I am having issues with my code. I am making a class to wrap around some WinAPI to create GUIs, however I am having issues when attempting to register the class.
My code:
inline Window::Window(const TCHAR *windowName, const int x, const int y, const int width, const int height, const TCHAR *className) : abstractWindow() {
Window(0, className, windowName, WS_OVERLAPPEDWINDOW, x, y, width, height, NULL, NULL, NULL, NULL);
}
Window::Window(const DWORD dwExStyle, const TCHAR *lpClassName, const TCHAR *lpWindowName, const DWORD dwStyle, const int x, const int y, const int nWidth, const int nHeight, const HWND hWndParent, const HMENU hMenu, const HINSTANCE hInstance, const LPVOID lpParam) : abstractWindow() {
_proc = (WNDPROC*) &abstractWindow::msgRouter;
_styleEx = dwExStyle;
_className = (!lpClassName) ? TEXT("MyGuiClass") : lpClassName;
_windowName = lpWindowName;
_style = dwStyle;
_x = x;
_y = y;
_width = nWidth;
_height = nHeight;
_hwndParent = hWndParent;
_hInstance = (!hInstance) ? ::GetModuleHandle(NULL) : hInstance;
_hMenu = hMenu;
_lpParam = lpParam;
_wndClassEx.cbSize = sizeof(_wndClassEx);
_wndClassEx.style = CS_HREDRAW | CS_VREDRAW;
_wndClassEx.lpfnWndProc = abstractWindow::msgRouter;
_wndClassEx.cbClsExtra = 0;
_wndClassEx.cbWndExtra = 0;
_wndClassEx.hInstance = _hInstance;
_wndClassEx.hIcon = ::LoadIcon(NULL, IDI_APPLICATION);
_wndClassEx.hCursor = ::LoadCursor(NULL, IDC_ARROW);
_wndClassEx.hbrBackground = (HBRUSH) COLOR_WINDOW;
_wndClassEx.lpszMenuName = NULL;
_wndClassEx.lpszClassName = _className;
_wndClassEx.hIconSm = ::LoadIcon(NULL, IDI_APPLICATION);
}
_wndClassEx is already defined in the class header as of WNDCLASSEX and the register function simply runs RegisterClassEx(&_wndClassEx).
The following are how I call these classes: (However only one is called at a time)
Window gui (TEXT("Title"), 10, 10, 500, 250);
Window gui (0, NULL, TEXT("Title"), WS_OVERLAPPEDWINDOW, 10, 10, 500, 200, NULL, NULL, hInstance, NULL);
The second one works perfectly fine, however when I call the first (shorter parameters, which puts it through to the second) class registration fails. I have completely written the _wndClassEx as well as gone through every single one and modified it to no success. I have gone through with a debugger and everything seems fine. So I have absolutely no idea what to do.
By the way, abstractWindow::msgRouter is static.
Thanks.
The problem is with this constructor:
inline Window::Window(const TCHAR *windowName, const int x, const int y, const int width, const int height, const TCHAR *className) : abstractWindow() {
Window(0, className, windowName, WS_OVERLAPPEDWINDOW, x, y, width, height, NULL, NULL, NULL, NULL);
}
You can't call a constructor from another constructor like that. What ends up happening is that a temporary object is created and then immediatly discarded. The way to achieve that (this only works if you have a compiler which implements this feature from the new C++11 Standard) is if you say
inline Window::Window(const TCHAR *windowName, const int x, const int y, const int width, const int height, const TCHAR *className) : Window(0, className, windowName, WS_OVERLAPPEDWINDOW, x, y, width, height, NULL, NULL, NULL, NULL) {};
Another way would be to do what @aztaroth said: create a separate method and call it from both constructors (that works even with an older compiler).
编写一个初始化窗口的方法(基本上剪切并粘贴第二个构造函数),然后使用两个构造函数中的适当值调用它。
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