Before I mention anything I have checked the spelling and method declaration so don't reply saying check those things. I am using c++ in vs2003. I have an Application class that uses a static window procedure. In my window procedure the WM_CREATE calls an OnLoad method. In my derived class I override the method. The weird thing is that the base class's method gets called instead of the derived class. I also have an OnPaint and OnClose method that work fine. I have checked the spelling and declaration so many times. I have used break points to figure whats happening and this is where I am now. I don't understand why.
class IApplication
{
private:
HINSTANCE m_hInst;
HWND m_hWnd;
std::string m_strClassName;
public:
IApplication(HINSTANCE hInst, std::string strClassName, std::string strTitle = "Default");
~IApplication(void);
HINSTANCE GethInst(void);
HWND GethWnd(void);
void Run(void);
void Show(bool bShow = true);
void SetFont(HFONT hFont = (HFONT)GetStockObject(DEFAULT_GUI_FONT));
protected:
static LRESULT CALLBACK StaticWndProc(HWND hWnd, UINT iMsg, WPARAM wParam, LPARAM lParam);
inline static IApplication* GetObjectFromWindow(HWND hWnd);
LRESULT CALLBACK WndProc(HWND hWnd, UINT iMsg, WPARAM wParam, LPARAM lParam);
virtual void OnLoad(void);
virtual void OnClose(void);
virtual void OnPaint(void);
};
IApplication::IApplication(HINSTANCE hInst, std::string strClassName, std::string strTitle)
{
m_hInst = hInst;
WNDCLASSEX wcex;
wcex.cbClsExtra = 0;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.cbWndExtra = 0;
wcex.hbrBackground = (HBRUSH)GetStockObject(0);
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wcex.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
wcex.hInstance = g_hInst;
wcex.lpfnWndProc = StaticWndProc;
wcex.lpszClassName = strClassName.c_str();
wcex.lpszMenuName = NULL;
wcex.style = CS_CLASSDC;
if(!RegisterClassEx(&wcex))
{
//Log Error
}
m_hWnd = CreateWindow(strClassName.c_str(), strTitle.c_str(),
WS_OVERLAPPEDWINDOW, 0, 0, 300, 300, NULL, NULL, g_hInst, (void*)this);
if(!m_hWnd)
{
//Log Error
}
//Set Globals
g_hWnd = m_hWnd;
g_hInst = m_hInst;
UpdateWindow(m_hWnd);
}
IApplication::~IApplication(void)
{
UnregisterClass("DEFAULT", g_hInst);
}
HINSTANCE IApplication::GethInst(void)
{
return m_hInst;
}
HWND IApplication::GethWnd(void)
{
return m_hWnd;
}
void IApplication::Run(void)
{
MSG msg;
ZeroMemory(&msg, sizeof(MSG));
while(msg.message != WM_QUIT)
{
if(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
}
void IApplication::Show(bool bShow)
{
if(bShow)
{
ShowWindow(m_hWnd, SW_SHOW);
}
else
{
ShowWindow(m_hWnd, SW_HIDE);
}
}
void IApplication::SetFont(HFONT hFont)
{
SendMessage(m_hWnd, WM_SETFONT, (WPARAM)hFont, MAKELPARAM(FALSE, 0));
}
LRESULT CALLBACK IApplication::StaticWndProc(HWND hWnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
IApplication *app = NULL;
if(iMsg == WM_NCCREATE)
{
SetWindowLongPtr(hWnd, GWL_USERDATA, reinterpret_cast<long>((LPCREATESTRUCT(lParam))->lpCreateParams));
}
app = GetObjectFromWindow(hWnd);
if(app)
{
return app->WndProc(hWnd, iMsg, wParam, lParam);
}
else
{
return DefWindowProc(hWnd, iMsg, wParam, lParam);
}
}
IApplication* IApplication::GetObjectFromWindow(HWND hWnd)
{
return reinterpret_cast<IApplication*>(GetWindowLongPtr(hWnd, GWL_USERDATA));
}
LRESULT CALLBACK IApplication::WndProc(HWND hWnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
switch(iMsg)
{
case WM_CREATE:
OnLoad();
break;
case WM_DESTROY:
OnClose();
PostQuitMessage(0);
break;
case WM_PAINT:
OnPaint();
break;
}
return DefWindowProc(hWnd, iMsg, wParam, lParam);
}
void IApplication::OnLoad(void)
{
MessageBox(NULL, "Load", "", MB_OK);
}
void IApplication::OnClose(void)
{
}
void IApplication::OnPaint(void)
{
}
class Application : public IApplication
{
public:
Application(HINSTANCE hInst, std::string strClassName, std::string strTitle);
~Application(void);
protected:
void OnLoad(void);
void OnPaint(void);
void OnClose(void);
};
Application::Application(HINSTANCE hInst, std::string strClassName,
std::string strTitle = "Default") : IApplication(hInst, strClassName, strTitle)
{
}
Application::~Application()
{
}
void Application::OnLoad(void)
{
Show(true);
}
void Application::OnPaint(void)
{
HDC hdc;
hdc = GetDC(g_hWnd);
TextOut(hdc, 100, 100, "Hello World!", 12);
}
void Application::OnClose(void)
{
//MessageBox(NULL, "Close", "", MB_OK);
}
If you insist on saying "DUH", try to make a post that makes a little more sense
