@", imageName, @"png"]] options:NSAtomicWrite error:nil];
    } else if ([[extension lowercaseString] isEqualToString:@"jpg"] || [[extension lowercaseString] isEqualToString:@"jpeg"]) {
        [UIImageJPEGRepresentation(image, 1.0) writeToFile:[directoryPath stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.%@", imageName, @"jpg"]] options:NSAtomicWrite error:nil];
        NSLog(@"Image named %@ wrote to %@", imageName, directoryPath);
    } else {
        NSLog(@"Image Save Failed\nExtension: (%@) is not recognized, use (PNG/JPG)", extension);
    }
}

The issue I am facing is that when I run a UIImage through the saveImage function I dont think it is saving the image. This is because when I check for a UIImage imageNamed:@”Documents/filenamesavedas.jpeg” it returns (null). The image does however download correctly.

Here is my Documents Directory path function:

- (NSString *)getDocumentsDirectoryPath {
    NSString * documentsDirectoryPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    NSLog(documentsDirectoryPath);
    return documentsDirectoryPath;
}

Here is where I am downloading and trying to save the image:

   dispatch_async(jsonQueue, ^{
        // check to see if data authenticate runs successfully. 
    NSString *documentsDirectoryPath = [util getDocumentsDirectoryPath];
    UIImage *imageToSave = [util getImageFromURL:[properties objectForKey:@"current_group_logoURL"]];
    [util saveImage:imageToSave withFileName:[properties objectForKey:@"home_venue_logo"] ofType:@"jpeg" inDirectory:documentsDirectoryPath];
    NSLog(@"Group Logo URL %@", [properties objectForKey:@"current_group_logoURL"]);
    NSLog(@"Current Group Image %@", [properties objectForKey:@"home_venue_logo"]);        
        UIImage *testToSeeItHasDownloaded = imageToSave;
        NSString *imageLocation = [documentsDirectoryPath stringByAppendingPathComponent:[properties objectForKey:@"home_venue_logo"]];
        NSData *data = [NSData dataWithContentsOfFile:imageLocation];
        UIImage *testToSeeImageHasSaved = [UIImage imageWithData:data];
        NSLog(@"testToSeeImagehasDownloaded: %@", testToSeeItHasDownloaded);
        NSLog(@"image location to save to: %@", imageLocation);
        NSLog(@"testToSeeImagehasSaved: %@", testToSeeImageHasSaved );    

    });

The Console returns this:

2012-10-22 16:27:45.642 asdaf[46819:1d807] Group Logo URL http://somesite.com/50a0e42619424ba551a956511c098656.jpeg
2012-10-22 16:27:45.642 asdaf[46819:1d807] Current Group Image 50a0e42619424ba551a956511c098656.jpeg
2012-10-22 16:27:45.649 asdaf[46819:1d807] testToSeeImagehasDownloaded: <UIImage: 0xb09ed50>
2012-10-22 16:27:45.649 asdaf[46819:1d807] testToSeeImagehasSaved: (null)

testToSeeImagehasSaved should return null. But what am I doing wrong? Thanks.

Answer 1

this line doesn’t look right to me:

UIImage *testToSeeImageHasSaved = [UIImage imageNamed: [@"Documents/" stringByAppendingString: [properties objectForKey:@"home_venue_logo"]]];

I think you have to do:

UIImage* image = [UIImage imageWithContentsOfFile:"YOUR_FILE_PATH"];

[UIImage imageNamed:"image_name"] is good only for images attached to your project