C / C++ / MFC Discussion Boards

Tom Archer4-May-02 5:23

4-May-02 5:23

While many of us know the solution, it would be great if you could share your solution as well. That way, another person searching for this will find a complete solution. Besides, you might have come up with a unique way of completing the task that would teach us all.

Cheers,
Tom Archer
Author, Inside C#
Author, Visual C++.NET Bible

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the af

Sure, this is what worked for me.

generic_user_id6-May-02 6:20

generic_user_id

6-May-02 6:20

HBRUSH hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
	
CBitmap bitmap;
CBrush brush;

bitmap.LoadBitmap(IDB_BACKG);
	
int nCtrl = pWnd->GetDlgCtrlID();
pDC->SetBkColor(RGB_VALUE);

if ( NULL != brush.m_hObject )            
        ::DeleteObject(brush);        

brush.CreatePatternBrush(&bitmap);
hbr = brush;
return hbr;

This is not written by me though, I read something like this somewhere else.

Re: Sure, this is what worked for me.

Tom Archer6-May-02 14:17

Tom Archer

6-May-02 14:17

Um...what does this have to do with getting the children of a HTREEITEM Smile | :)

Cheers,
Tom Archer
Author - Inside C#, Visual C++.NET Bible

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the af

Re: Sure, this is what worked for me.

generic_user_id6-May-02 23:24

generic_user_id

6-May-02 23:24

Oops, I answered the wrong question of myself here. Smile | :)

My solution to this one was pretty cheap, I just made a counter (structure with HTREEITEM and an INT) and every time an item was added to a part of a tree I updated the counter.

As the user could not add or delete things from the tree, this solution worked quite well.

I used GetItemtext(..), added "(%d)" to the string and set the new string with SetItem(..)

But I take it this was not the 'obvious' solution Smile | :)

Event handling for dynamically created controls

sanskypotov3-May-02 23:48

sanskypotov

3-May-02 23:48

Hi,
I am having the following scenario
a class CMy( and is not MFC class ),
and I create 3 objects a,b,c ( actually I need to create
any number of objects)

CMy a , b ,c

now CMy has an event WM_LBUTTONDOWN, WM_LBUTTONUP

I want only 1 function(event handler) OnMouseLButtonDown(),
so this is called whenever I press any one of the object
i.e a , b or c

I am trying to avoid Subclassing.

Can some tell me what should I do.
Thanks,
Sansky Big Grin | :-D

God is Good, all the Time.
All the Time, God is Good.

Re: Event handling for dynamically created controls

Maxwell Chen4-May-02 0:13

Maxwell Chen

4-May-02 0:13

Maybe you may try to modify my code below into what you want to...

#include <iostreamᡊe9ac73-238b-46be-991d-0f050c37248dusing namespace std;

class CCore
{
public:
	void Job(int iId) {
		// Do the job
		cout << "Hey this is button " << iId << " clicked.\n";
		// Passing info from that ID to WM_LBUTTONDOWN....
	}
};

class CMy
{
	int _iId;
	static CCore _EventMachine;

public:
	CMy(int iId) { _iId = iId; }
	void ButtonLClicked() {
		_EventMachine.Job(_iId);
	}
};

CCore CMy::_EventMachine;


void main()
{
	CMy	btn[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};

	btn[2].ButtonLClicked();
	btn[6].ButtonLClicked();
}

Maxwell Chen
People say "No news is good news". Then, no code is good code!?

Re: Event handling for dynamically created controls

Tom Archer4-May-02 5:44

Tom Archer

4-May-02 5:44

Subclassing is precisely what you need. In fact, it's what the MFC control classes do for you internally. Therefore, you don't want to use MFC, you'll need to either manually do the subclassing yourself or use another library that does it (such as MFC).

Cheers,
Tom Archer
Author, Inside C#
Author, Visual C++.NET Bible

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the af

Re: Event handling for dynamically created controls

Maxwell Chen4-May-02 7:40

Maxwell Chen

4-May-02 7:40

Tom Archer wrote:
Subclassing is precisely what you need.

Hi Tom, was my way wrong ?
Confused | :confused:

Maxwell Chen
People say "No news is good news". Then, no code is good code!?

Re: Event handling for dynamically created controls

Neville Franks4-May-02 11:17

Neville Franks

4-May-02 11:17

Hi Maxwell, I would have thought you would have a base class as you've done and then have virtual OnxxxButton() function in the base class to handle the event. This could then be overriden in the derived classes as required.

Neville Franks, Author of ED for Windows. www.getsoft.com

Re: Event handling for dynamically created controls

Tom Archer4-May-02 11:21

Tom Archer

4-May-02 11:21

Hi Maxwell,

I guess I'm just not understanding how your code is going to attach handlers to control windows messages without hooking the control's wndproc. Can you explain that a bit more? Maybe I'm just missing something obvious here.

Cheers,
Tom Archer
Author, Inside C#
Author, Visual C++.NET Bible

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the af

Re: Event handling for dynamically created controls

Tom Archer4-May-02 12:52

Tom Archer

4-May-02 12:52

Ok. I finally took more than a second to look at your code Smile | :)

The issue is that I'm looking at it from a different level than you. You're assuming you already have the routed messages (via subclassing the control) and are providing an event machine to better handle the messaging of an array of controls. I, on the other hand, was thinking that the poster wasn't even at the point of getting the messages for the controls yet. He hasn't responded to any of the posts yet so it'll be interesting to see what he really is trying to get.

By the way, with regards to your "event engine", is this something you threw together for this question or is it something more fleshed out that you could share with us (maybe in an article with examples of its use)?

