使用URL设置UIImageView

Question

I am setting image in UIImageView using:

[self.imageView setImageWithURL:[NSURL URLWithString:urlString] placeholderImage:[UIImage imageNamed:@"random_image"]];

I am able to see the image on phone as expected.

However, if I use the method without placeholder argument

[self.imageView setImageWithURL:[NSURL URLWithString:urlString]];

OR pass the placeholderImage as nil

[self.imageView setImageWithURL:[NSURL URLWithString:urlString] placeholderImage:nil];

then the image is not set and my imageView is blank. I understand that placeholder image is for " representing the current state of the asset suitable for temporarily displaying in your extension's UI. ".

I don't understand how its absence should impact me the way it is impacting. Any pointers?

Answer 1

If you set default placeholder image then imageview gets width and night.Otherwise imageview frame is may be (0,0).

Or

The image should be downloaded asynchronously using NSURLConnection, and only once it's fully downloaded should it be converted into a UIImage and assigned to the image view

[NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:imageUrl]] queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {

ImageViewName.image = [UIImage imageWithData:data];

}];

Answer 2

I found the issue. I added an image view in UITableViewCell with the name imageView . Apparently, UITableViewCell already has a property with the same name. I changed the name of myImageView to cellImageView and now, I don't need the placeholder parameter anymore! Having said that, I still don't understand what happened behind the screens!

Answer 3

i hope these code will help u....

dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
    dispatch_async(queue, ^{

        UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:
                                                 [NSURL URLWithString:@“image URL”]]];
        dispatch_sync(dispatch_get_main_queue(), ^{

                [[cell myimage] setImage:image];

            }
         });
    });