[Adobe-source-devel] Re: asl-users: Widget Parenting Issues

[Tom P. <tpi...@ad...>]

And it was also brought to my attention that you can indeed re-parent a Qt
widget that is initially created with a NULL parent - very good to know. The
only question then is whether there's any significant overhead involved if
this means each such widget is first created as a platform window and then
changed to a child view when re-parented. I'll guess I'll cross that
bridge...

Thanks,

Tom


> If it helps with implementation issues, you can easily reparent a Window
> to another parent using SetParent() (at least within the same process).
>   I suspect all controls could start with the same parent - an invisible
> window hiding somewhere, and then be reparented 'when the time is right'.
> 
> 
> Tony Van Eerd
> Adobe Waterloo
> -via Thunderbird-
> 
> Tom Pinkerton wrote:
>> Hi All,
>> 
>> While digging into my Qt implementation of the widgets library, I've noticed
>> that a widget's parent appears to be set after the underlying platform
>> widget itself is created. On MacOS this is not a problem because a control
>> can be initially created without a parent. However, the existing Windows
>> implementation uses some kind of 'invisible parent' member as an initial
>> parent when a control is created. In Qt, like on Windows, a widget needs a
>> parent at creation time, so I'm wondering if I will need a similar
>> 'invisible parent' mechanism for my Qt implementation. Does Eve somehow rely
>> upon setting the parent after a widget is initially created? Is the sole
>> purpose of the display_t object to provide a way to set the widget's parent
>> hierarchy? Will the parent hierarchy ever change for a given Eve layout
>> after the initial layout is created?
>> 
>> Thanks,
>> 
>> Tom