14 Windows编程——SetWindowLong
使用默认窗口处理函数，源码
#include<Windows.h>
#include<Windowsx.h> LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam); int WinMain(HINSTANCE hInst, HINSTANCE tmp, LPSTR szCmd, int nShow)
{
WNDCLASS WndClass;
TCHAR* ClassName = TEXT("MyClass");
HWND hwnd;
MSG msg;
HBRUSH hBrush = CreateSolidBrush(RGB(, , )); WndClass.cbClsExtra = ;
WndClass.cbWndExtra = ;
WndClass.hbrBackground = hBrush;
WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
WndClass.hInstance = hInst;
WndClass.lpfnWndProc = WindProc;
WndClass.lpszClassName = ClassName;
WndClass.lpszMenuName = NULL;
WndClass.style = CS_VREDRAW | CS_HREDRAW; if (!RegisterClass(&WndClass))
{
MessageBox(NULL, TEXT("Gegister Class Fail!!"), TEXT("error"), MB_OK);
return ;
} //CreateWindow返回之前，会发送WM_CREATE消息
hwnd = CreateWindow(ClassName, TEXT("Hello"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, , , NULL, NULL, hInst, NULL);
if (hwnd == NULL)
{
MessageBox(NULL, TEXT("Create Window Fail!!"), TEXT("error"), MB_OK);
return ;
}
ShowWindow(hwnd, nShow);
UpdateWindow(hwnd); while (GetMessage(&msg, NULL, , ))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
} return ;
} LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT pt;
static int cx, cy;
HDC hdc;
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
switch (message)
{
case WM_CREATE:
//SetWindowLong(hwnd, GWL_WNDPROC, (LONG)MyProc);
return ;
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
hdc = BeginPaint(hwnd, &pt);
HBRUSH hBrush = CreateSolidBrush(RGB(,,));
SelectObject(hdc, hBrush);
Rectangle(hdc, , , cx/, cy/);
DeleteObject(hBrush);
EndPaint(hwnd, &pt);
return ;
case WM_DESTROY:
PostQuitMessage();
return ;
default:
break;
} return DefWindowProc(hwnd, message, wParam, lParam);
} LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
static int cx, cy; switch (message)
{
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps); EndPaint(hwnd, &ps);
return ;
default:
break;
}
return DefWindowProc(hwnd, message, wParam, lParam);
}
运行结果(只能使用Alt+F4关闭)：
使用SetWindowLong替换窗户口处理函数，源码
#include<Windows.h>
#include<Windowsx.h> LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam); int WinMain(HINSTANCE hInst, HINSTANCE tmp, LPSTR szCmd, int nShow)
{
WNDCLASS WndClass;
TCHAR* ClassName = TEXT("MyClass");
HWND hwnd;
MSG msg;
HBRUSH hBrush = CreateSolidBrush(RGB(, , )); WndClass.cbClsExtra = ;
WndClass.cbWndExtra = ;
WndClass.hbrBackground = hBrush;
WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
WndClass.hInstance = hInst;
WndClass.lpfnWndProc = WindProc;
WndClass.lpszClassName = ClassName;
WndClass.lpszMenuName = NULL;
WndClass.style = CS_VREDRAW | CS_HREDRAW; if (!RegisterClass(&WndClass))
{
MessageBox(NULL, TEXT("Gegister Class Fail!!"), TEXT("error"), MB_OK);
return ;
} //CreateWindow返回之前，会发送WM_CREATE消息
hwnd = CreateWindow(ClassName, TEXT("Hello"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, , , NULL, NULL, hInst, NULL);
if (hwnd == NULL)
{
MessageBox(NULL, TEXT("Create Window Fail!!"), TEXT("error"), MB_OK);
return ;
}
ShowWindow(hwnd, nShow);
UpdateWindow(hwnd); while (GetMessage(&msg, NULL, , ))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
} return ;
} LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT pt;
static int cx, cy;
HDC hdc;
