window won't bounce

I am writting a code in which the window is supposed to bounce on the screen from top to bottom and left to right as soon as the user clicks the left botton in the client area, but its getting stuck as soon as it reaches the bottom. Help..

Code:

#include <windows.h> #include <tchar.h> #include <stdio.h> #include<time.h> #undef WS_OVERLAPPEDWINDOW #define WS_OVERLAPPEDWINDOW (WS_OVERLAPPED | \ WS_SYSMENU | \ WS_THICKFRAME ) LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ; int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) { static TCHAR szAppName[] = TEXT ("Connect") ; HWND hwnd ; MSG msg ; WNDCLASS wndclass ; wndclass.style = WS_EX_DLGMODALFRAME ; 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 ; } hwnd = CreateWindow (szAppName, TEXT ("C"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 100, 100, 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) { TCHAR s[100]; static int iCount ; HDC hdc ; int i, j, x, y, sx = 1, sy = 1, bottom, right, top, left ; PAINTSTRUCT ps ; RECT r,win; top = left = 0; right = GetSystemMetrics(SM_CXSCREEN) - 100; bottom = GetSystemMetrics(SM_CYSCREEN) - 100; switch (message) { case WM_LBUTTONDOWN: srand(time(NULL)); GetWindowRect(hwnd,&r); while(1) { x = rand() % 5 + 1; y = rand() % 5 + 1; while((r.bottom < bottom) && (r.right < right) && (r.top > top) && (r.left > left)) { r.left += (x*sx); r.top += (y*sy); MoveWindow(hwnd,r.left,r.top,100,100, TRUE); GetWindowRect(hwnd,&r); } if(r.bottom>= bottom) sy = -1; else if(r.right>= right) sx = -1; else if(r.top <= top) sy = 1; else if(r.left<=left) sx = 1; } return 0; case WM_PAINT: hdc = BeginPaint(hwnd, &ps); TextOut (hdc, 0, 0, TEXT("Click Me"),4) ; EndPaint(hwnd, &ps); return 0; case WM_DESTROY: PostQuitMessage (0) ; return 0 ; } return DefWindowProc (hwnd, message, wParam, lParam) ; }

> while(1)
Well it's not going anywhere after it gets into this loop.

IIRC, you're going to get a whole series of WM_LBUTTONDOWN messages, so try just moving a few pixels and then exiting the wndproc

> srand(time(NULL));
This you do ONCE when the program starts.

Quote:

Originally Posted by Salem

so try just moving a few pixels and then exiting the wndproc

Am not being lazy, but how is that done??

I tried this such that the window gets displaced when the mouse pointer is brought on the client area, but the same problem exists..

Code:

#include <windows.h> #include <tchar.h> #include <stdio.h> #include<time.h> #undef WS_OVERLAPPEDWINDOW #define WS_OVERLAPPEDWINDOW (WS_OVERLAPPED | \ WS_SYSMENU | \ WS_THICKFRAME ) LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ; int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) { static TCHAR szAppName[] = TEXT ("Connect") ; HWND hwnd ; MSG msg ; WNDCLASS wndclass ; wndclass.style = WS_EX_DLGMODALFRAME ; 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 ; } hwnd = CreateWindow (szAppName, TEXT ("C"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 100, 100, NULL, NULL, hInstance, NULL) ; ShowWindow (hwnd, iCmdShow) ; UpdateWindow (hwnd) ; srand(time(NULL)); while (GetMessage (&msg, NULL, 0, 0)) { TranslateMessage (&msg) ; DispatchMessage (&msg) ; } return msg.wParam ; } LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) { TCHAR s[100]; static int iCount,bottom, right, top, left, sx = 1, sy = 1 ; HDC hdc ; int i, j, x, y; PAINTSTRUCT ps ; RECT r,win; top = left = 0; right = GetSystemMetrics(SM_CXSCREEN) - 100; bottom = GetSystemMetrics(SM_CYSCREEN) - 100; switch (message) { case WM_LBUTTONDOWN: GetWindowRect(hwnd,&r); x = rand() % 5 + 1; y = rand() % 5 + 1; while((r.bottom < bottom) && (r.right < right) && (r.top > top) && (r.left > left)) { r.left += (x*sx); r.top += (y*sy); MoveWindow(hwnd,r.left,r.top,100,100, TRUE); GetWindowRect(hwnd,&r); } if(r.bottom>= bottom) sy = -1; else if(r.right>= right) sx = -1; else if(r.top <= top) sy = 1; else if(r.left<=left) sx = 1; return 0; case WM_MOUSEMOVE: SendMessage(hwnd, WM_LBUTTONDOWN,wParam,lParam); return 0; case WM_PAINT: hdc = BeginPaint(hwnd, &ps); TextOut (hdc, 0, 0, TEXT("Click Me"),8) ; EndPaint(hwnd, &ps); return 0; case WM_DESTROY: PostQuitMessage (0) ; return 0 ; } return DefWindowProc (hwnd, message, wParam, lParam) ; }

Is there some way to debug a windows program line by line, by stepping into the WndProc, just like we do in the console programs?

> while((r.bottom < bottom) && (r.right < right) && (r.top > top) && (r.left > left))
Change this to an if statement as well.

Is there some way to debug a windows program line by line, by stepping into the WndProc, just like we do in the console programs?

Quote:

Originally Posted by juice

Is there some way to debug a windows program line by line, by stepping into the WndProc, just like we do in the console programs?

What IDE are you using?

Cheap animation can be created with a timer. I have 4 of your little windows bouncing around my screen right now.

Code:

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) { static int bottom, right, sx = 1, sy = 1, x, y; static BOOL timerOn = FALSE; HDC hdc ; PAINTSTRUCT ps ; RECT r; switch (message) { case WM_CREATE: right = GetSystemMetrics(SM_CXSCREEN) - 10; bottom = GetSystemMetrics(SM_CYSCREEN) - 10; return 0; case WM_TIMER: GetWindowRect(hwnd, &r); if (r.bottom >= bottom) sy = -1; else if (r.top <= 0 ) sy = 1; if (r.right >= right) sx = -1; else if (r.left <= 0 ) sx = 1; r.left += x * sx; r.top += y * sy; MoveWindow(hwnd, r.left, r.top, 100, 100, TRUE); return 0; case WM_LBUTTONDOWN: if (timerOn) { KillTimer(hwnd, 1); timerOn = FALSE; return 0; } x = rand() % 10 + 5; y = rand() % 10 + 5; sx = rand() % 2 ? 1 : -1; sy = rand() % 2 ? 1 : -1; SetTimer(hwnd, 1, 50, 0); timerOn = TRUE; return 0;

Quote:

Originally Posted by oogabooga

what ide are you using?

msvc 2010

>>Is there some way to debug a windows program line by line, by stepping into the WndProc, just like we do in the console programs?

Set a break point (F9) on the line you want to debug (ie in the LB down) and run/start [can not be a 'release' build but MSVC builds 'debug' by default].

When the line of code is hit the app will pause. Use F10 to step line by line. F11 to step into functions. F5 to run to next break point.

Beware of setting break points in things like paint, which would generate a paint msg, which would generate a paint msg, which would generate a paint msg, which would generate a paint msg (ie infinite loop)