Need help on subclassing windows - C / C++ / MFC Discussion Boards

Re: Does anything affect Sleep ()

Toby Opferman11-May-04 12:53

Toby Opferman

11-May-04 12:53

BTW, Sleep() calls SleepEx with FALSE.

Re: Does anything affect Sleep ()

Rafael Fernández López11-May-04 4:50

Rafael Fernández López

11-May-04 4:50

Well.. TEST IT !! Poke tongue | ;-P

You can send a MessageBox after the Sleep() function, so if you start back up again and the message is on your screen it means that it worked.

I think is the best option... Wink | ;)

Written by: Rafael Fernández López.

Visit: http://www.maestroprogramador.com

Re: Does anything affect Sleep ()

cheesepirate11-May-04 4:53

cheesepirate

11-May-04 4:53

I'm inclined to agree - just I got an attack of lazyitis and didn't want to hibernate a pc Smile | :)

CopyFile help!

Ryan McDermott11-May-04 4:34

Ryan McDermott

11-May-04 4:34

I need source code for a program that copies itself into a certain directory with a certain name like "C:\Program Files\something.exe"

-Ryan M.

Re: CopyFile help!

Rafael Fernández López11-May-04 4:54

Rafael Fernández López

11-May-04 4:54

I'm not sure if an app that is running can be copied itself or even can be copied by other process...

Written by: Rafael Fernández López.

Visit: http://www.maestroprogramador.com

Re: CopyFile help!

Diddy11-May-04 5:51

Diddy

11-May-04 5:51

It can - like this:

TCHAR szFileName[MAX_PATH];
::GetModuleFileName(szFileName, MAX_PATH];

LPCTSTR pszDest = _T("C:\\Program Files\\SomeApp.exe");
::CopyFile(szModuleFileName, pszDest);

Re: CopyFile help!

ThatsAlok3-May-05 22:12

ThatsAlok

3-May-05 22:12

look for [ShFileOperation] api!

"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow

cheers,
Alok Gupta

Need help on subclassing windows

cnurse11-May-04 3:19

cnurse

11-May-04 3:19

Hi guys,

I've developed in C++ for many years, but more recently have been working in C# and VB.NET.

I am developing my own version of themed controls where the user can govern just about any aspect of control drawing, like shape and colour etc.

I want to extend this control now to Windows Captions (i.e. Form captions). One thing that I have never fully gained is an understanding of what windows messages to trap, whether to let the default processing always take place, and what values to return. Even when I think I am following the MSDN SDK documention on WM_... notifications I still can't seem to get it right.

My problem seems to mainly be in getting setup, i.e. calling GetWindowDC to give me the entire drawing area of the window. Once I have called GetWindowDC I can construct a .NET Graphics object, and later dispose of both after my drawing is complete.

I do this and clear the Graphics object to red, so I should see all the non-client area turn red, which happens when the window is first drawn, but after that, as I start to move the window or size it I dont see the DC get consistently filled with red.

In summary then, if I could get a control of non-client drawing then I would have raised my programming standard significantly.

I would really be immensley greatful if you guys could point me at a definitive guide to subclassing or window's message processing, without recommending 3rd part controls as I am a DIY fanatic! 8-)

Also, if any of you can spare some time now and again, perhaps on MSN messenger to chat about this issue that would just be solid gold.

I await your responses with baited breath!

Thanks all!

Nursey

Re: Need help on subclassing windows

Hesham Amin11-May-04 4:12

Hesham Amin

11-May-04 4:12

Override the OnMessage method which recieves a Message structure.

Re: Need help on subclassing windows

cnurse11-May-04 13:53

cnurse

11-May-04 13:53

Thanks but I know how to get to the messages. As I said the problem has always been what messages to process. To be specific, what messages do I have to trap and process if I want to take entire responsibility for NC processing/drawing? Do I always have to perform the default processing then do my thing?

See?

Thanks.

Nursey

List control events

jhorstkamp11-May-04 2:54

jhorstkamp

11-May-04 2:54

All,

History:
I have a list control that I used the onclick event to perform action with.
The user wanted to be able to use the up/down arrows so I changed the event handler to use the itemchanged message.

Now:
The user wants to use both the mouse and the arrows - which is fine since the itemchanged message takes care of both of these actions. The problem being that the user also wants to be able to reperform (if that's a word)
the same actions (it's a function to do a lot of number crunching on some data) on the currently selected item. The problem is that the itemchanged message gets called 3 times and thus the number crunching takes place 3 times!
How do I get this to handle both mouse clicks and up/down arrows without having my function called 3 times?

Thanks in advance,

John

Re: List control events

Monty²11-May-04 3:02

Monty²

11-May-04 3:02

the function is called three times for the selected and the item that is being unselected(if thats a word Smile | :)

)

so i am going by memory here
it is called once when the previously selected item is Unselected, then for the new item that is selected and the the newly selected item gains focus rect

examin the NM_LISTVIEW structure that is passed it contains the ItemNo and the Reason(selected, unselected etc) and then perform ur action

Hope it helps Smile | :)

C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg

Re: List control events

Diddy11-May-04 3:11

Diddy

11-May-04 3:11

Like this (I think)

void CYourDialog::OnClickList2(NMHDR* pNMHDR, LRESULT* pResult)
{
LPNMLISTVIEW pnmv = (LPNMLISTVIEW) pNMHDR;
if(pnmv->uNewState & LVIS_SELECTED)
{
// do long running stuff
}
}

Re: List control events

jhorstkamp11-May-04 8:13

jhorstkamp

11-May-04 8:13

Thanks - that almost works...

