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General Discussion

Posted by Arsene Lavaux
Arsene Lavaux
4,342 Points

Issue loading image message in ImageViewController

As part of the Ribbit app, when I click in the InboxViewController on an image message, the screen on my iPhone freezes, with the selected row greyed out and I get this message:

2014-02-21 12:40:06.629 Ribbit_Start[362:60b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSURL initWithString:relativeToURL:]: nil string parameter'

I do have the test on the message type in InboxViewController to launch the "showImage" segue (I also double checked in the Storyboard that the Segue Identifier is set to showImage) when the image fileType is identified with the message:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    self.selectedMessage = [self.messages objectAtIndex:indexPath.row];
    NSString *fileType = [self.selectedMessage objectForKey:@"fileType"];
    if ([fileType isEqualToString:@"image"]) {
        [self performSegueWithIdentifier:@"showImage" sender:self];
    }

In the ImageViewController implementation file, I have the following code:

#import "ImageViewController.h"

@interface ImageViewController ()

@end

@implementation ImageViewController


- (void)viewDidLoad
{
    [super viewDidLoad];
    PFFile *imageFile = [self.message objectForKey:@"file"];
    NSURL *imageFileUrl = [[NSURL alloc] initWithString:imageFile.url];
    NSData *imageData = [NSData dataWithContentsOfURL:imageFileUrl];
    self.imageView.image = [UIImage imageWithData:imageData];

    NSString *senderName = [self.message objectForKey:@"senderName"];
    NSString *title = [NSString stringWithFormat:@"Sent from %@", senderName];
    self.navigationItem.title = title;

}


@end

And here is my header for ImageViewController:

#import <UIKit/UIKit.h>
#import <Parse/Parse.h>

@interface ImageViewController : UIViewController
@property (nonatomic,strong) PFObject *message;


@property (weak, nonatomic) IBOutlet UIImageView *imageView;

@end

Looking forward to your expertise.

A passionate beginner :)