//-----------------------------------------------------------------------------
// Defines

#define WIN32_LEAN_AND_MEAN // MFC wird nicht benoetigt

//-----------------------------------------------------------------------------
// Header

#include <windows.h>
#include <TCHAR.h>

//-----------------------------------------------------------------------------
// Event Handler
LRESULT CALLBACK WindowProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
{
	switch(msg)
	{
		case WM_DESTROY:
			PostQuitMessage(0);
			return 0;

		default: break;
	}

	return (DefWindowProc(hwnd, msg, wparam, lparam));
}

//-----------------------------------------------------------------------------
// Main
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdline, int nCmdShow)
{
	WNDCLASSEX winclass;
	winclass.cbSize = sizeof(WNDCLASSEX);
	winclass.style = CS_VREDRAW | CS_HREDRAW | CS_OWNDC | CS_DBLCLKS;
	winclass.lpfnWndProc = WindowProc;
	winclass.cbClsExtra = 0; // extra class info space
	winclass.cbWndExtra = 0; // extra window info space
	winclass.hInstance = hInstance; // assign the application instance
	winclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
	winclass.hCursor = LoadCursor(NULL, IDC_ARROW);
	winclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	winclass.lpszMenuName = NULL; // the name of the menu to attach
	winclass.lpszClassName = __T("WINCLASS1"); // the name of the class itself
	winclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);

	RegisterClassEx(&winclass);
	HWND hwnd;
	hwnd = CreateWindowEx(	NULL,
							__T("WINCLASS1"),
							__T("Fenstertitel"),
							WS_OVERLAPPEDWINDOW | WS_VISIBLE,
							0,
							0,
							200,
							200,
							NULL, // handle to parent
							NULL, // handle to menu
							hInstance, // instance of this application
							NULL);

	if(hwnd==NULL)
		return -10;

	// create a second window
	HWND hwnd2;
	hwnd2 = CreateWindowEx(	NULL,
							__T("WINCLASS1"),
							__T("Fenster 2"),
							WS_OVERLAPPEDWINDOW | WS_VISIBLE,
							0,
							0,
							300,
							300,
							NULL, // handle to parent
							NULL, // handle to menu
							hInstance, // instance of this application
							NULL);

	if(hwnd2==NULL)
		return -11;

	UpdateWindow(hwnd2);
	ShowWindow(hwnd2, 0);

	MSG msg;
	while(GetMessage(&msg, NULL, 0, 0))
	{
		// translate any accelerator keys
		TranslateMessage(&msg);
		// send the message to the window proc
		DispatchMessage(&msg);
	}
	return 0;
}

unteranderem weil du net ShowWindow(hwnd); aufrufst... du sagst nur das der ShowWindow(hwnd2); machen soll -.- und anders

Nein, das ist es nicht, da er ja bei beiden WS_VISIBLE als Style übergibt, dann ist das ShowWindow(hwnd); nicht mehr erforferlich.

mfg.

UpdateWindow(hwnd2);
ShowWindow(hwnd2, 0);

dann funktiniert es. Ich hab aber keine Ahnung warum...

also:

//-----------------------------------------------------------------------------
// Defines

#define WIN32_LEAN_AND_MEAN // MFC wird nicht benoetigt

//-----------------------------------------------------------------------------
// Header

#include <windows.h>
#include <TCHAR.h>

//-----------------------------------------------------------------------------
// Event Handler
LRESULT CALLBACK WindowProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
{
    switch(msg)
    {
        case WM_DESTROY:
            PostQuitMessage(0);
            return 0;

        default: break;
    }

    return (DefWindowProc(hwnd, msg, wparam, lparam));
}

//-----------------------------------------------------------------------------
// Main
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdline, int nCmdShow)
{
    WNDCLASSEX winclass;
    winclass.cbSize = sizeof(WNDCLASSEX);
    winclass.style = CS_VREDRAW | CS_HREDRAW | CS_OWNDC | CS_DBLCLKS;
    winclass.lpfnWndProc = WindowProc;
    winclass.cbClsExtra = 0; // extra class info space
    winclass.cbWndExtra = 0; // extra window info space
    winclass.hInstance = hInstance; // assign the application instance
    winclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    winclass.hCursor = LoadCursor(NULL, IDC_ARROW);
    winclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    winclass.lpszMenuName = NULL; // the name of the menu to attach
    winclass.lpszClassName = __T("WINCLASS1"); // the name of the class itself
    winclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);

    RegisterClassEx(&winclass);
    HWND hwnd;
    hwnd = CreateWindowEx(    NULL,
                            __T("WINCLASS1"),
                            __T("Fenstertitel"),
                            WS_OVERLAPPEDWINDOW | WS_VISIBLE,
                            0,
                            0,
                            200,
                            200,
                            NULL, // handle to parent
                            NULL, // handle to menu
                            hInstance, // instance of this application
                            NULL);

    if(hwnd==NULL)
        return -10;

    // create a second window
    HWND hwnd2;
    hwnd2 = CreateWindowEx(    NULL,
                            __T("WINCLASS1"),
                            __T("Fenster 2"),
                            WS_OVERLAPPEDWINDOW | WS_VISIBLE,
                            0,
                            0,
                            300,
                            300,
                            NULL, // handle to parent
                            NULL, // handle to menu
                            hInstance, // instance of this application
                            NULL);

    if(hwnd2==NULL)
        return -11;

   // UpdateWindow(hwnd2);
    //ShowWindow(hwnd2, 0);

    MSG msg;
    while(GetMessage(&msg, NULL, 0, 0))
    {
        // translate any accelerator keys
        TranslateMessage(&msg);
        // send the message to the window proc
        DispatchMessage(&msg);
    }
    return 0;
}

ShowWindow(hwnd2, 0 );

ist gleichbedeutend mit

ShowWindow(hwnd2, SW_HIDE );