View source for WinCheckButton

This macro sets the checked state of the specified button control. It returns the previous check state. 

==Syntax==
WinCheckButton(hwndDlg, usId, usChkstate);

==Parameters==
;hwndDlg (HWND) - input
:Dialog window handle. 

;usId (USHORT) - input
:Button control identity. 

;usChkstate (USHORT) - input
:Indicates the current checked state of the button. 

==Returns==
;usRetChkst (USHORT) - returns
:Returns the previous checkstate.

==Remarks==
This macro expands to:

#define WinCheckButton(hwndDlg, usId, usChkstate)
  ((USHORT)WinSendDlgItemMsg(hwndDlg,
                             usId,
                             BM_SETCHECK,
                             MPFROMSHORT(usChkstate),
                             (MPARAM)NULL))

This call requires the existence of a message queue. 

==Example Code==
This example responds to a button click (BN_CLICKED, WM_CONTROL message) on a check box by setting the checked state of the button. 
<pre>
#define INCL_WINWINDOWMGR       /* Window Manager Functions     */
#define INCL_WINBUTTONS         /* Window Button definitions    */
#include <os2.h>

USHORT  usCheckId;      /* check box id                         */
HWND  hwndDlg;          /* dialog window handle                 */
USHORT  usChkstate;     /* new checked state                    */
USHORT  usOldstate;     /* old checked state                    */
MPARAM  mp1;            /* Parameter 1 (rectl structure)        */
MPARAM  mp2;            /* Parameter 2 (frame boolean)          */

case WM_CONTROL:
     /* switch on control code */
     switch(SHORT2FROMMP(mp1))
        {
        case BN_CLICKED:
             usCheckId = SHORT1FROMMP(mp1);

             /* query current check state */
             usChkstate = WinQueryButtonCheckstate(hwndDlg,
                          usCheckId);

             /* set box check state */
             usOldstate = WinCheckButton(hwndDlg, usCheckId,
                                         usChkstate);
             break;
        }


</pre>

Definition
<pre>
#define INCL_WINWINDOWMGR /* Or use INCL_WIN, INCL_PM, */
#include <os2.h>

HWND      hwndDlg;     /*  Dialog window handle. */
USHORT    usId;        /*  Button control identity. */
USHORT    usChkstate;  /*  Indicates the current checked state of the button. */
USHORT    usRetChkst;  /*  Returns the previous checkstate. */

usRetChkst = WinCheckButton(hwndDlg, usId,
               usChkstate);
</pre>

==Related Functions==
* [[WinSendDlgItemMsg]]

==Related Messages==
* BM_SETCHECK 

[[Category:Win]]