Setting the wallpaper - C / C++ / MFC Discussion Boards

Re: MFC DLL

Hamid_RT23-Jun-08 21:24

Hamid_RT

23-Jun-08 21:24

Do you wan to make your dlls on the c++ and use of them on the C#? yes

Re: MFC DLL

theCPkid23-Jun-08 22:26

theCPkid

23-Jun-08 22:26

>>For example, I have 5 dll for five different application?
What kind of applications are these??

You can export functions from a dll and then on every button click, you can call any function inside any dll. So, it is possible for you to make five dll and make each dlls export 1 function which you will call depending on which button is clicked.

the fruits of your success will be in direct ratio to the honesty and sincerity of your own efforts in keeping your own records, doing your own thinking and, reaching your own conclusions.
..surviving in autumn..in love with spring..

Re: MFC DLL [modified]

bhanu_850923-Jun-08 23:12

bhanu_8509

23-Jun-08 23:12

My application is for MPEG2 Transport Stream Analysis and Decoding of MPEG streams. I am developing this applications in vc++.

theCPkid wrote:
You can export functions from a dll and then on every button click, you can call any function inside any dll. So, it is possible for you to make five dll and make each dlls export 1 function which you will call depending on which button is clicked.

My dll has many functions with it, for example, I will develop the decoder as one dll. Please tell me is it possible to call the dll from the c# GUI application. Does it takes more memory during the init of the c# application ? Can we control all the functions in the dll from the c# app ?

Also advice whether to develop the decoder app as a executable and then call the exe from the c# app. Will this takes more memory while loading ?

Please kindly advice how to proceed (whether to use dll or exe).

Thank you very much. Expecting your kind reply

modified on Tuesday, June 24, 2008 7:18 AM

Re: MFC DLL

bhanu_850924-Jun-08 1:54

bhanu_8509

24-Jun-08 1:54

Can anyone help me for the above ?

Kindly,
Gaja

Re: MFC DLL

theCPkid24-Jun-08 2:19

theCPkid

24-Jun-08 2:19

DLLs are more efficient when it comes to memory usage.
See this link:
http://msdn.microsoft.com/en-us/library/dtba4t8b(VS.80).aspx

Your dll can export as many functions as it wants.
What do you mean by controlling a function? You call the function inside you dll and it will accept some input, transport stream, and gives back audio/video stream as output.

By the way, it does not matter right now whether you work on dll or exe as the decoding logic will remain same. So, you can start working on it till you get a better idea of it.

Good Luck.

Re: MFC DLL

bhanu_850925-Jun-08 1:53

bhanu_8509

25-Jun-08 1:53

Thank you very much for your reply. I have finished developing the application as MFC. Now I have MFC executable. But now I need to design a single GUI to control all the functions.

I dont develop the application as dll as of now it is available only as MFC executable. I also go through the VC++ windows application forms and found it is better for designing GUI.

Now my question is that, "Is it possible to migrate the VC++ MFC code into Windows application form". It will be very easy for me, if the above one is possible.

Please guide me. (I am only having little knowledge in Windows application forms. If I am not explaining you correctly means, please advice.)

Many thanks in advance.

Re: MFC DLL

theCPkid27-Jun-08 22:11

theCPkid

27-Jun-08 22:11

oh! I am sorry for the very late reply.

"Is it possible to migrate the VC++ MFC code into Windows application form"
> No. AFAIK, you cannot directly copy MFC code into C#. You will need to make significant changes as the two languages are different.

But you have no trouble. Just create a dll. For that, create an empty MFC dll using wizard, and then copy your mainframe, view and doc class (assuming you are using doc/view architecture in MFC application) directly into dll and write the functions you want to export in the one cpp file of dll created by wizard.

You wont need to do any changes in code to create dll. and then you can use this dll in your C# application.

Hope that helps.

Setting the wallpaper

theCPkid23-Jun-08 21:10

theCPkid

23-Jun-08 21:10

I am using IActiveDesktop:SetWallpaper function to set the wallpaper. My application generates a bitmap, say D:\image.bmp and then this image is set as wallpaper. The problem is when I edit this image.bmp and call set wallpaper again, the new picture is internally set but is not updated on desktop. I mean to display the new edited picture I need to go to properties->Desktop and then ask windows to load image again.

Is there any way to programmatically tell windows to reload the wallpaper image. I guess it just assumes that if path is same, then no need to reload the image?

Re: Setting the wallpaper

Hamid_RT23-Jun-08 21:23

Hamid_RT

23-Jun-08 21:23

I think WallpaperQ: A Wallpaper Management Tool[^] is helpfuls for you.

Re: Setting the wallpaper

theCPkid23-Jun-08 22:33

theCPkid

23-Jun-08 22:33

Hey, thanks for the useful link. The link you have given will be helpful to me in many other ways although the problem I had can be solved by passing AD_APPLY_FORCE flag to ApplyChanges function of IActiveDesktop interface. I was using AD_APPLY_ALL but it was not refreshing the desktop.

Re: Setting the wallpaper

Hamid_RT24-Jun-08 0:23

Hamid_RT

24-Jun-08 0:23

I glad my answer was helpful for you. Big Grin | :-D

Re: Setting the wallpaper

Jijo.Raj24-Jun-08 0:30

Jijo.Raj

24-Jun-08 0:30

You've to call IActiveDesktop::ApplyChanges( AD_APPLY_ALL ). For code snippet just refer this - http://weseetips.com/2008/04/27/how-to-change-the-desktop-wallpaper-programmatically/[^]

Regards,
Jijo.

