Ich bin daran, eine DLL zu schreiben. Nun bin ich auf ein Problem gestossen. Ich will die Farbe des Fensters durch eine Funktion ändern.

Hier ist der Code meiner DLL:

// Dark3DCubeEnginedll.h
//
// Definitions of the functions
//
#ifndef DARK_HPP
#define DARK_HPP

#include <windows.h>
#include "Structures.h"
#include "Enumerations.h"
#include "Definitions.h"

// create a namespace, called DCE
//
namespace DCE
{
	// Create a class, called Dark3DCubeEngine
	//
	class Dark3DCubeEngine
	{
	public:

		static __declspec(dllexport) void Initialize (DCE::Dark3DCubeEngineProperties & props);
		static __declspec(dllexport) void SetWindowProperties (const int WindowWidth, const int WindowHeight,
															   const int WindowDepth);
		static __declspec(dllexport) void SetWindowColor (int R, int G, int B);
		static __declspec(dllexport) HWND OpenWindow (HINSTANCE hInstance);
		static __declspec(dllexport) LRESULT WINAPI MsgProc (HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);

	private:

		static int m_WindowWidth;
		static int m_WindowHeight;
		static int m_WindowDepth;
		static int m_R;
		static int m_G;
		static int m_B;

	}; // End of the class

} // End of the namespace

#endif

// Dark3DCubeEnginedll.cpp
//
// Definitions of the functions
//
#include "Dark3DCubeEnginedll.h"

// Create a namespace, called DCE
//
namespace DCE
{
	Dark3DCubeEngineProperties * props = new Dark3DCubeEngineProperties();
	int Dark3DCubeEngine::m_WindowDepth;  // = 0
	int Dark3DCubeEngine::m_WindowHeight; // = 0
	int Dark3DCubeEngine::m_WindowWidth;  // = 0
	int Dark3DCubeEngine::m_R;			  // = 0
	int Dark3DCubeEngine::m_G;			  // = 0
	int Dark3DCubeEngine::m_B;			  // = 0

	void Dark3DCubeEngine::Initialize(DCE::Dark3DCubeEngineProperties & props)
	{
		props.WindowWidth = m_WindowWidth;
		props.WindowHeight = m_WindowHeight;
		props.WindowDepth = m_WindowDepth;
	}

	void Dark3DCubeEngine::SetWindowProperties(const int WindowWidth, const int WindowHeight,
											   const int WindowDepth)
	{
		m_WindowWidth = WindowWidth;
		m_WindowHeight = WindowHeight;
		m_WindowDepth = WindowDepth;
	}

	void Dark3DCubeEngine::SetWindowColor(int R, int G, int B)
	{
		m_R = R;
		m_G = G;
		m_B = B;
	}

	HWND Dark3DCubeEngine::OpenWindow(HINSTANCE hInstance)
	{
		WNDCLASSEX wc;

		wc.style			= CS_HREDRAW | CS_VREDRAW;
		wc.cbSize			= sizeof (wc);
		wc.lpfnWndProc		= MsgProc;
		wc.cbClsExtra		= 0;
		wc.cbWndExtra		= 0;
		wc.hInstance		= hInstance;
		wc.hIcon			= LoadIcon (NULL, IDI_APPLICATION);
		wc.hCursor			= LoadCursor (NULL, IDC_ARROW);
		wc.hbrBackground	= (HBRUSH)CreateSolidBrush(RGB(m_R, m_G, m_B));
		wc.lpszMenuName		= NULL;
		wc.lpszClassName	= TEXT ("Dark3DCubeEngine");
		wc.hIconSm			= LoadIcon (NULL, IDI_APPLICATION);

		if (RegisterClassEx (&wc) == 0) return 0;

		return CreateWindowEx (NULL, TEXT("Dark3DCubeEngine"), "Dark3DCubeEngine",
							   WS_OVERLAPPEDWINDOW | WS_VISIBLE,
							   GetSystemMetrics(SM_CXSCREEN)/2 - 250,
							   GetSystemMetrics(SM_CYSCREEN)/2 - 187,
							   m_WindowWidth, m_WindowHeight, NULL,
							   NULL, hInstance, NULL);
	}

	LRESULT WINAPI Dark3DCubeEngine::MsgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
	{
		switch (msg)
		{
			// key was pressed
			//
		case WM_KEYDOWN:
			{
				switch (wParam)
				{
				case VK_ESCAPE:
					{
						PostMessage (hwnd, WM_CLOSE, 0, 0);
						return 0;
					} break;
				default: break;
				}
			} break;

		case WM_DESTROY:
			{
				PostQuitMessage (0);
				return 0;
			}
		default: break;
		}

		return DefWindowProc(hwnd, msg, wParam, lParam);
	}
} // End of the namespace

Doch wenn ich nun eine Farbe bei der .exe mit der Funktion SetWindowColor angebe, kommt immer nur ein schwarzes Fenster heraus.

Hier der Code der .exe:

// main.h
//
#include <windows.h>
#include <Dark3DCubeEnginedll.h>
#pragma comment(lib, "Dark3DCubeEngine.lib")

// Create a class, called MyApplication
//
class MyApplication : public DCE::Dark3DCubeEngine
{
public:

	MyApplication () {}
	virtual ~MyApplication () {}

};

// main.cpp
//
#include "main.h"

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
					LPSTR lpCmdLine, int nShowCmd)
{
	MSG msg;
	HWND hwnd;
	bool bDone = false;
	MyApplication * pApp = new MyApplication ();
	DCE::Dark3DCubeEngineProperties props;

	pApp->Initialize(props);
	pApp->SetWindowProperties(1200, 1000, 32);
	pApp->SetWindowColor(100, 250, 100);
	hwnd = pApp->OpenWindow(hInstance);

	if (hwnd)
	{
		MessageBox(NULL, "Fehler beim Initialisieren!", "Fehler aufgetreten",
				   MB_OK | MB_ICONEXCLAMATION);
	}

	while (!bDone)
	{
		while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
		{
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	}

	delete pApp;

	return 0;
}

Kann mir hier jemand helfen?

Gruss Patrick