Cheers,
Tom Archer
Author, Inside C#
Author, Visual C++.NET Bible

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the af

Re: Event handling for dynamically created controls

Maxwell Chen4-May-02 21:23

Maxwell Chen

4-May-02 21:23

CMy is non-MFC ? Ok., forget it, I might be wrong......

Maxwell Chen
People say "No news is good news". Then, no code is good code!?

Re: Event handling for dynamically created controls

Tom Archer5-May-02 4:31

Tom Archer

5-May-02 4:31

Exactly. He wants a non-MFC solution, which was my first question as to how you were getting the messages to begin with. Your solution looks quite intriguing, but assumes that the messages are already being received in some fashion.

Cheers,
Tom Archer
Author, Inside C#
Author, Visual C++.NET Bible

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the af

Re: Event handling for dynamically created controls

sanskypotov6-May-02 9:11

sanskypotov

6-May-02 9:11

Hi ,
Thanks for the reply.
I certainly have limitations here. I am trying to create
instances of 3rd party Ax( ActiveX ), and hence I am not
able to SubClass it.
Secondly I tried using ON_EVENT_RANGE, but here I don't
know how to detect the Control ID .
Can someone shed more light on this.
Thanks,
Sansky Big Grin | :-D

God is Good, all the Time.
All the Time, God is Good.

Where Can i find a source code of TabCtrlBar?

xsword3-May-02 19:36

xsword

3-May-02 19:36

Where Can i find a source code of TabCtrlBar?

i am coming quietly just as i am leaving quietly.

owner-draw popup menu

Gabriel.P.G3-May-02 17:51

Gabriel.P.G

3-May-02 17:51

Hi, i have an owner draw popup menu that always return 0, as if no command was selected. i´m using the TPM_RETURN_CMD flag, and GetLastError also returns 0. So i don´t know where the error can be! If i don´t use the flag the command handlers never get called either.
There is nothing about owner-draw menu´s command notifications on the sdk docs.
I´m not using mfc or wtl just plain sdk ( wanna learn )

Any idea??'

Gabriel

don´t worry drink happy

Debug error

Stan the man3-May-02 16:57

Stan the man

3-May-02 16:57

I am having a real tough time figuring out where the following is coming from:

The instruction at ... referenced memory at ... The memory could not be read.

THe problem is that the program works fine while I do thing back and forth. What I mean is the same "motion" many times. SOmtimes I close it and open it again. Then this occassionally comes up. What exactly causes this? Is it mainly when you use new ? If you use Cstring etc that should not occur right?

Because this does not happen all the time or at so .. intervals it is so tough to track down.

Thanks for any suggestions.

Re: Debug error

C^hris L^osinger3-May-02 18:32

C^hris L^osinger

3-May-02 18:32

it usually means you have a stray pointer somewhere (possibly as a result of using "new")

-c

I don't care, and you can't make me.

Smaller Animals Software

Re: Debug error

l a u r e n3-May-02 23:28

l a u r e n

3-May-02 23:28

intermittent bugs like this usually mean you have a path thru the code that gets executed very rarely ... check all code paths and the new and deletes

bummer
Hmmm | :|

situations to avoid #37:
"good morning ... how many sugars do you take in your coffee ... and what was your name again?"

coming soon: situations to avoid #38: "...and the dog was there too?"

Re: Debug error

Stan the man4-May-02 7:08

Stan the man

4-May-02 7:08

Thanks. I think I found the little beast.

Capture the screen (GDI)

Nish Nishant3-May-02 14:58

Nish Nishant

3-May-02 14:58

Hello,

I'd like to know the simplest way by which I can capture the entire screen [I dont want that method where we send a Print-Screen-Key and get it in the clipboard]

Can someone give me some elementary steps. Code not needed unless necessary.

Something like

1. get the DC
2. stretch blt it or whatever
3. now get some oher dc
etc...

My GDI sucks! So pardon the absolute stupidity that this post might seem to reflect in the above 3 lines Smile | :)

Nish

Check out last week's Code Project posting stats presentation from :-
http://www.busterboy.org/codeproject/
Feel free to make your comments.

Re: Capture the screen (GDI)

Shog⁹3-May-02 16:31

Shog⁹

3-May-02 16:31

I haven't tried this, so it may not work, but it sounds plausible Smile | :)

:

Get the screen DC ( ::GetDC(NULL) )
Get the size of the screen ( ::GetDeviceCaps(HORZRES); ::GetDeviceCaps(VERTRES); )
Create a compatible memory DC (i'm tired of typing <code> and you said it wasn't required Poke tongue | ;-P

)
Create a compatible bitmap of the same size
Select the bitmap in the memory DC
Blit from the screen DC to the memory DC

--------
People they come together
People they fall apart.
No one can stop us now
'cause we are all made of stars...

-- Moby, We are all made of stars

Re: Capture the screen (GDI)

Nish Nishant3-May-02 16:35

Nish Nishant

3-May-02 16:35

Thanks Shog Smile | :)

Nish

Check out last week's Code Project posting stats presentation from :-
http://www.busterboy.org/codeproject/
Feel free to make your comments.

Re: Capture the screen (GDI)

Tom Archer3-May-02 20:47

Tom Archer

3-May-02 20:47

I did this as a demo for one of the chapters in my MFC book. If you want I'll send you the source code.

Cheers,
Tom Archer
Author, Inside C#

A total abstainer is one who abstains from everything but abstention, and especially from inactivity in the affairs of others.

Re: Capture the screen (GDI)

Nish Nishant3-May-02 20:53

Nish Nishant

3-May-02 20:53

Thanks Tom. I'd love it if you could mail it to me Smile | :)

Nish

Check out last week's Code Project posting stats presentation from :-
http://www.busterboy.org/codeproject/
Feel free to make your comments.

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