win sdk编程,窗口类重新注册后ListBox无法添加数据项

[sugelade]

很简单的一个例子：注册窗口类，lpfnWndProc指向WndProc,然后创建一个win窗体，接着重新注册窗口类，lpfnWndProc指向WndProcListBox,然后创建一个ListBox窗口（父窗口是第一个创建的win窗体），想在WndProcListBox的消息循环中的WM_CREATE消息中往ListBox增加Item,但不起作用。搞了两天都没弄出来，郁闷！代码如下：
typedef struct
{
HWND hwnd ;
int cxClient ;
int cyClient ;
int cyChar ;
BOOL bKill ;
}
PARAMS, *PPARAMS ;

LRESULT APIENTRY WndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("Multi2") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;

wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc = WndProc ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;

if (!RegisterClass (&wndclass))
{
MessageBox (NULL, TEXT ("This program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

hwnd = CreateWindow (szAppName, TEXT ("Multitasking Demo"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
CW_USEDEFAULT, CW_USEDEFAULT,
NULL, NULL, hInstance, NULL) ;

ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;

while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}

LRESULT APIENTRY WndProcListBox (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static PARAMS params ;
switch (message)
{
case WM_CREATE:
params.hwnd = hwnd ;
params.cyChar = HIWORD (GetDialogBaseUnits ()) ;
SendMessage(hwnd, LB_ADDSTRING, 0, (LPARAM)"Hi there!");
return 0 ;

case WM_SIZE:
params.cyClient = HIWORD (lParam) ;
return 0 ;

case WM_DESTROY:
params.bKill = TRUE ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

LRESULT APIENTRY WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static HWND hwndChild ;
static TCHAR szChildClass[] = TEXT ("Child1") ;
static WNDPROC ChildProc = WndProcListBox ;
HINSTANCE hInstance ;
int i, cxClient, cyClient ;
WNDCLASS wndclass ;

switch (message)
{
case WM_CREATE:
hInstance = (HINSTANCE) GetWindowLong (hwnd, GWL_HINSTANCE) ;

wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = NULL ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;

wndclass.lpfnWndProc = ChildProc ;
wndclass.lpszClassName = szChildClass ;

RegisterClass (&wndclass) ;

hwndChild = CreateWindow (szChildClass, NULL,
WS_CHILD | WS_VISIBLE | LBS_STANDARD,
0, 0, 0, 0,
hwnd, (HMENU) 0, hInstance, NULL) ;

}
return 0 ;

case WM_SIZE:
cxClient = LOWORD (lParam) ;
cyClient = HIWORD (lParam) ;

MoveWindow (hwndChild[i], 0,0,
cxClient / 2, cyClient / 2, TRUE) ;
return 0 ;

case WM_CHAR:
if (wParam == '\x1B')
DestroyWindow (hwnd) ;

return 0 ;

case WM_DESTROY:
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

[sugelade]

木有人回答？加到100分

[菜牛]

不得不说你很勇敢，创建 ListBox 就创建呗，注册它干啥。

[sugelade]

呼，终于有人回复了，虽然不是我想要的答案。 专门为ListBox注册窗口是因为想在WndProListBox中创建一个线程，这个线程将访问服务器，根据后台数据对ListBox增减Item.

[菜牛]

引用 3 楼 sugelade 的回复:

呼，终于有人回复了，虽然不是我想要的答案。 专门为ListBox注册窗口是因为想在WndProListBox中创建一个线程，这个线程将访问服务器，根据后台数据对ListBox增减Item.

这跟你要访问ListBox有啥关系？你注册了窗口意思是自己去实现这个窗口的过程……也就是说不再是什么ListBox了。去看看子类化是什么概念。

[sugelade]

很有启发，谢谢楼上的建议。