iOS ViewWillAppear Won't Load Image.

[loon3y]

i have a barcode scanning app, and i have an image view showing the picture of the recently scanned item, through a web service. it worked in the beginning, but after i changed something a while back it stopped showing up. now I'm trying to fix this problem. in only appears when i go out of the view controller (via tab bar) and go back in, here is my viewWillAppear code:

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    
    // use the product code for image, even if UPC is scanned
    NSString *sURL = [[NSString alloc] initWithString:[NSString stringWithFormat:@"http://******.*****.com:90/prodimage/%@.jpg", displayText.text]];
    NSData *mydata = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@",sURL]]];
    UIImage *image = [[UIImage alloc] initWithData:mydata];
    [invenImage setImage:image];
}

 

[cMacSW]

Try telling the image view needsDisplay

[yourImageView setNeedsDisplay:YES];

 

[loon3y]

Try telling the image view needsDisplay

[yourImageView setNeedsDisplay:YES];

thanks but it didnt work, i running Xcode 4.3.1, so i don know if its the new version but there isn't a boolean after the code in my Xcode.





is there a method or function where i can refresh/reload the image that i can add at the end of viewWillAppear?

 

[cMacSW]

is there a method or function where i can refresh/reload the image that i can add at the end of viewWillAppear?

That's what setNeedsDisplay should do.

 

[loon3y]

That's what setNeedsDisplay should do.

damn it, it worked before no problem, but after a co worker changed some coding in another view controller (using global variables) it stopped working.

 

[cMacSW]

Did you confirm that this is being called the first time the view is displayed by setting a breakpoint?

----------

Also, not related to your problem, but this line:

NSString *sURL = [[NSString alloc] initWithString:[NSString stringWithFormat:@"http://******.*****.com:90/prodimage/%@.jpg", displayText.text]];

could be changed to this:

NSString *sURL = [NSString stringWithFormat:@"http://******.*****.com:90/prodimage/%@.jpg", displayText.text];

 

[larswik]

cMacSW - I was reading this thread and was also wondering in the begining why he did not just use 'stringWithFormat'.

loon3y - When I develop problems like this I NSLog after every line of code to check to make sure my results are what I expected them to be.

 

[dejo]

loon3y - When I develop problems like this I NSLog after every line of code to check to make sure my results are what I expected them to be.

I'd suggest it's easier to just set a breakpoint and step through / into every line of code.

 

[cMacSW]

The docs says there are situations where viewWillAppear will not be called, that's why setting a break point may help here.

 

[loon3y]

Resolved:



basically i shouldn't of called the image in my barcode function or viewWillAppear or viewDidAppear.






i had to put it in my XML parse section of the code, because when I'm calling the image I'm using a store specified product code rather than calling it by the UPC when i scan. ( i know it should be either or but everything is mickey mouse and going to cleanup/optimize it later)

- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName 
  namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName 
{
    
    if ([elementName isEqualToString:@"itemno"])
    {
        displayText.text = capturedCharacters;
        
        // display the image on 1st viewcontroller
        NSString *sURL = [[NSString alloc] initWithString:[NSString stringWithFormat:@"http://*****.******.com:90/prodimage/%@.jpg", capturedCharacters]];
        NSData *mydata = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@",sURL]]];
        UIImage *image = [[UIImage alloc] initWithData:mydata];
        [invenImage setImage:image];
        [invenImage setNeedsDisplay];
    }
 
    [capturedCharacters release];
    capturedCharacters = nil;
    
    if ([elementName isEqualToString:@"str_partinfo"]) {
        // We are no longer in an item element
        inItemElement = NO;
    }
}

hope this helps out anyone that gets confused using lineapro