It fails when I want to click on an already selected item and process data.
(I'm varying some algorithm params in the dialog and observing the effect).

So, I guess all I really want to do is to be able to use the up/down arrows to scroll and automatically process AND be able to use the mouse click to randomally select list data as well as process an already selected item.

Is this the correct approach (using these events or do I need to set and clear some global bool that I create to bypass all these cascading events?)

Thanks,

John

Re: List control events

Diddy26-May-04 2:46

Diddy

26-May-04 2:46

Yeah i don't think you get that event if you click on an already selected item... Have you tried processing NM_CLICK as well?

How to make code block works faster?

Kolich11-May-04 2:41

Kolich

11-May-04 2:41

I have such block:

if (a > 0)
if (a > 255) b = 255;
else b = (BYTE)a;
else b = 0;

do anyone have an idea, how to make it works faster?

Thanx.

Re: How to make code block works faster?

Nitron11-May-04 2:56

Nitron

11-May-04 2:56

Not really faster, but certainly more ~~obfuscated~~ elegant: Poke tongue | ;-P

b = a > 0 ? (a > 255 ? 255 : (byte)a) : 0;

~Nitron.

ññòòïðïðB A start

Re: How to make code block works faster?

Kolich11-May-04 3:01

Kolich

11-May-04 3:01

thanx, but i need fast, not elegant Smile | :)

such construction works even slowly.

Re: How to make code block works faster?

Nitron11-May-04 3:09

Nitron

11-May-04 3:09

Try it and benchmark it. I can say nearly for certain that little block of code is nowhere near a slight resemblance of your bottleneck. (of course that is if a and b are bytes or ints as you lead me to believe) Rule number 1 of optimization: Don't do it. Rule number 2: Don't do it _yet_.^*

So... Unless a profiler is telling you your code is bottle-necking at that small comparator block, I suggest you worry more about the rest of your code and just leave what you have. Things like passing function args by value rather than by reference, useless construction and destruction of temporary objects derived from complex class heiarchies, and other such subtle things are nearly 100% of the time your bottleneck. (Save for things like disk/network IO, etc.)

^*Herb Sutter - More Exceptional C++

~Nitron.

ññòòïðïðB A start

Re: How to make code block works faster?

Kolich11-May-04 3:14

Kolich

11-May-04 3:14

This block processing takes 3/4 of all code time.

Re: How to make code block works faster?

Nitron11-May-04 3:26

Nitron

11-May-04 3:26

Kolich wrote:
This block processing takes 3/4 of all code time.

OMG | :OMG:

no way! (unless your total processing time is like 0.000012 seconds). How long is your processing time? How many elements in your matrix? Here is the disassembly for my test block:

	if (a > 0) 
00411ADE  mov         eax,dword ptr [a] 
00411AE1  cmp         dword ptr [eax],0 
00411AE4  jle         test+48h (411B08h) 
		if (a > 255) 
00411AE6  mov         eax,dword ptr [a] 
00411AE9  cmp         dword ptr [eax],0FFh 
00411AEF  jle         test+3Ch (411AFCh) 
			b = 255;
00411AF1  mov         eax,dword ptr [b] 
00411AF4  mov         dword ptr [eax],0FFh 
		else b = a;
00411AFA  jmp         test+46h (411B06h) 
00411AFC  mov         eax,dword ptr [b] 
00411AFF  mov         ecx,dword ptr [a] 
00411B02  mov         edx,dword ptr [ecx] 
00411B04  mov         dword ptr [eax],edx 
	else b = 0;
00411B06  jmp         test+51h (411B11h) 
00411B08  mov         eax,dword ptr [b] 
00411B0B  mov         dword ptr [eax],0

that's like 16 instructions! It probably takes more just to instantiate one of your matrix objects...

~Nitron.

ññòòïðïðB A start

Re: How to make code block works faster?

Kolich11-May-04 3:33

Kolich

11-May-04 3:33

basic time takes operation b=a.
its bad.

Re: How to make code block works faster?

toxcct11-May-04 4:51

toxcct

11-May-04 4:51

you find this elegant ?????????
i agree the ?: operator is elegant when you have few (less than 2) conditions, but it becomes really unreadable otherwise.
more, it uses exactly the same time as the previous post's code. what i prefer is expanding the code, but placing the { }. it doesn't eat bread and it is really more easy to debug.
one last thing. the first written code is (by my thinking quite fast). you can so let it like this :

<font style="color:blue;">if </font>(a > 0) {
    <font style="color:blue;">if </font>(a > 255) {
        b = 255;
    }
    <font style="color:blue;">else</font> {
        b = (BYTE)a;
    }
}
<font style="color:blue;">else </font>{
    b = 0;
}

TOXCCT >>> GEII power

Re: How to make code block works faster?

Nitron11-May-04 5:00

Nitron

11-May-04 5:00

Actually, it's 2 _more_ instructions than the previous code. Wink | ;)

I was really only kidding, I would never put that into production code... Suspicious | :suss:

On a side note, I see you are a same-line bracer Eek! | :eek:

the horror! I'd much rather wade through deeply obfuscated code than to subject my tender eyes to such bracing schemes... Poke tongue | ;-P

~Nitron.

ññòòïðïðB A start

Re: How to make code block works faster?

toxcct11-May-04 5:03

toxcct

11-May-04 5:03

Nitron wrote:
I see you are a same-line bracer

where, which ? what is wrong in my code ?
i don't exactly understand your sentence. could you rephrase it please ?

TOXCCT >>> GEII power

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