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hi !
I have a control derived from CWnd and I create an instance of it on a dialog.
The problem is that the control does not get the keyboard focus when I click
on it. What am I missing ?
Thanks.
PS:I work with VC 5.
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I dunno, theres alot you could have done if your control is derived from CWnd.
Maybe make sure that your control inside your dialog resource has tab stop checked?
The word of the day is legs, let's go back to my house and spread the word 
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did you create the control with enabled bit set.
I Touched Osama Bin Ladens Bushy Beard
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Hello !
I want to have a check box in front of each data in the list box that enable the user to select the datas he wants. Is this functionnality in the CListBox or do I need to subclass the control ?
Thanks
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Try to use CListCtrl instead.
In Report View it can handle check box-es on the first column automatically.
Set extented style to LVS_EX_CHECKBOXES.
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Ok, thanks 
I'll try this
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A CListBox is a list of string items.
That having said, if you want to have check box buttons instead of string items, then the best way would be to derive a new class from the CListBox and override the DrawItem member function. This function is safe to use: by selecting a certain type of return value, you can tell Windows what type of drawing you did. For example, if draw it completely yourself, then windows doesn't need to draw it anymore. If you don't want to draw a particular cell, you can let Windows do it.
Here is a CodeProject link to help you get started: Michael Dunn's article[^]
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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I would poke around the Visual C++ section under comboboxes and listboxes someone has probably already written such a control.
Cheers 
The word of the day is legs, let's go back to my house and spread the word
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hi!,
i have put a CTreeCtrl in my view class,
i create it on my View::OnCreate and insert some items in
my View::OnInitialUpdate().
i would like to handle messages when i click on treeCtrl items
but how will achieve this?
should i subclass this treeCtrl or is there another way?
what will i do for the future controls user actions.(like Buttons, Edits...)?
thanks for ur help,,,
atilla.
just listening to you...
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You can capture notification events (WM_NOTIFY) from the tree control in your parent window class's message map.
The implementation of the message map entry is as follows:
ON_NOTIFY( <notification message>, <control ID>, <member fxn> ) The above is a message-map entry in the parent window's message map which owns the tree control.
You then declare a member function member fxn that handles the notification message.
For more information about notifications and how they work, visit this link on the MSDN site.
For a list of notification messages sent by a tree control, see this site, again on the MSDN.
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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Hi !
The project I'm working on is being made with Visual Studio 6. I used to have my project on a specific location on my disk, and some weeks ago, I changed the location.
We are using CVS as the soruce control.
I have the following problem with some classes : if I try to add a new method, I get this error message :
D:\Work\sylvie\src\Utilities\JSUtility.cpp(579) : error C2039: 'applyTransformationToList' : is not a member of 'JSUtility'
c:\scripts\sylvie\src\utilities\jsutility.h(45) : see declaration of 'JSUtility'
As you can see, instead of looking at the header file of JSUtility in D:\Work\sylvie\src\Utilities, the compiler looks at c:\scripts\sylvie etc...
This is an old location. To get rid of this message, the only way I found is to do a 'rebuild all' of the project.
I tried to look in the .dsp and .dsw files if this old location was still written somewhere but didn't find anything !
Have you got an idea on what's going on and how I could solve this problem ?
Thanks for your help !
Jerome
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This information is kept in precompiler header file (.pch). Rebuild All helps because it removes this file.
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I'm not generally known as a stupid guy, but I'm really confused by this. I've been programming for 25+ years, but I've only recently tried to add C++ to my list of proficiencies, and I'm embarrassed to ask, but I'm going to anyway.
I see code that uses the . operator to reference member functions as often as I see the -> operator used for what appears to me to be the same purpose. What the heck is the difference? Can someone explain to me, without the utterly useless Microsoft technical babble, what the difference in usage is? I know it's trivial to you experts, but I have a (hopefully) temporary blind spot that is blocking me from progressing on my journey of discovery on the path of C++ enlightenment.
Please use small words appropriate to my small understanding for your reply... And, Thank you, for helping me to overcome this silly mental block. I'm usually good at spotting patterns, but this one has me stumped.
"Another day done - All targets met; all systems fully operational; all customers satisfied; all staff keen and well motivated; all pigs fed and ready to fly" - Jennie A.
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The . operator is for non-dynamic variables. The -> operator is used for pointer variables.
I think you know what a pointer is, don´t you?
"Have no fear, the saint is here!"