_____________________________________________________

http://weseetips.com[^] Visual C++ tips and tricks. Updated daily.

Re: Setting the wallpaper

theCPkid24-Jun-08 2:38

theCPkid

24-Jun-08 2:38

IActiveDesktop::ApplyChanges( AD_APPLY_ALL ) alone wont do. You need to pass AD_APPLY_FORCE function to refresh the same picture. AD_APPLY_ALL do not include AD_APPLY_FORCE. Thanks for your reply.

Re: Setting the wallpaper

Jijo.Raj24-Jun-08 3:41

Jijo.Raj

24-Jun-08 3:41

ooh!

Thanks for the info!

Regards,
Jijo.

_____________________________________________________

http://weseetips.com[^] Visual C++ tips and tricks. Updated daily.

WM_KILLFOCUS problem

danginkgo23-Jun-08 20:59

danginkgo

23-Jun-08 20:59

In the main window callback function I get the WM_KILLFOCUS message when I click on the window, and only then I get the WM_SETFOCUS message.
Is that OK?
I thought that WM_KILLFOCUS message is sent to a window immediatly before it looses focus.
I want to register some values when the window has keyboard focus and unregister the values when the window looses focus.
How can I do that?

danginkgo

Re: WM_KILLFOCUS problem

SandipG 23-Jun-08 21:20

SandipG

23-Jun-08 21:20

do you have child controls on your main window??

Regards,
Sandip.

Re: WM_KILLFOCUS problem

danginkgo23-Jun-08 21:45

danginkgo

23-Jun-08 21:45

I have child controls on the main window.

danginkgo

Re: WM_KILLFOCUS problem

SandipG 23-Jun-08 21:49

SandipG

23-Jun-08 21:49

then probably WM_KILLFOCUS is for one of the child window which was having focus earlier.
Check the vlaue of wParam in WM_KILLFOCUS. It is a handle to new window which will get the focus.
You can verify that WM_KILLFOCUS was not for your main window by comparing wParam with your main window handle.

And to find which window lost the focus check value of wParam in WM_SETFOCUS.

Regards,
Sandip.

Re: WM_KILLFOCUS problem

danginkgo23-Jun-08 21:54

danginkgo

23-Jun-08 21:54

OK, but if the main window loses focus, doesn't it get the WM_KILLFOCUS message? I just have to unregister some hotkeys if the window loses focus. How can I do that?

danginkgo

Re: WM_KILLFOCUS problem

danginkgo23-Jun-08 22:04

danginkgo

23-Jun-08 22:04

How can I know when the main window loses focus?

danginkgo

Re: WM_KILLFOCUS problem [modified]

SandipG 23-Jun-08 22:26

SandipG

23-Jun-08 22:26

I dont have much idea about SDK, but Try this I hope it works,

WM_SETFOCUS: if the wParam is handle to your main window then it means that your window has lost the focus. (Unregister ur hot keys)

WM_KILLFOCUS: if wParam is handle to your main window then it means that your window is going to get the focus (register your hot keys).

If this doesnt work may be some one can correct as i am really not sure.

Ohh I forgot about HWND parameter of WindowProc.
I guess It will point to your main window whenever whenever WM_KILLFOCUS will be generated for it and similarly for SetFocus.

Regards,
Sandip.

modified on Tuesday, June 24, 2008 5:07 AM

Re: WM_KILLFOCUS problem

danginkgo24-Jun-08 0:34

danginkgo

24-Jun-08 0:34

I tried but it doesn't work.
For WM_SETFOCUS and WM_KILLFOCUS , the wParam is not the main window HWND.

Ex.

wParam = 0x000209fc

This->hwndView = 0x000209ee
hWnd = 0x000209ee (HWND parameter of WindowProc)

So, I can't register and unregister if I get those messages.

danginkgo

Re: WM_KILLFOCUS problem

SandipG 24-Jun-08 0:43

SandipG

24-Jun-08 0:43

did you manage to get it working it or not can you paste some code snippets for the same.

Regards,
Sandip.

Re: WM_KILLFOCUS problem

danginkgo24-Jun-08 0:50

danginkgo

24-Jun-08 0:50

This is the callback function for the main (view) window:

<br />
<br />
LRESULT CALLBACK FldViewWndProc (HWND   hWnd,<br />
                                 UINT   wMessage,<br />
                                 WPARAM wParam,<br />
                                 LPARAM lParam){<br />
PluginInstance* This;<br />
................................................<br />
 case WM_KILLFOCUS:<br />
   This = (PluginInstance*) GetWindowLong(hWnd, 0);<br />
   if((HWND)wParam==This->hwndView)<br />
     register hotkeys<br />
   break;<br />
<br />
<br />
case WM_SETFOCUS:<br />
   This = (PluginInstance*) GetWindowLong(hWnd, 0);<br />
   if((HWND)wParam==This->hwndView)<br />
     unregister hotkeys<br />
   break;<br />
..................................................<br />
}<br />

danginkgo

Re: WM_KILLFOCUS problem

SandipG 24-Jun-08 0:57

SandipG

24-Jun-08 0:57

are you getting the same values in both cases you mentioned in your previous reply.

Regards,
Sandip.

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