C / C++ / MFC

2-Dec-05 8:51

Im looking for a good example to show me how to use a slider control. Ive some useful things through googling, but wondering if anyone knows of a good tutorial sorta thing. Some the questions im looking to get solved is, i have a vertical slider, and it increases as the thumb goes down, and i want that inveresed. The other is how to limit the interval of the thumb? I have set the range from 0 - 3000 and only want it in multiples of 50. Some others would be how to implement the VM_VSCROLL deal, im not quite sure how to do that. And on and on... Thanks in advance.
-Jader89

"There are 10 types of people, those who understand binary, and those who don't."
- Somebody, not me.

Jader892-Dec-05 8:53

2-Dec-05 8:53

Not so much graphically, but functionality

"There are 10 types of people, those who understand binary, and those who don't."
- Somebody, not me.

David Crow2-Dec-05 9:16

2-Dec-05 9:16

Jader89 wrote:
Im looking for a good example to show me how to use a slider control.

This would be a good place to start.

"Take only what you need and leave the land as you found it." - Native American Proverb

Jader892-Dec-05 9:29

2-Dec-05 9:29

I've been there, doesnt help much on what i want to do. Unless im blind and missing a blantantly obvious method, among other things.

"There are 10 types of people, those who understand binary, and those who don't."
- Somebody, not me.

David Crow2-Dec-05 9:49

2-Dec-05 9:49

You need to use the TBS_DOWNISLEFT style, although this style may just be ignored by the control.

"Take only what you need and leave the land as you found it." - Native American Proverb

Jader892-Dec-05 12:26

2-Dec-05 12:26

I've tried that and TBS_REVERSED , all combonations of both and it still seems to not be working.. Here is the part in the .rc file. Any ideas why this doesnt work?

CONTROL         "",IDC_SLIDER1,"msctls_trackbar32",TBS_AUTOTICKS|     TBS_VERT | TBS_TOP | TBS_ENABLESELRANGE | TBS_DOWNISLEFT | WS_GROUP | WS_TABSTOP | 0x400,207,23,21,116

Here is the OnInitDialog(), there is no other place i do anything with it.

BOOL CThisClass::OnInitDialog()<br />
{<br />
	BOOL ret;<br />
	ret = CDialog::OnInitDialog();<br />
<br />
	altCtrl.SetRange(0, 3000);<br />
	altCtrl.SetTicFreq(300);<br />
	altCtrl.SetPos(3000);<br />
	UpdateData(FALSE);<br />
<br />
	return ret;<br />
}

"There are 10 types of people, those who understand binary, and those who don't."
- Somebody, not me.

David Crow3-Dec-05 15:04

3-Dec-05 15:04

Jader89 wrote:
Any ideas why this doesnt work?

Yes. Like I indicated, it may be one of those styles that the control ignores. I can neither confirm nor deny this, though.

"Take only what you need and leave the land as you found it." - Native American Proverb

Function Traceback

Suvendra2-Dec-05 8:24

2-Dec-05 8:24

Hi All,

Is there a way to know the reference to the calling function at runtime without using some flag variables? For eg.

<br />
void foo() {<br />
    foobar();<br />
}<br />
<br />
void bar() {<br />
    foobar();<br />
}<br />
<br />
void foobar() {<br />
    /* What will be the condition for this IF? */<br />
    if (calling function is 'foo') {<br />
        bla... bla..<br />
    } else {<br />
        bla... bla..<br />
    }<br />
}<br />

Thanks.

David Crow2-Dec-05 8:42

2-Dec-05 8:42

The only thing I can think of it to pass an argument to the foobar() function.

"Take only what you need and leave the land as you found it." - Native American Proverb

Suvendra2-Dec-05 8:56

2-Dec-05 8:56

DavidCrow wrote:
The only thing I can think of it to pass an argument to the foobar() function.

Thanks David. But maybe I did not put my question correctly. I have a library and I want to hide a function from direct calling by functions which are external to the library. Kind of like keeping it in private: section of a C++ class. But the problem is, I want the library in pure C and not C++. So, my library function 'foo()' should be able to invoke foobar() correctly. However, if an external function bar() tries to invoke it, the library should be able to correctly identify it and return appropriate error.

Appreciate your help.

David Crow2-Dec-05 9:11

2-Dec-05 9:11

Even with these new constraints, my suggestion will still work. All you have to do is choose a number to pass to the exported foobar() function that will likely not be guessed by others.

"Take only what you need and leave the land as you found it." - Native American Proverb

Suvendra2-Dec-05 9:29

2-Dec-05 9:29

DavidCrow wrote:
Even with these new constraints, my suggestion will still work. All you have to do is choose a number to pass to the exported foobar() function that will likely not be guessed by others.

You are right. That is a Workable solution. Thanks David.

Maximilien2-Dec-05 9:19

Maximilien

2-Dec-05 9:19

I'm not certain that you can hide functions in a library; hackers will find the name and arguments for it in the library ( but I might be wrong )

If the function is not "published" in a header file, a normal user will not call it.

Maximilien Lincourt
Your Head A Splode - Strong Bad

Suvendra2-Dec-05 9:38

2-Dec-05 9:38

Maximilien wrote:
If the function is not "published" in a header file, a normal user will not call it.

I agree with you on that. Thanks Maximilien.