Visual C++ 6.0 Sliders in Dialog Boxes

I have created a dialog box that has a checkbox and want to put a slider in it as well. I don't know how to get information from the slider I have put into the dialog box and I don't know how to set the ticks on the slider. I have the checkbox working correctly and use the following functions to get the information from it:

::CheckDlgButton
::IsDlgButtonChecked

What functions would I use to get information from the slider? And how can I set the slider's ticks?

If using Win32 API - Trackbar Controls
If using MFC - Using CSliderCtrl

gg

Ok, I tried putting the Win32 API function in my code and I get the following problems:

1. it says 'hwndTrack' is an undeclared identifier
2. I can't figure out what I'm supposed to put for the instance (where it has g_hinst in the example)

How can I get this function to work?

Well, the examples aren't always meant to be a copy-and-paste solution, but this one is fairly close.

'hwndTrack' should be a local var so just declare it locally with "HWND hwndTrack;".
'g_inst' represents your module's HINSTANCE to be associated with the window. If your module is an EXE (and not a DLL) then you can use the value passed to WinMain() or use the return value of GetModuleHandle(NULL).

gg

Ok, I fixed the hwndTrack error, but I still can't figure out the instance. How would I find the HINSTANCE associated with my dialog window?

Originally Posted by Codeplug

'g_inst' represents your module's HINSTANCE to be associated with the window. If your module is an EXE (and not a DLL) then you can use the value passed to WinMain() or use the return value of GetModuleHandle(NULL).

gg

Use one or the other. The return value from GetModuleHandle(NULL) can be used as an HINSTANCE.

gg

Originally Posted by The Letter J

How would I find the HINSTANCE associated with my dialog window?

Originally Posted by Codeplug

use the return value of GetModuleHandle(NULL).

.....

My program is a simple dll, so I used GetModuleHandle(NULL) and got the following error:

cannot convert parameter 10 from 'const int' to 'struct HMENU__ *'

Here is how I put it in:

Code:

hwndTrack = CreateWindowEx( 
        0,                             // no extended styles 
        TRACKBAR_CLASS,                // class name 
        "Trackbar Control",            // title (caption) 
        WS_CHILD | WS_VISIBLE | 
        TBS_AUTOTICKS | TBS_ENABLESELRANGE,  // style 
        10, 10,                        // position 
        200, 30,                       // size 
        gOptionsDlg,                       // parent window 
        IDC_SLIDER1,             // control identifier 
        GetModuleHandle(NULL),                       // instance 
        NULL                           // no WM_CREATE parameter 
        );

Would it help to know that I used the dialog boxes in the resource creator in VC++ 6.0 as opposed to coding it in raw C++?

Staticly cast GetModuleHandle(NULL) to HMENU:

(HMENU)GetModuleHandle(NULL)

Ok, I did that and got the following error:

'CreateWindowExA' : cannot convert parameter 10 from 'const int' to 'struct HMENU__ *'
Conversion from integral type to pointer type requires reinterpret_cast, C-style cast or function-style cast

Here is how I put it in:

Code:

hwndTrack = CreateWindowEx( 
        0,                             // no extended styles 
        TRACKBAR_CLASS,                // class name 
        "Trackbar Control",            // title (caption) 
        WS_CHILD | WS_VISIBLE | 
        TBS_AUTOTICKS | TBS_ENABLESELRANGE,  // style 
        10, 10,                        // position 
        200, 30,                       // size 
        gOptionsDlg,                       // parent window 
        IDC_SLIDER1,             // control identifier 
        (HMENU)GetModuleHandle(NULL),                       // instance 
        NULL                           // no WM_CREATE parameter 
        );

You need to cast the control identifier (which, incidentally, is parameter 10):

Code:

hwndTrack = CreateWindowEx( 
        0,                             // no extended styles 
        TRACKBAR_CLASS,                // class name 
        "Trackbar Control",            // title (caption) 
        WS_CHILD | WS_VISIBLE | 
        TBS_AUTOTICKS | TBS_ENABLESELRANGE,  // style 
        10, 10,                        // position 
        200, 30,                       // size 
        gOptionsDlg,                       // parent window 
        (HMENU) IDC_SLIDER1,             // control identifier 
        GetModuleHandle(NULL),                       // instance 
        NULL                           // no WM_CREATE parameter 
        );

GetModuleHandle(NULL) will give you the handle of the process or exe, not the current DLL. This was mentioned by Codeplug:

Originally Posted by Codeplug

'g_inst' represents your module's HINSTANCE to be associated with the window. If your module is an EXE (and not a DLL) then you can use the value passed to WinMain() or use the return value of GetModuleHandle(NULL).

If you need the handle of a DLL, you should store it in DllMain, or use another method. However, on NT/2000/XP the hInstance argument of CreateWindowEx is ignored, so your program may still work.

Hello,

If you view this reference you will see that parameter 10 is HMENU and 11 is HINSTANCE. Don't cast the 11th parameter as HMENU, rather cast the 10th.

If you aren't using a resource, define the variable right after including header files and/or put this code in your own header file. For instance:

Code:

#define IDC_SLIDER1 10

This defines IDC_SLIDER1. For a child window, hMenu specifies the child-window identifier, an integer value used by a dialog box control to notify its parent about events.


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Ok, I fixed that part, but I am now getting 2 completely new errors:

error LNK2001: unresolved external symbol __imp__InitCommonControls@0
fatal error LNK1120: 1 unresolved externals

I have no idea what either of these two mean, can anyone help me out? This is really starting to get frustrating.

Hello,

You aren't linking to comctl32.lib which this API is defined in. This library is not included by default so you will either need to add it to the libraries on your command line, or add it in your VC++ project settings on the Link tab.

You can add it in the source code by doing the following:

Code:

#include <commctrl.h>			// Include header

#pragma comment(lib, "comctl32.lib")	// Include library

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