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
switch (message)
{
case WM_CREATE:
SetWindowLong(hwnd, GWL_WNDPROC, (LONG)MyProc);
return ;
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
hdc = BeginPaint(hwnd, &pt);
HBRUSH hBrush = CreateSolidBrush(RGB(,,));
SelectObject(hdc, hBrush);
Rectangle(hdc, , , cx/, cy/);
DeleteObject(hBrush);
EndPaint(hwnd, &pt);
return ;
case WM_DESTROY:
PostQuitMessage();
return ;
default:
break;
} return DefWindowProc(hwnd, message, wParam, lParam);
} LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
static int cx, cy; switch (message)
{
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
SelectObject(hdc, hBrush);
Rectangle(hdc, cx / , cy / , cx, cy);
DeleteObject(hBrush);
EndPaint(hwnd, &ps);
return ;
default:
break;
}
return DefWindowProc(hwnd, message, wParam, lParam);
}
运行结果：
使用SetWindowLong接管原来窗口处理函数后，把WM_PAINT消息先在MyProc处理一次 ，然后交给原来的窗口处理函数再处理一次。但是发现并没有绘制出原来窗口处理函数绘制的图形
#include<Windows.h>
#include<Windowsx.h> LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam); int WinMain(HINSTANCE hInst, HINSTANCE tmp, LPSTR szCmd, int nShow)
{
WNDCLASS WndClass;
TCHAR* ClassName = TEXT("MyClass");
HWND hwnd;
MSG msg;
HBRUSH hBrush = CreateSolidBrush(RGB(, , )); WndClass.cbClsExtra = ;
WndClass.cbWndExtra = ;
WndClass.hbrBackground = hBrush;
WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
WndClass.hInstance = hInst;
WndClass.lpfnWndProc = WindProc;
WndClass.lpszClassName = ClassName;
WndClass.lpszMenuName = NULL;
WndClass.style = CS_VREDRAW | CS_HREDRAW; if (!RegisterClass(&WndClass))
{
MessageBox(NULL, TEXT("Gegister Class Fail!!"), TEXT("error"), MB_OK);
return ;
} //CreateWindow返回之前，会发送WM_CREATE消息
hwnd = CreateWindow(ClassName, TEXT("Hello"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, , , NULL, NULL, hInst, NULL);
if (hwnd == NULL)
{
MessageBox(NULL, TEXT("Create Window Fail!!"), TEXT("error"), MB_OK);
return ;
}
ShowWindow(hwnd, nShow);
UpdateWindow(hwnd); while (GetMessage(&msg, NULL, , ))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
} return ;
} LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT pt;
static int cx, cy;
HDC hdc;
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
switch (message)
{
case WM_CREATE:
SetWindowLong(hwnd, GWL_WNDPROC, (LONG)MyProc);
return ;
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
hdc = BeginPaint(hwnd, &pt);
HBRUSH hBrush = CreateSolidBrush(RGB(,,));
SelectObject(hdc, hBrush);
Rectangle(hdc, , , cx/, cy/);
DeleteObject(hBrush);
EndPaint(hwnd, &pt);
return ;
case WM_DESTROY:
PostQuitMessage();
return ;
default:
break;
} return DefWindowProc(hwnd, message, wParam, lParam);
} LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
static int cx, cy; switch (message)
{
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
SelectObject(hdc, hBrush);
Rectangle(hdc, cx / , cy / , cx, cy);
DeleteObject(hBrush);
EndPaint(hwnd, &ps);
//return 0;
break;
default:
break;
}
return WindProc(hwnd, message, wParam, lParam);
}
经调试，发现WindProc函数中WM_PAINT消息，cx=0,cy=0。绘制了，只不过绘制的矩形坐标时（ 0 0 0 0），修改如下
方式① 源码
#include<Windows.h>
#include<Windowsx.h> LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam); int WinMain(HINSTANCE hInst, HINSTANCE tmp, LPSTR szCmd, int nShow)
{
WNDCLASS WndClass;
TCHAR* ClassName = TEXT("MyClass");
