Re: Subclassed control in IB uses original cell class

FROM : Corbin Dunn
DATE : Wed Nov 28 22:23:00 2007

On Nov 28, 2007, at 12:48 PM, David Hoerl wrote:

> I found a neat double knobbed slider on the web: http://developer.snowmintcs.com/controls/smdoubleslider/
>
> There is only a IB2 palette, so I figured I'd just add a NSSlider 
> object to my NIB, change its class to SMDoubleClass, then do 
> anything further in awakeFromNib.
>
> The problem is that the control ends up with a NSSliderCell and not 
> a SMDoubleSliderCell - guess +cellClass does not get invoked for 
> archived objects.
>
> At first, I could not subclass the cell as a nib2.x file does not 
> support it. However, the IB3 docs say I can use the nib3.x file on 
> Tiger (for building only, not editing). So, I changed formats, 
> changed the cell class, and now all is working as expected.
>
> I was wondering though - suppose I had to stay with IB2 - how would 
> I get the correct class of cell?
>


Do something like this (which you probably want to do anyways, if you 
create an instance of SMDoubleClass in code):

+ (void)initialize
{
    if (self == [SMDoubleClass class]) {
        [self setCellClass:[SMDoubleSliderCell class]];
    }
}

Also, I'd recommend a better classname: SMDoubleSlider is more 
descriptive :)

corbin