Resize UIImageView in UITableViewCell

Question

I have a 16x16 pixel image that I want to display in an UIImageView. So far, no problem, however 16x16 is a bit small so I want to resize the image view to 32x32 and thus al

Answer 1

You need to override the layoutSubviews method. By default, it's resizing the imageview based on the cell height size.

-(void)layoutSubviews
{
    [super layoutSubviews];

    self.imageView.frame = CGRectMake(self.imageView.frame.origin.x,
                                      self.imageView.frame.origin.y,
                                      MY_ICON_SIZE,
                                      MY_ICON_SIZE);
}

You'll probably want to recalculate the origin as well so it's vertically centered.

Answer 2

I have successfully made it using CGAffineTransformMakeScale!

cell.imageView.image = cellImage;
//self.rowWidth is the desired Width
//self.rowHeight is the desired height
CGFloat widthScale = self.rowWidth / cellImage.size.width;
CGFloat heightScale = self.rowHeight / cellImage.size.height;
//this line will do it!
cell.imageView.transform = CGAffineTransformMakeScale(widthScale, heightScale);

Answer 3

Using CGAffineTransformMakeScele as @ahmed said is valid and do not seems to be duck type solution at al! For instance, if you have a large image and put it into a UITableViewCell (say the image is 2x larger than the one that fits into a table cell. If you scale by 0.9 you don't see any result. Only if you scale by less than 0.5 (because 0.5*2.0 = 1.0 that is the size of the cell). So it seems that inside the api, apple is doing exactly that.

Answer 4

I think you need to set the contentMode:

cell.imageView.contentMode = UIViewContentModeScaleAspectFit;

In context:

UIImage *image = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"slashdot" ofType:@"png"]];
imageView = [[UIImageView alloc] initWithImage:image];
[imageView setBackgroundColor:[UIColor greenColor]];
[imageView setFrame:CGRectMake(x,y,32,32)];
imageView.contentMode = UIViewContentModeScaleAspectFit;    
[self.view addSubview:imageView];

Note: I've set a background colour so you can debug the on-screen boundaries of the UIImageView. Also x and y are arbitrary integer coordinates.