1
我下面MSDN上的教程：http://msdn.microsoft.com/en-us/library/windows/desktop/ff381400(v=vs.85).aspx純虛擬方法調用，終止
它展示瞭如何使一個類中WINAPI創建窗口。
我做了與他們完全相同的事情，除了我把創造代碼放在構造函數中。
運行時，它會給出純虛擬方法，稱爲錯誤，並終止沒有解釋的程序。
template<typename T>
class Form
{
public:
Form(std::string Title, std::string Class, /*All other params*/);
private:
static LRESULT __stdcall WindowProcedure(HWND Hwnd, UINT Msg, WPARAM wParam, LPARAM lParam);
protected:
HWND WindowHandle = nullptr;
virtual LRESULT HandleMessages(UINT Msg, WPARAM wParam, LPARAM lParam) = 0;
};
template<typename T>
Form<T>::Form(std::string Title, std::string Class, /*All Other Params*/)
{
WNDCLASSEX WndClass = {/*Filled in with other params*/};
RegisterClassEx(&WndClass);
WindowHandle = CreateWindowEx(/*Other params*/, this);
}
template<typename T>
LRESULT __stdcall Form<T>::WindowProcedure(HWND Hwnd, UINT Msg, WPARAM wParam, LPARAM lParam)
{
T* Data = nullptr;
switch (Msg)
{
case WM_NCCREATE:
{
CREATESTRUCT* pCreate = (CREATESTRUCT*)lParam;
Data = reinterpret_cast<T*>(pCreate->lpCreateParams);
SetWindowLongPtr(Hwnd, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(Data));
break;
}
default:
{
Data = reinterpret_cast<T*>(GetWindowLongPtr(Hwnd, GWLP_USERDATA));
return Data ? Data->HandleMessages(Msg, wParam, lParam) : DefWindowProc(Hwnd, Msg, wParam, lParam);
}
}
return 0;
}
那麼我的主要窗口：
class MainWindow : public Form<MainWindow>
{
public:
MainWindow(std::string Title, /*Other params*/);
LRESULT HandleMessages(UINT Msg, WPARAM wParam, LPARAM lParam);
HWND WindowHandle() {return Form::WindowHandle;}
};
MainWindow::MainWindow(std::string Title, std::string Class, /*Other params*/) {}
LRESULT MainWindow::HandleMessages(UINT Msg, WPARAM wParam, LPARAM lParam)
{
switch(Msg)
{
case WM_CREATE:
{
}
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(WindowHandle(), Msg, wParam, lParam);
}
return 0;
}
這是所有。爲什麼它會給我這個錯誤，我該如何解決？