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well the . and the -> actually do the same thing they server the same purpose but the difference is that the '.' (dot operator) is used when are dealing with a NORMAL object while the -> operator is used for a POINTER object like check this little snippet below
class foo
{
public :
int i;
};
when making an object of this class
foo myobject;
myobject.i = 0; //this is the normal way to access the i variable
now look at this object
foo *pobject; //now this is a pointer to object
pobject->i = 1; //this is way i will be accessed
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ok
small words? you got em
// a header file
class A
{
public:
A();
~A();
void foo();
};
// a source file
int main(int, char**)
{
A a_object;
A* a_[ointer_to_the_object = new A();
a_object.foo();
a_pointer_to_the_object->foo();
return 0;
}
you see? when you deal with a pointer - you use -> operator......
debug - is my life style
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Roger Wright wrote:
see code that uses the . operator to reference member functions as often as I see the -> operator used for what appears to me to be the same purpose. What the heck is the difference?
To the best of MY understanding
The member selection operator -> is used whenever the expression before is coupled with an indirection operator *
CMyObject myObj;
myObj.Test();
CMyObject* myObj;
myObj->Test();
You can acheive the same thing using
CMyObject myObj;
(*myObj).Test();
Basically when you use -> or *. are accessing members indirectly with a pointer.
The word of the day is legs, let's go back to my house and spread the word
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Thank you for the only marginally comprehensible answer of the lot. Frankly, pointers drive me over the edge, and make me long for the resurgence of Pascal, the only language that's made any sense in the past 20 years or so. Indirection was handy in the ASM days, and I loved using it. But it seems an absurd layer of obscurity when applied to modern languages. I really hate that part of C++.
"Another day done - All targets met; all systems fully operational; all customers satisfied; all staff keen and well motivated; all pigs fed and ready to fly" - Jennie A.
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Well, perhaps I'll add my knowledge to the heap.
Consider the following: you have an object of some type. Let's name this type 'Roger', and let it have an attribute called 'Age' (No sarcasm intended !)
Now, if in your code, you created a static object, you would use Roger MyRoger declaration. This would create a static object for you. You would then access the member variable by using MyRoger.Age = 30, for example.
Let's take a step beyond and consider a pointer. See in front of yourself a 3D-space. In this space, you see the MyRoger-object standing at some point. Then, you create a pointer of type Roger using a declaration Roger* pToMyRoger = &MyRoger. Now, the pToMyRoger pointer points towards the MyRoger object, just like an extended finger.
A static object is aware of two things: what it is, and where it resides. A pointer to any object is aware of two things as well: where it resides, and what is to be found in that location.
For a more in-depth scenario, consider that your Roger-object (MyRoger) reserves a place for itself in memory (&MyRoger). If you issued MyRoger.Age, the compiler would get the address of MyRoger, move forwards from there to the Age variable, and retrieve it's contents. If you used a pointer, then the compiler would take the address you give to that pointer, and ASSUME that the object found from that address is the one specified by the type of the pointer (Roger*). It would then search for the Age variable again, and retrieve it.
Then to the term 'dereferencing'. When you have pointer to the object Roger (pToMyRoger), you can dereference it to an OBJECT of type Roger by using the asterisk (*) operator. For example, this declaration (*pToMyRoger).Age is the same thing as MyRoger.Age. As you might guess, *pToMyRoger equals to MyRoger hence leading us to the following conclusion: the dereferencing operator (*) can sometimes be named as the 'contents-of' operator. Thus, the contents of pToMyRoger (*pToMyRoger) equals to the object MyRoger (MyRoger). Does this make sense ?
In the conclusion, the '.' and the '->' operators behave similarly, but they are used in different contexts. For example, the following declarations do all the same things
MyRoger.Age = (*pToMyRoger).Age = pToMyRoger->Age = (&MyRoger)->Age
I am not sure about the final declaration, as I have never tested it. But, it should work according to the C++ language syntax, to which we will not dive right now 
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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Thanks! That helps clarify things quite a bit.
"Another day done - All targets met; all systems fully operational; all customers satisfied; all staff keen and well motivated; all pigs fed and ready to fly" - Jennie A.
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I just finished writting a bunch of verbage and an error occurd when I sent it 
And I don't think it sent...sux when that happens
Anyways...you've helped me more often then not during my times here at CP so any time I can help back i'm more then happy.
Cheers
The word of the day is legs, let's go back to my house and spread the word
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The feelings you are having towards c++ are normal and understandable for a person trying to learn the language. Once you fully grasp the concepts and advantages (as well as disadvantages) of pointers you will view them in a much different light for sure.
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I suppose so, though I haven't yet found any use for a pointer, nor any need to use one other than to comply with the declaration of some class or other.
"Another day done - All targets met; all systems fully operational; all customers satisfied; all staff keen and well motivated; all pigs fed and ready to fly" - Jennie A.
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Roger Wright wrote:
But it seems an absurd layer of obscurity when applied to modern languages. I really hate that part of C++.
Technically, pointers existed long before C++.
A rich person is not the one who has the most, but the one that needs the least.
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