Images in UITableView keep re-loading and wrong images flash while scrolling

Question

i have created a UITableView which populates each cell from URL requests. I have used \'dispatch_queue\' to prevent the UItableView from freezing. For some reason when i s

Answer 1

When you scroll your table every time your image will download again. to prevent this i prefer you to get image from cache and set in your imageview directly. so as per your code. if you scroll from 0 index to 10 then cell will download image for all 10 cells. after that if you scroll again 10 to index 0 . then image will be download again.

you can use (https://github.com/rs/SDWebImage) to download image async. its very easy and fast.

i prefered this library because it will handle your cache. just write below code

#import "UIImageView+WebCache.h"

// in cellForRowAtIndexPath.
[customCell.customCellImageView sd_setImageWithURL: [NSURL URLWithString:urlString]];

remove below code.

dispatch_queue_t imageQueue = dispatch_queue_create("imageDownloader",nil);
    dispatch_async(imageQueue, ^{

        NSData *data = [[NSData alloc] initWithContentsOfURL:urlString];

        dispatch_async(dispatch_get_main_queue(), ^{

            customCell.customCellImageView.image = [UIImage imageWithData: data];
        });
    });

Maybe this will help you.