I need to set the height for the Cells based on the height of the uiimageview which is `scaledHeight` variable
im getting images from Parse like so in my cellForRowAtIndexPath

```
PFFile *userImageFile = object[@"image"];
    [userImageFile getDataInBackgroundWithBlock:^(NSData * _Nullable data, NSError * _Nullable error) {
        if (!error) {
           // UIImageView *imageView = (UIImageView *)[cell viewWithTag:1];
            UIImage *image = [UIImage imageWithData:data];
           // imageView.image = image;

            UIImageView *test = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 400, 320)];
            test.image = image;

            CGSize imgSize = image.size;
            CGFloat ratio = test.frame.size.width/imgSize.width;
            CGFloat scaledHeight = imgSize.height * ratio;

            [test setFrame:CGRectMake(0, 0, self.view.window.frame.size.width, scaledHeight)];

            NSLog(@"HEIGHT:%f",scaledHeight);

            [cell addSubview:test];

        }
    } progressBlock:^(int percentDone)
    {

    }];

```

how can i set `scaledHeight` inside `heightForRowAtIndexPath` as `heightForRowAtIndexPath` is run before `CellForRowAtIndexPath`?