.NET DateTimePicker and WM

.NET DateTimePicker and WM_NOTIFY

I'm a bit new to the Windows API, and I'm looking for help with how to
use it.

When looking through the source code of the .NET Framework
DateTimePicker control, I found it creates an instance of the
DateTimePicker common control using Windows API functions.  When I try
to trap the WM_NOTIFY message by overriding the WndProc method of the
DateTimePicker, I can check the NMHDR in the LParam for Codes.
However, the NMHDR codes do not correspond to the proper Codes in
CommCtrl.h.  For instance:
Up/Down: -949/-950
Moving between dates: -749,
Finally selecting a date: -746.
Tooltips:  -521/-522.

However, if I use the NativeWindow to subclass the Panel containing my
DateTimePicker, I am able to trap the right codes in the WndProc of
the NativeWindow.  Still, I do not receive any WM_NOTIFY messages if I
subclass the Form containing the Panel, or the DateTimePicker itself.

So I have two questions:

1:  Why does the .NET framework have different NMHDR codes for the
DateTimePicker, and where do I find a list of what they correspond to?

2.  Why do I need to subclass the Panel containing the DateTimePicker
instead of the DateTimePicker itself or the Form containing both of
them?

date: Tue, 24 Jun 2008 19:45:09 -0700 (PDT) author: andspal

Re: .NET DateTimePicker and WM_NOTIFY

Are the codes different for Unicode and non-Unicode?


"andspal"  wrote in message 
news:064a4c95-6707-44a8-ad7e-57436358e32e@r66g2000hsg.googlegroups.com...
> I'm a bit new to the Windows API, and I'm looking for help with how to
> use it.
>
> When looking through the source code of the .NET Framework
> DateTimePicker control, I found it creates an instance of the
> DateTimePicker common control using Windows API functions.  When I try
> to trap the WM_NOTIFY message by overriding the WndProc method of the
> DateTimePicker, I can check the NMHDR in the LParam for Codes.
> However, the NMHDR codes do not correspond to the proper Codes in
> CommCtrl.h.  For instance:
> Up/Down: -949/-950
> Moving between dates: -749,
> Finally selecting a date: -746.
> Tooltips:  -521/-522.
>
> However, if I use the NativeWindow to subclass the Panel containing my
> DateTimePicker, I am able to trap the right codes in the WndProc of
> the NativeWindow.  Still, I do not receive any WM_NOTIFY messages if I
> subclass the Form containing the Panel, or the DateTimePicker itself.
>
> So I have two questions:
>
> 1:  Why does the .NET framework have different NMHDR codes for the
> DateTimePicker, and where do I find a list of what they correspond to?
>
> 2.  Why do I need to subclass the Panel containing the DateTimePicker
> instead of the DateTimePicker itself or the Form containing both of
> them?
>

date: Tue, 24 Jun 2008 23:03:55 -0700 author: Sam Hobbs _change_social_to_socal

Re: .NET DateTimePicker and WM_NOTIFY

andspal wrote:
> I'm a bit new to the Windows API, and I'm looking for help with how to
> use it.
> 
> When looking through the source code of the .NET Framework
> DateTimePicker control, I found it creates an instance of the
> DateTimePicker common control using Windows API functions.  When I try
> to trap the WM_NOTIFY message by overriding the WndProc method of the
> DateTimePicker, I can check the NMHDR in the LParam for Codes.
> However, the NMHDR codes do not correspond to the proper Codes in
> CommCtrl.h.  For instance:
> Up/Down: -949/-950
> Moving between dates: -749,
> Finally selecting a date: -746.
> Tooltips:  -521/-522.
> 
> However, if I use the NativeWindow to subclass the Panel containing my
> DateTimePicker, I am able to trap the right codes in the WndProc of
> the NativeWindow.  Still, I do not receive any WM_NOTIFY messages if I
> subclass the Form containing the Panel, or the DateTimePicker itself.
> 
> So I have two questions:
> 
> 1:  Why does the .NET framework have different NMHDR codes for the
> DateTimePicker, and where do I find a list of what they correspond to?
> 
> 2.  Why do I need to subclass the Panel containing the DateTimePicker
> instead of the DateTimePicker itself or the Form containing both of
> them?

