UITableViewCell's imageView fit to 40x40

Question

I use the same big images in a tableView and detailView. Need to make imageView filled in 40x40 when an imags is showed in tableView, but stretched on a half of a screen. I

Answer 1

I cache a thumbnail version since using large images scaled down on the fly uses too much memory.

Here's my thumbnail code:

- (UIImage *)thumbnailOfSize:(CGSize)size {
    if( self.previewThumbnail )
        return self.previewThumbnail; // returned cached thumbnail

    UIGraphicsBeginImageContext(size);

    // draw scaled image into thumbnail context
    [self.preview drawInRect:CGRectMake(0, 0, size.width, size.height)];

    UIImage *newThumbnail = UIGraphicsGetImageFromCurrentImageContext();    

    // pop the context
    UIGraphicsEndImageContext();

    if(newThumbnail == nil) 
        NSLog(@"could not scale image");

    self.previewThumbnail = newThumbnail;

    return self.previewThumbnail;
}

Just make sure you properly clear the cached thumbnail if you change your original image (self.preview in my case).