+2  A: 

Custom cell, either on that column or on a second column.

Peter Hosey  2009-06-01 18:11:18
Do you know where I might get it?
Joshua  2009-06-01 18:27:57
Get? You make it.
Peter Hosey  2009-06-01 19:02:16
Is there a web page where I might find some advice on how to make my own?
Joshua  2009-06-01 19:33:05
Sadly, no. There is a page titled “Subclassing NSCell”, but it's incomplete to the point of uselessness. Fortunately, it's not too difficult: Make a subclass of NSCell, implement one or both of the public drawing methods, and make it handle an object value that is an instance of one of your model classes.
Peter Hosey  2009-06-01 20:05:07
It would be even easier if you went the two-column route: the custom cell in the second column would only need only to be able to handle an NSNumber. The trick, though, would be sizing the second column correctly, which is why I'd do one-column and make my cell completely app-specific.
Peter Hosey  2009-06-01 20:07:10
I will give it go, and will try the two column route.
Joshua  2009-06-02 05:33:41
+3  A: 

You can either make a custom NSCell subclass that will show the child count (you would use your model object itself as the cell's object value, instead of providing a separate string or image), or in your data source method for the outline view you could just include the count along with the title string. Of course, you'll have to use the first option if you want it drawn exactly like the screenshot.

Marc Charbonneau  2009-06-01 18:39:16
How would i, in the data source method for the outline view could I include the count along with the title string?
Joshua  2009-06-01 18:57:28
Joshua: +[NSString stringWithFormat:]. As he says, though, simply formatting the number into the string won't make it look like the screenshot; you need a custom cell for that.
Peter Hosey  2009-06-01 19:04:13

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