Aren't wm_notify messages sent to the parent, so you are receiving the 
dropdown monthviews notifications.

Try wm_reflect I think.

-- 
Dean Earley (dean.earley@icode.co.uk)
i-Catcher Development Team

iCode Systems

date: Wed, 25 Jun 2008 08:52:46 +0100 author: Dean Earley

Re: .NET DateTimePicker and WM_NOTIFY

"Dean Earley"  wrote in message 
news:ORZc2hp1IHA.4848@TK2MSFTNGP05.phx.gbl...
>
> Try wm_reflect I think.

No such thing. MFC does reflection but the Windows API does not reflect.

date: Thu, 26 Jun 2008 01:40:34 -0700 author: Sam Hobbs _change_social_to_socal

Re: .NET DateTimePicker and WM_NOTIFY

Sam Hobbs wrote:
> "Dean Earley"  wrote in message 
> news:ORZc2hp1IHA.4848@TK2MSFTNGP05.phx.gbl...
>> Try wm_reflect I think.
> 
> No such thing. MFC does reflection but the Windows API does not reflect. 

I can't remember the full details, but when I subclassed the common 
controls themselves (rather than the parent), I was picking up WM_NOTIFY 
| 0x2000.
I don't know what message this really is, but the original source I sued 
referred to it as WM_REFLECT.

As far as I'm aware, MFC doesn't come into any of this code as it is the 
Windows Common Controls being used in VB6.

-- 
Dean Earley (dean.earley@icode.co.uk)
i-Catcher Development Team

iCode Systems

date: Thu, 26 Jun 2008 12:39:20 +0100 author: Dean Earley

Re: .NET DateTimePicker and WM_NOTIFY

That makes sense, thanks a lot!

date: Mon, 30 Jun 2008 19:12:19 -0700 (PDT) author: andspal

Re: .NET DateTimePicker and WM_NOTIFY

"Dean Earley"  wrote in message 
news:ONckHF41IHA.552@TK2MSFTNGP06.phx.gbl...
> Sam Hobbs wrote:
>> "Dean Earley"  wrote in message 
>> news:ORZc2hp1IHA.4848@TK2MSFTNGP05.phx.gbl...
>>> Try wm_reflect I think.
>>
>> No such thing. MFC does reflection but the Windows API does not reflect.
>
> I can't remember the full details, but when I subclassed the common 
> controls themselves (rather than the parent), I was picking up WM_NOTIFY | 
> 0x2000.
> I don't know what message this really is, but the original source I sued 
> referred to it as WM_REFLECT.
>
> As far as I'm aware, MFC doesn't come into any of this code as it is the 
> Windows Common Controls being used in VB6.

I cannot find any documentation of WM_REFLECT as a message. That symbolic 
name is used as a base value that is added to other message ids, but I do 
not see WM_REFLECT documented as a message.

I searched the Windows SDK headers for WM_REFLECT and found nothing in 
there. It is not a Windows API message.

I did find a lot of .Net code using "WM_REFLECT + WM_NOTIFY" and stuff such 
as that. I am not familiar with .Net but I assume that it is using the value 
WM_REFLECT internally. This newsgroup however is the Windows API UI 
newsgroups and for the purposes of that subject, there is no such thing as a 
WM_REFLECT messge.

Or have you found documenttion indicating otherwise?

date: Mon, 30 Jun 2008 17:57:22 -0700 author: Sam Hobbs _change_social_to_socal

Re: .NET DateTimePicker and WM_NOTIFY

After making a search online regarding Dean's comment about the
WM_REFLECT, I found this site explaining the origins of WM_REFLECT:

http://www.eggheadcafe.com/forumarchives/vclanguage/Aug2005/post23538255.asp

It is a combination of OCM_BASE and WM_USER

Then, WM_NOTIFY is added to that sum, and if I catch the Messages to
the DateTimePicker with that number, I am able to receive the proper
-754 and -753 NMHDR codes.

date: Thu, 3 Jul 2008 11:47:00 -0700 (PDT) author: andspal