HWND hwnd;
MSG msg;
HBRUSH hBrush = CreateSolidBrush(RGB(, , )); WndClass.cbClsExtra = ;
WndClass.cbWndExtra = ;
WndClass.hbrBackground = hBrush;
WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
WndClass.hInstance = hInst;
WndClass.lpfnWndProc = WindProc;
WndClass.lpszClassName = ClassName;
WndClass.lpszMenuName = NULL;
WndClass.style = CS_VREDRAW | CS_HREDRAW; if (!RegisterClass(&WndClass))
{
MessageBox(NULL, TEXT("Gegister Class Fail!!"), TEXT("error"), MB_OK);
return ;
} //CreateWindow返回之前，会发送WM_CREATE消息
hwnd = CreateWindow(ClassName, TEXT("Hello"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, , , NULL, NULL, hInst, NULL);
if (hwnd == NULL)
{
MessageBox(NULL, TEXT("Create Window Fail!!"), TEXT("error"), MB_OK);
return ;
}
ShowWindow(hwnd, nShow);
UpdateWindow(hwnd); while (GetMessage(&msg, NULL, , ))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
} return ;
} LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT pt;
static int cx, cy;
HDC hdc;
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
switch (message)
{
case WM_CREATE:
SetWindowLong(hwnd, GWL_WNDPROC, (LONG)MyProc);
return ;
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
InvalidateRect(hwnd, NULL, FALSE);
hdc = BeginPaint(hwnd, &pt);
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
SelectObject(hdc, hBrush);
Rectangle(hdc, , , cx / , cy / );
DeleteObject(hBrush);
EndPaint(hwnd, &pt);
return ;
case WM_DESTROY:
PostQuitMessage();
return ;
default:
break;
} return DefWindowProc(hwnd, message, wParam, lParam);
} LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
static int cx, cy; switch (message)
{
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
break;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
SelectObject(hdc, hBrush);
Rectangle(hdc, cx / , cy / , cx, cy);
DeleteObject(hBrush);
EndPaint(hwnd, &ps);
break;
default:
break;
}
return WindProc(hwnd, message, wParam, lParam);
}
方式② 源码
#include<Windows.h>
#include<Windowsx.h> LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam); int WinMain(HINSTANCE hInst, HINSTANCE tmp, LPSTR szCmd, int nShow)
{
WNDCLASS WndClass;
TCHAR* ClassName = TEXT("MyClass");
HWND hwnd;
MSG msg;
HBRUSH hBrush = CreateSolidBrush(RGB(, , )); WndClass.cbClsExtra = ;
WndClass.cbWndExtra = ;
WndClass.hbrBackground = hBrush;
WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
WndClass.hInstance = hInst;
WndClass.lpfnWndProc = WindProc;
WndClass.lpszClassName = ClassName;
WndClass.lpszMenuName = NULL;
WndClass.style = CS_VREDRAW | CS_HREDRAW; if (!RegisterClass(&WndClass))
{
MessageBox(NULL, TEXT("Gegister Class Fail!!"), TEXT("error"), MB_OK);
return ;
} //CreateWindow返回之前，会发送WM_CREATE消息
hwnd = CreateWindow(ClassName, TEXT("Hello"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, , , NULL, NULL, hInst, NULL);
if (hwnd == NULL)
{
MessageBox(NULL, TEXT("Create Window Fail!!"), TEXT("error"), MB_OK);
return ;
}
ShowWindow(hwnd, nShow);
UpdateWindow(hwnd); while (GetMessage(&msg, NULL, , ))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
} return ;
} LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT pt;
static int cx, cy;
HDC hdc;
RECT rect;
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
switch (message)
{
case WM_CREATE:
SetWindowLong(hwnd, GWL_WNDPROC, (LONG)MyProc);
