Re: How do I get access to the control within a NSToolbarItem?
Re: How do I get access to the control within a NSToolbarItem?
- Subject: Re: How do I get access to the control within a NSToolbarItem?
- From: Daryle Walker <email@hidden>
- Date: Sun, 03 Aug 2014 16:12:02 -0400
On Aug 3, 2014, at 3:35 PM, Jens Alfke <email@hidden> wrote:
> On Aug 3, 2014, at 11:56 AM, Daryle Walker <email@hidden> wrote:
>>
>> I just noticed that myself. Is “(NSSegmentedControl *)self.toolbarBackForward.view”, a cast to a (2 layers down) subclass, the way you’re supposed to access the control’s stuff? It looks like a hack, but I’ll take it since it (seemingly) works.
>
> Sure. Why is casting to a subclass a hack? It’s a fact of life in a statically-typed language. (You’re implicitly casting to subclasses all the time, like whenever you access objects in a collection; it’s just that the ‘id’ type saves you the trouble of explicitly having to write the cast. If anything, in this case it’s actually a safer cast since you know the object is a view, whereas with id it could be anything at all.)
It’s my understanding of Objective-C. I thought you could do:
[self.toolbarBackForward.view methodOfNSSegmentedControl:blah-blah-blah]
without complaint. I know that NSView doesn’t have that method, but the actual object taking this at runtime is a subclass that does have the desired method. I thought the compiler will ignore that fact with a warning instead of an error. Is this something reserved only when using “id” as the static-time pointer type? Am I misremembering seeing Objective-C code that lets this sort of stuff through at compile-time because of saving it for run-time?
—
Daryle Walker
Mac, Internet, and Video Game Junkie
darylew AT mac DOT com
_______________________________________________
Cocoa-dev mailing list (email@hidden)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden