初学者问题 超简单

[nomadli]

《Windows 程序设计》七长的程序：

x&0xFF y>>8
y<<8|x
作用那位大哥解释一下？
当把回车、空格、传给DefWindowProc后的发生了什么？


#include <windows.h>

#define DIVISIONS 5

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
LRESULT CALLBACK ChildWndProc (HWND, UINT, WPARAM, LPARAM) ;

TCHAR szChildClass[] = TEXT ("Checker3_Child") ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("Checker3") ;
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 ("Program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

wndclass.lpfnWndProc = ChildWndProc ;
wndclass.cbWndExtra = sizeof (long) ;
wndclass.hIcon = NULL ;
wndclass.lpszClassName = szChildClass ;

RegisterClass (&wndclass) ;

hwnd = CreateWindow (szAppName, TEXT ("Checker3 Mouse Hit-Test 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 CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static HWND hwndChild[DIVISIONS][DIVISIONS] ;
int cxBlock, cyBlock, x, y ;

switch (message)
{
case WM_CREATE :
for (x = 0 ; x < DIVISIONS ; x++)
for (y = 0 ; y < DIVISIONS ; y++)
hwndChild[x][y] = CreateWindow (szChildClass, NULL,
WS_CHILDWINDOW | WS_VISIBLE,
0, 0, 0, 0,
hwnd, (HMENU) (y << 8 | x),
(HINSTANCE) GetWindowLong (hwnd, GWL_HINSTANCE),
NULL) ;
return 0 ;

case WM_SIZE :
cxBlock = LOWORD (lParam) / DIVISIONS ;
cyBlock = HIWORD (lParam) / DIVISIONS ;

for (x = 0 ; x < DIVISIONS ; x++)
for (y = 0 ; y < DIVISIONS ; y++)
MoveWindow (hwndChild[x][y],
x * cxBlock, y * cyBlock,
cxBlock, cyBlock, TRUE) ;
return 0 ;

case WM_LBUTTONDOWN :
MessageBeep (0) ;
return 0 ;

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

LRESULT CALLBACK ChildWndProc (HWND hwnd, UINT message,
WPARAM wParam, LPARAM lParam)
{
HDC hdc ;
PAINTSTRUCT ps ;
RECT rect ;

switch (message)
{
case WM_CREATE :
SetWindowLong (hwnd, 0, 0) ; // on/off flag
return 0 ;

case WM_LBUTTONDOWN :
SetWindowLong (hwnd, 0, 1 ^ GetWindowLong (hwnd, 0)) ;
InvalidateRect (hwnd, NULL, FALSE) ;
return 0 ;

case WM_PAINT :
hdc = BeginPaint (hwnd, &ps) ;

GetClientRect (hwnd, &rect) ;
Rectangle (hdc, 0, 0, rect.right, rect.bottom) ;

if (GetWindowLong (hwnd, 0))
{
MoveToEx (hdc, 0, 0, NULL) ;
LineTo (hdc, rect.right, rect.bottom) ;
MoveToEx (hdc, 0, rect.bottom, NULL) ;
LineTo (hdc, rect.right, 0) ;
}

EndPaint (hwnd, &ps) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

[whx800]

路过

[photnman]

DefWindowProc
Calls the default window procedure, which provides default processing for any window message that an application does not process

[talentyang]

区别窗口!

[nomadli]

我觉的应该是x&0x0f才对，

因为不用自己处理才不知道啊，不用自己管，不是不用知道它到底发生了什么？

高手说说我该怎么给大家分开这100分？？？我一般都会给点

[RookieStar]

因为不用自己处理才不知道啊，不用自己管，不是不用知道它到底发生了什么？
////////////////////////////////////////////////////////////////////
不用知道它是怎么处理的。根据你自己的需要写对应的消息处理，那些你不想处理的就交给DefWindowProc，否则的话，由它们产生的消息积压在消息队列里，你就取不到后面有用的消息了。

[tangfulin]

试验一下不就知道了？试验中。。。

[lemon520]

x&0xFF x与上1111111111111111
y>>8 y向右移8位
y<<8|x y向左移8位再或x

当把回车、空格、传给DefWindowProc后的发生了什么？
回车，空格都有自己的 键码,传消息就是传键码

[nomadli]

我是问在程序中的作用，单独的意思我也知道啊，回车空格传出的具体过程例如windows给回调函数传了什么消息？

[RookieStar]

For a child window, hMenu specifies the child-window identifier, an integer value used by a dialog box control to notify its parent about events. The application determines the child-window identifier; it must be unique for all child windows with the same parent window.

这里y<<8|x主要是用来区别每个子窗口的标志，把y和x合为一个32位数，低8位为原x的值，8~15位为原y的值，这种处理保证了产生的每个HMENU正整数都是不同的。在你的程序里没其他作用，仅告诉父窗口如何区别这些子窗口。

[RookieStar]

当把回车、空格、传给DefWindowProc后的发生了什么？
///////////////////////////////////////////////
我觉得lemon520说的是对的。不过是表示这些你都不处理了，交由windows自己处理。用DefWindowProc保证了所有的消息都被处理（被你还是被windows自己）。

[nomadli]

我不小心把程序拷错了应该是：

#include <windows.h>

#define DIVISIONS 5

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
LRESULT CALLBACK ChildWndProc (HWND, UINT, WPARAM, LPARAM) ;

int idFocus = 0 ;
TCHAR szChildClass[] = TEXT ("Checker4_Child") ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("Checker4") ;
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 ("Program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

wndclass.lpfnWndProc = ChildWndProc ;
wndclass.cbWndExtra = sizeof (long) ;
wndclass.hIcon = NULL ;
wndclass.lpszClassName = szChildClass ;

RegisterClass (&wndclass) ;

hwnd = CreateWindow (szAppName, TEXT ("Checker4 Mouse Hit-Test 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 CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static HWND hwndChild[DIVISIONS][DIVISIONS] ;
int cxBlock, cyBlock, x, y ;

switch (message)
{
case WM_CREATE :
for (x = 0 ; x < DIVISIONS ; x++)
for (y = 0 ; y < DIVISIONS ; y++)
hwndChild[x][y] = CreateWindow (szChildClass, NULL,
WS_CHILDWINDOW | WS_VISIBLE,
0, 0, 0, 0,
hwnd, (HMENU) (y << 8 | x),
(HINSTANCE) GetWindowLong (hwnd, GWL_HINSTANCE),
NULL) ;
return 0 ;

case WM_SIZE :
cxBlock = LOWORD (lParam) / DIVISIONS ;
cyBlock = HIWORD (lParam) / DIVISIONS ;

for (x = 0 ; x < DIVISIONS ; x++)
for (y = 0 ; y < DIVISIONS ; y++)
MoveWindow (hwndChild[x][y],
x * cxBlock, y * cyBlock,
cxBlock, cyBlock, TRUE) ;
return 0 ;

case WM_LBUTTONDOWN :
MessageBeep (0) ;
return 0 ;

// On set-focus message, set focus to child window

case WM_SETFOCUS:
SetFocus (GetDlgItem (hwnd, idFocus)) ;
return 0 ;

// On key-down message, possibly change the focus window

case WM_KEYDOWN:
x = idFocus & 0xFF ;//我认为应该是x=idFocus&0x0f????????????
y = idFocus >> 8 ;

switch (wParam)
{
case VK_UP: y-- ; break ;
case VK_DOWN: y++ ; break ;
case VK_LEFT: x-- ; break ;
case VK_RIGHT: x++ ; break ;
case VK_HOME: x = y = 0 ; break ;
case VK_END: x = y = DIVISIONS - 1 ; break ;
default: return 0 ;
}

x = (x + DIVISIONS) % DIVISIONS ;
y = (y + DIVISIONS) % DIVISIONS ;

idFocus = y << 8 | x ;

SetFocus (GetDlgItem (hwnd, idFocus)) ;
return 0 ;

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

LRESULT CALLBACK ChildWndProc (HWND hwnd, UINT message,
WPARAM wParam, LPARAM lParam)
{
HDC hdc ;
PAINTSTRUCT ps ;
RECT rect ;

switch (message)
{
case WM_CREATE :
SetWindowLong (hwnd, 0, 0) ; // on/off flag
return 0 ;

case WM_KEYDOWN:
// Send most key presses to the parent window

if (wParam != VK_RETURN && wParam != VK_SPACE)
{
SendMessage (GetParent (hwnd), message, wParam, lParam) ;
return 0 ;
}
// For Return and Space, fall through to toggle the square
//可是这样发生了什么我不知道哎，难道我不该问？？？？？？？？
case WM_LBUTTONDOWN :
SetWindowLong (hwnd, 0, 1 ^ GetWindowLong (hwnd, 0)) ;
SetFocus (hwnd) ;
InvalidateRect (hwnd, NULL, FALSE) ;
return 0 ;

// For focus messages, invalidate the window for repaint

case WM_SETFOCUS:
idFocus = GetWindowLong (hwnd, GWL_ID) ;

// Fall through

case WM_KILLFOCUS:
InvalidateRect (hwnd, NULL, TRUE) ;
return 0 ;

case WM_PAINT :
hdc = BeginPaint (hwnd, &ps) ;

GetClientRect (hwnd, &rect) ;
Rectangle (hdc, 0, 0, rect.right, rect.bottom) ;

// Draw the "x" mark

if (GetWindowLong (hwnd, 0))
{
MoveToEx (hdc, 0, 0, NULL) ;
LineTo (hdc, rect.right, rect.bottom) ;
MoveToEx (hdc, 0, rect.bottom, NULL) ;
LineTo (hdc, rect.right, 0) ;
}

// Draw the "focus" rectangle

if (hwnd == GetFocus ())
{
rect.left += rect.right / 10 ;
rect.right -= rect.left ;
rect.top += rect.bottom / 10 ;
rect.bottom -= rect.top ;

SelectObject (hdc, GetStockObject (NULL_BRUSH)) ;
SelectObject (hdc, CreatePen (PS_DASH, 0, 0)) ;
Rectangle (hdc, rect.left, rect.top, rect.right, rect.bottom) ;
DeleteObject (SelectObject (hdc, GetStockObject (BLACK_PEN))) ;
}

EndPaint (hwnd, &ps) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

[nomadli]

我问的问题在代码中用注释写着，要分就让我最少知道应该是： x = idFocus & 0xFF 还是x=idFocus&0x0f。


郁闷我还是第一次这么长时间没结贴，以前我就算没人回答问题我都很快给了分可这个应该有人告诉我啊。

[lemon520]

你拷的代码只能说明了该程序不对Enter和Space进行处理，当然你可以修改代码，自己拦截消息，然后做你想做的事情

[hewittlee]

up

[starluck]

看到WINDOWS程序设计的题目就头痛

[amani02]

这也能叫超简单？偶不会！

[nomadli]

郁闷，没人理，给谁分？？

[nomadli]

谁第一个回答了：是应该用： x = idFocus & 0xFF 还是用x=idFocus&0x0f。

80分都给了他。