image path from sqlite is not working - ios

Question

I'm practicing how to parse XML data and store it into the sqlite. I have done parsing and storing successfully. But I have one problem with displaying image from an url. The URL is formed by combining two NSStrings. One for the fixed address(which I set value) and other based on the name of the photo(retrieved from Sqlite). I am able to create complete URL by retrieving name of photo from Sqlite. But strange thing happen when I use that URL to display image in UIImageView. It does not work. After some testing, I found out there is something wrong with the portion(photo name) I retrieved from Sqlite. If I combine the fixed address with literal name of the photo, it works. Can somebody explain why it happens like this. Thanks in advance.
NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:#"user.db"];
FMDatabase * database = [FMDatabase databaseWithPath:defaultDBPath];
[database open];
results=[database executeQuery:#"SELECT * FROM plant WHERE name=?",self.plantname];
while([results next]) {
name = [results stringForColumn:#"name"];
category = [results stringForColumn:#"category"];
instructions = [results stringForColumn:#"instructions"];
price = [results stringForColumn:#"price"];
photo=[results stringForColumn:#"photo"];
}
NSString * fixedURL = #"http://services.hanselandpetal.com/photos/";
NSString *url=[fixedURL stringByAppendingString:photo];
NSLog(url);
NSURL * imgURL = [NSURL URLWithString:url];
NSData * imageData = [NSData dataWithContentsOfURL:imgURL];
UIImage * image = [UIImage imageWithData:imageData];
self.plantImageView.image=image;
Edit
I've edited based on Rob answer. But there are still problems. I put log below. I've already tried to remove white spaces by using [photo stringByReplacingOccurrencesOfString:#" " withString:#""]. But it does not seem to affect.
2014-10-15 02:12:39.505 SqlitePractice[9256:286525] url string = 'http:/services.hanselandpetal.com/photos/mona_lavender.jpg'
2014-10-15 02:12:39.506 SqlitePractice[9256:286525] imgURL = (null)
2014-10-15 02:12:39.516 SqlitePractice[9256:286525] sendAsynchronousRequest failed: Error Domain=NSURLErrorDomain Code=-1002 "unsupported URL" UserInfo=0x7a78ba50 {NSUnderlyingError=0x7a66b5e0 "unsupported URL", NSLocalizedDescription=unsupported URL}
Edit 2
The URL seems to be problem after changing from stringByAppendingString to stringByAppendingPathComponent. But I found out that even without one slash after http: , it works if I change the photo value. And the image is displayed.
NSString * fixedURL = #"http://services.hanselandpetal.com/photos/";
photo=#"bougainvillea.jpg";
NSString *url=[fixedURL stringByAppendingPathComponent:photo];
NSLog(#"url string = '%#'", url);
NSURL * imgURL = [NSURL URLWithString:url];
NSLog(#"imgURL = %#", imgURL);
And the log is below,
2014-10-15 12:07:56.650 SqlitePractice[9690:308022] url string = 'http:/services.hanselandpetal.com/photos/bougainvillea.jpg'
2014-10-15 12:07:56.651 SqlitePractice[9690:308022] imgURL = http:/services.hanselandpetal.com/photos/bougainvillea.jpg
Edit 3
I have changed based on Rob's modified answer.
NSURL *fixedURL = [NSURL URLWithString:#"http://services.hanselandpetal.com/photos/"];
NSURL *url = [fixedURL URLByAppendingPathComponent:[photo stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
NSLog(#"image URL = '%#'", url);
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
if (error) {
NSLog(#"sendAsynchronousRequest failed: %#", error);
return;
}
UIImage *image = [UIImage imageWithData:data];
self.plantImageView.image=image;
}];
And here is the log message:
2014-10-15 13:40:38.977 SqlitePractice[10436:357359] image URL = 'http://services.hanselandpetal.com/photos/camellia.jpg%250A%2520%2520%2520%2520'

Answer 1

A couple of thoughts:
Unrelated to your problem at hand, instead of stringByAppendingString, it's generally better to use URLByAppendingPathComponent with a NSURL. It takes care of adding any necessary / characters for you. Not critical given your example, but it's more robust.
Also, if the string might have spaces or other characters not permitted in a URL, you might percent escape it, too.
Thus, you'd do something like:
NSURL *fixedURL = [NSURL URLWithString:#"http://services.hanselandpetal.com/photos/"];
NSURL *url = [fixedURL URLByAppendingPathComponent:[photo stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
You should NSLog the NSURL variable and make sure it's not nil (e.g. which could be caused if there were some spaces in the photo string, for example, unless you percent escape it).
In your revised question, in which you share the log, the original URL string (before the conversion to the NSURL) is being reported as:
http:/services.hanselandpetal.com/photos/mona_lavender.jpg
That should be:
http://services.hanselandpetal.com/photos/mona_lavender.jpg
If imgURL is not nil, but imageData is, you might want to retrieve the image data in a manner that retrieves the error. For example, you could:
NSError *error = nil;
NSData *imageData = [NSData dataWithContentsOfURL:imgURL options:0 error:&error];
if (!imageData) {
NSLog(#"dataWithContentsOfURL failed: %#", error);
}
Bottom line, go through this one line at a time and identify precisely where it is going wrong.
As an aside, you generally would want to avoid using dataWithContentsOfURL, but instead use an asynchronous method:
NSURL *fixedURL = [NSURL URLWithString:#"http://services.hanselandpetal.com/photos/"];
NSURL *url = [fixedURL URLByAppendingPathComponent:[photo stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
NRURLRequest *request = [NSURLRequest requestWithURL:imgURL];
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
if (error) {
NSLog(#"sendAsynchronousRequest failed: %#", error);
return;
}
UIImage *image = [UIImage imageWithData:data];
self.plantImageView.image=image;
}];

Answer 2

I belive that UIIMAGEVIEW will not display Url as image path. I would sugest to try with UIWebView which would display web content (image or whole web page). This example is writen in objective-c.
self.myWebView = [[UIWebView alloc] initWithFrame:self.view.bounds];
self.myWebView.scalesPageToFit = YES ;
[self.view addSubview:self.myWebView];
NSURL *url = [NSURL URLWithString:#"http://services.hanselandpetal.com/photos/mona_lavender.jpg"];
NSURLRequest *request = [ NSURLRequest requestWithURL:url];
[self.myWebView loadRequest:request]