使用SDWebImage缓存图像

Question

I'm very new to IOS development. Now, I want to cache all my images I get back from my webservice. I am saving all the urls in my core database. When I nee to fill a tableview I get the data from my core database, and put it in the tableview. Now I want to cache this pictures. After some google searching. I found the SDWebImage.

I'm using it at this way in my tableview.

[cell.img_Picture setImageWithURL:[NSURL URLWithString:news.url]
                        placeholderImage:[UIImage imageNamed:@"placeholder.png"]];

But it is not showing this image. My imageview keeps blank. I imported the SDWebImage framework correctly and followed all the steps on the github page to install it.

But can anybody tell me what I'm doing wrong ?

Thanks in advance

Answer 1

So you don't even see the placeholder.png image? Do you actually have a placeholder.png image added to your project?

Have you tried logging the url that you've retrieved and checking that it is in fact valid (plug it into your browser)?

NSLog(@"%@", news.url);

You could also try logging the frame of your image_view:

NSLog(@"Cell Frame x: %f, y: %f, w: %f, h: %f", cell.img_Picture.origin.x, cell.img_Picture.origin.y, cell.img_Picture.size.width, cell.img_Picture.size.height);