为了将 WNDPROC
用作对象方法,我采用了您在那里找到的典型解决方案,但看起来 WM_DESTROY
消息并未发送到对象窗口自身的WNDPROC
,关闭窗口后程序不退出。
我的窗口类如下所示(删除了不相关的代码):
class MyWindow : MyApp
{
public:
MyWindow();
void Create(void);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
private:
HWND _hWnd;
};
void MyWindow::Create()
{
// Here I register my class and call CreateWindowEx
// Everything works fine so far
// Part of the code where I assign the static WNDPROC
WNDCLASSEXW wcex;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = MyApp::WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = this->Instance;
wcex.hIcon = LoadIcon(this->Instance, MAKEINTRESOURCE(32512));
wcex.hCursor = LoadCursor(nullptr, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
wcex.lpszMenuName = NULL;
wcex.lpszClassName = "MyWindowClass";
wcex.hIconSm = LoadIcon(this->Instance, MAKEINTRESOURCE(32512));
RegisterClassExW(&wcex);
this->_hWnd = CreateWindowExW(
WS_EX_TOOLWINDOW | WS_EX_TOOLWINDOW,
wcex.lpszClassName,
"Window Title",
WS_POPUP,
10, 10,
600, 400,
nullptr,
nullptr,
this->Instance,
nullptr
);
ShowWindow(this->_hWnd, SW_SHOW);
UpdateWindow(this->_hWnd);
}
LRESULT CALLBACK MyWindow::WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch (msg)
{
case WM_CREATE:
{
// If I place a MessageBox here, it shows up
}
break;
case WM_DESTROY:
// It never gets to this point
// Decrease windows count
this->WindowsCount--;
PostQuitMessage(0);
break;
break;
default:
return DefWindowProc(hWnd, msg, wParam, lParam);
}
return 0;
}
现在是一个包含静态 WNDPROC 的类,它是在创建时分配的
class MyApp
{
public:
static HINSTANCE Instance;
static int WindowsCount;
MyApp();
static LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
};
和实现
LRESULT CALLBACK MyApp::WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
// Window object
MyWindow* myWindow = NULL;
if (msg == WM_CREATE) {
myWindow = reinterpret_cast<MyWindow *>(((LPCREATESTRUCT)lParam)->lpCreateParams);
SetWindowLongPtr(hWnd, GWLP_USERDATA, (LONG_PTR)myWindow);
}
else {
myWindow = reinterpret_cast<MyWindow *>(GetWindowLongPtr(hWnd, GWLP_USERDATA));
}
// If window not identified, identify now
if (myWindow) {
return myWindow->WndProc(hWnd, msg, wParam, lParam);
}
// Call window object's processor
return DefWindowProc(hWnd, msg, wParam, lParam);
}
WM_CLOSE
消息也没有被捕获。我真的不明白为什么这些消息不传递
最佳答案
您正在设置 lpParam
CreateWindowEx()
的参数至 nullptr
, 所以 myWindow
总是 nullptr
在 MyApp::WndProc()
,因此 MyWindow::WndProc()
永远不会被调用。你需要通过 this
而不是 nullptr
.
您也没有进行任何错误检查以确保 RegisterClassExW()
和 CreateWindowEx()
在调用 ShowWindow()
之前成功/UpdateWindow()
.
另外,考虑使用 SetWindowSubclass()
而不是 (Get|Set)WindowLongPtr(GWLP_USERDATA)
.参见 Subclassing Controls在 MSDN 上,以及 Raymond Chen 在 Safer Subclassing 上的博客文章.
关于c++ - WM_DESTROY 未在包装的 WndProc 中调用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48029275/