Re: Undocumented Leopard support for overlapping sibling views

FROM : Ken Thomases
DATE : Fri Aug 29 00:25:19 2008

On Aug 28, 2008, at 4:46 PM, Andy Lee wrote:

> On Aug 28, 2008, at 5:09 PM, Ken Thomases wrote:
>

>> On Aug 28, 2008, at 3:28 PM, Nathan Vander Wilt wrote:
>>

>>> According to two list postings (http://lists.apple.com/archives/
>>> cocoa-dev/2007/Nov/msg01760.html, http://lists.apple.com/archives/
>>> cocoa-dev/2007/Nov/msg01764.html) both by Apple employees, 
>>> overlapping sibling subviews are fully supported in Leopard (and 
>>> presumably beyond).

>>
>> Interesting.  I hadn't noticed that discussion.  I'm glad you 
>> brought it to my attention.
>>

> [...]

>> Off to file a documentation bug...

>
> The NSView class reference says:
>
> addSubview:
> Adds a view to the receiver’s subviews so it’s displayed above its 
> siblings.
>
> [...]
>
> addSubview:positioned:relativeTo:
> Inserts a view among the receiver’s subviews so it’s displayed 
> immediately above or below another view.
>
>
> I don't remember if the z-ordering was documented as guaranteed 
> before.


It was.  I have a Tiger system with the old docs and those quotes 
were present -- and coexisted with the warnings that overlapping 
sibling views didn't guarantee correct clipping, invalidation, or 
drawing.  And so I took that documentation for the addSubview:... 
methods to mean very little. ;)  In other words, the z-order 
guarantee doesn't imply correctness of clipping, invalidation, or 
drawing.

Cheers,
Ken