return ;
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
rect.left = ;
rect.bottom = cy / ;
rect.right = cx / ;
rect.top = ;
InvalidateRect(hwnd, &rect, TRUE);
hdc = BeginPaint(hwnd, &pt);
HBRUSH hBrush = CreateSolidBrush(RGB(,,));
SelectObject(hdc, hBrush);
Rectangle(hdc, , , cx/, cy/);
DeleteObject(hBrush);
EndPaint(hwnd, &pt);
return ;
case WM_DESTROY:
PostQuitMessage();
return ;
default:
break;
} return DefWindowProc(hwnd, message, wParam, lParam);
} LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
static int cx, cy; switch (message)
{
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
break;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
SelectObject(hdc, hBrush);
Rectangle(hdc, cx / , cy / , cx, cy);
DeleteObject(hBrush);
EndPaint(hwnd, &ps);
break;
default:
break;
}
return WindProc(hwnd, message, wParam, lParam);
}
运行结果：
借助SetWindowLong创建白板窗口
源码
#include<Windows.h>
#include<Windowsx.h> LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam); int WinMain(HINSTANCE hInst, HINSTANCE tmp, LPSTR szCmd, int nShow)
{
WNDCLASS WndClass;
TCHAR* ClassName = TEXT("MyClass");
HWND hwnd;
MSG msg;
HBRUSH hBrush = CreateSolidBrush(RGB(, , )); WndClass.cbClsExtra = ;
WndClass.cbWndExtra = ;
WndClass.hbrBackground = hBrush;
WndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
WndClass.hInstance = hInst;
WndClass.lpfnWndProc = WindProc;
WndClass.lpszClassName = ClassName;
WndClass.lpszMenuName = NULL;
WndClass.style = CS_VREDRAW | CS_HREDRAW; if (!RegisterClass(&WndClass))
{
MessageBox(NULL, TEXT("Gegister Class Fail!!"), TEXT("error"), MB_OK);
return ;
} //CreateWindow返回之前，会发送WM_CREATE消息
hwnd = CreateWindow(ClassName, TEXT("Hello"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, , , NULL, NULL, hInst, NULL);
if (hwnd == NULL)
{
MessageBox(NULL, TEXT("Create Window Fail!!"), TEXT("error"), MB_OK);
return ;
}
ShowWindow(hwnd, nShow);
UpdateWindow(hwnd); while (GetMessage(&msg, NULL, , ))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
} return ;
} LRESULT CALLBACK WindProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT pt;
static int cx, cy;
HDC hdc;
RECT rect;
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
switch (message)
{
case WM_CREATE:
SetWindowLong(hwnd, GWL_STYLE, (LONG)WS_POPUP);
return ;
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
return ;
case WM_PAINT:
rect.left = ;
rect.bottom = cy / ;
rect.right = cx / ;
rect.top = ;
InvalidateRect(hwnd, &rect, TRUE);
hdc = BeginPaint(hwnd, &pt);
HBRUSH hBrush = CreateSolidBrush(RGB(,,));
SelectObject(hdc, hBrush);
Rectangle(hdc, , , cx/, cy/);
DeleteObject(hBrush);
EndPaint(hwnd, &pt);
return ;
case WM_DESTROY:
PostQuitMessage();
return ;
default:
break;
} return DefWindowProc(hwnd, message, wParam, lParam);
} LRESULT CALLBACK MyProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
static int cx, cy; switch (message)
{
case WM_SIZE:
cx = LOWORD(lParam);
cy = HIWORD(lParam);
break;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
HBRUSH hBrush = CreateSolidBrush(RGB(, , ));
SelectObject(hdc, hBrush);
Rectangle(hdc, cx / , cy / , cx, cy);
DeleteObject(hBrush);
EndPaint(hwnd, &ps);
break;
default:
break;
}
return WindProc(hwnd, message, wParam, lParam);
}
运行结果
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