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[WIN32 API] Multiple Window Creation.

CGunn86 (168)
Messing with the WINAPI and trying to get 2 separate windows to load in the event I ever create a GUI app where say a menu item might load up another window (options window or something).

Anyways I'm having trouble getting a second window on screen. Loads the first window just fine. Any clues as to why would be greatly appreciated.

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#include <Windows.h>
#include "globals.h"

LPCTSTR clsName = "First Class Name";
LPCTSTR wndName = "First Window";
LPCTSTR clsName2 = "Second Class Name";
LPCSTR wndName2 = "Second Window";

LRESULT CALLBACK wndProc2(HWND hWnd2, UINT Msg, WPARAM wParam, LPARAM lParam)
{
	LRESULT Result = 0;

	switch (Msg)
	{
	case WM_CREATE:
		break;

	case WM_CLOSE:
		break;

	case WM_DESTROY:
		break;

	default:
		Result = DefWindowProc(hWnd2, Msg, wParam, lParam);
	}

	return(Result);
}

LRESULT CALLBACK wndProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam)
{
	LRESULT Result = 0;

	switch (Msg)
	{
		case WM_CREATE:
			break;

		case WM_COMMAND:
		{
			switch (LOWORD(wParam))
			{
				case ID_FILE_EXIT:
				{
					PostQuitMessage(0);
				} break;

				case ID_TOOLS_OPTIONS:
				{
					MessageBox(NULL, "Options will be here", "Options", MB_OK | MB_ICONINFORMATION);
				} break;

				case ID_HELP_ABOUT:
				{
					MessageBox(NULL, "About information will be here", "About", MB_OK | MB_ICONINFORMATION);
				} break;

			} break;
		}

		case WM_CLOSE:
		{
			PostQuitMessage(0);
		} break;

		case WM_DESTROY:
		{
			DestroyWindow(hWnd);
		} break;

		case WM_PAINT:
		{
			PAINTSTRUCT Paint;
			HDC DeviceContext = BeginPaint(hWnd, &Paint);
				int X = Paint.rcPaint.left;
				int Y = Paint.rcPaint.top;
				int Width = Paint.rcPaint.right - Paint.rcPaint.left;
				int Height = Paint.rcPaint.bottom - Paint.rcPaint.top;
				PatBlt(DeviceContext, X, Y, Width, Height, WHITENESS);
			EndPaint(hWnd, &Paint);
		}

		default:
		{
			Result = DefWindowProc(hWnd, Msg, wParam, lParam);
		}
	}

	return(Result);
}

int CALLBACK WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
	MSG Msg;
	HWND hWnd;
	HWND hWnd2;
	WNDCLASS wc = { 0 };
	WNDCLASS wc2 = { 0 };

	ZeroMemory(&hWnd, sizeof(hWnd));

	//First Window Class
	wc.hInstance = hInstance;
	wc.lpfnWndProc = wndProc;
	wc.lpszClassName = clsName;
	wc.lpszMenuName = IDR_MAINMENU;
	wc.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;

	//Second Window Class
	wc2.hInstance = hInstance;
	wc2.lpfnWndProc = wndProc2;
	wc2.lpszClassName = clsName;
	wc2.lpszMenuName = IDR_MAINMENU;
	wc2.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;

	if (!RegisterClass(&wc) && !RegisterClass(&wc2))
	{
		MessageBox(NULL, L"Error Registering Class", L"ERROR", MB_OK | MB_ICONERROR);
	}

	hWnd2 = CreateWindow(clsName2, wndName2, WS_OVERLAPPEDWINDOW ^ WS_THICKFRAME | WS_VISIBLE, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);
	hWnd = CreateWindow(clsName, wndName, WS_OVERLAPPEDWINDOW ^ WS_THICKFRAME | WS_VISIBLE, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);
	if (!hWnd)
	{
		MessageBox(NULL, L"Error Creating Window", L"Error", MB_OK | MB_ICONERROR);
	}

	ShowWindow(hWnd2, nCmdShow);
	UpdateWindow(hWnd2);
	ShowWindow(hWnd, nCmdShow);
	UpdateWindow(hWnd);

	while (GetMessage(&Msg, 0, 0, 0))
	{
		TranslateMessage(&Msg);
		DispatchMessage(&Msg);
	}

	return Msg.wParam;
}
freddie1 (1838)
I've covered that topic quite exhaustively at these links...

http://www.jose.it-berater.org/smfforum/index.php?topic=3390.0

http://www.jose.it-berater.org/smfforum/index.php?topic=3392.0

At the top link are examples of creating multiple instances of the same Window Class - and keeping instance data seperate.

At the 2nd link (reply #5!) is an example of a main start up Window Class, which launches windows of seperate but different Window Classes, which I think is what you are trying to do.

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