CheckBox Dialog

The complete message flow for a checkbox in a Win32 dialog: the control fires WM_COMMAND with its own ID when clicked, and IsDlgButtonChecked tells you whether it landed checked or unchecked. The surrounding template also shows the standard system-menu extras (a separator plus custom items handled in WM_SYSCOMMAND) and an About sub-dialog. Use it as the reference whenever you need reliable check-state detection without owner-draw tricks.

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#include <Windows.H>
#include <WindowsX.H>
#include <ShellAPI.H>
#include <Stdio.H>
#include <Stdlib.H>

#include "Headers/Definitions.H"
#include "Headers/Functions.H"
#include "Dialogs/MainDialog.H"
#include "Dialogs/AboutDialog.H"

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int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevious, LPSTR CmdLine, int CmdShow)
{
	HANDLE xMutex;

	if( (xMutex = OpenMutex(SYNCHRONIZE, FALSE, TitleCaption)) )
	{
		MessageBox (NULL, "Only One Instance Can Run At A Time!" , TitleCaption, 0 + MB_ICONASTERISK + MB_SYSTEMMODAL);
		ReleaseMutex(xMutex);
		CloseHandle(xMutex);
		return 1;
	}
	xMutex = CreateMutex(0, 0, TitleCaption);

	MainInstance = hInstance;

	DialogBox(MainInstance,MAKEINTRESOURCE(100),0,MainDialog);

	ReleaseMutex(xMutex);
	CloseHandle(xMutex);

	return 0;
}

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BOOL CALLBACK MainDialog(HWND hDlg, UINT Msg, WPARAM wParam, LPARAM lParam)
{
	static HMENU SystemMenu;

	while(1) // Loop Forever
	{
		if(Msg==WM_INITDIALOG)
		{
			MainDialog_hWnd=hDlg;

			SystemMenu = GetSystemMenu(MainDialog_hWnd,FALSE);
			AppendMenu(SystemMenu,MF_SEPARATOR,0,0);
			AppendMenu(SystemMenu,MF_STRING,1000,"www.NetWorkDLS.Com");
			AppendMenu(SystemMenu,MF_STRING,1001,"Version");

			SendMessage(MainDialog_hWnd,(UINT)WM_SETTEXT,(WPARAM)0,(LPARAM)TitleCaption);
			SendMessage(MainDialog_hWnd,WM_SETICON,TRUE,(LPARAM)LoadIcon(GetWindowInstance(MainDialog_hWnd),MAKEINTRESOURCE(300)));

			CenterWindow(MainDialog_hWnd);
			break;
		}

		if(Msg==WM_COMMAND)
		{
			if(wParam==100) //- Okay (Dialog Command)
			{
				EndDialog(MainDialog_hWnd,0);
			}


			if(wParam==1000) //- Check Bix (Dialog Command)
			{
				if(IsDlgButtonChecked(MainDialog_hWnd,1000))
					MessageBox(MainDialog_hWnd, "Box Checked", TitleCaption, 0 + MB_ICONASTERISK + MB_TASKMODAL);
			}

			if(wParam==1500) //- About (Dialog Command)
			{
				ShowWindow(MainDialog_hWnd, SW_HIDE);
				DialogBox(MainInstance,MAKEINTRESOURCE(1000),MainDialog_hWnd,AboutDialog);
				ShowWindow(MainDialog_hWnd, SW_SHOW);
			}

			if(wParam==2000) //- Exit (Dialog Command)
			{
				EndDialog(MainDialog_hWnd,0);
			}
			break;
		}

		if(Msg==WM_SYSCOMMAND)
		{
			if(LOWORD(wParam)==1000) //- NetWorkDLS.Com (SysMenu Command)
			{
				ShellExecute(0,"Open","Http://www.NetWorkDLS.com",NULL,NULL,SW_SHOWNORMAL);
			}
			if(LOWORD(wParam) == 1001) //- Version (SysMenu Command)
			{
				MessageBox(MainDialog_hWnd, FileVersion, TitleCaption, 0 + MB_ICONASTERISK + MB_TASKMODAL);
			}
		}

		if(Msg==WM_CLOSE) //Exit (Windows Message)
		{
			KillTimer(MainDialog_hWnd,0);
			EndDialog(MainDialog_hWnd,0);
		}

		break;
	}
	return 0;
}

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