子窗口控件(4)之滚动条和静态子窗口的使用
滚动条类跟窗体滚动条差不多。
如果想创建和窗口具有相同尺寸的滚动条控件，则可以使用GetSystemMetrics获得水平滚动条的高度
GetSystemMetrics(SM_CYHSCROLL);
或获得垂直滚动条的宽度
GetSystemMetrics(SM_CXVSCROLL);
同样可以窗口滚动条函数来设置滚动条控件的范围和位置
SetScrollRange(hwndScroll,SB_CTL,iMin,iMax,bRedraw);SetScrollPos(hwndScroll,SB_CTL,iPos,bRedraw);SetScrollInfo(hwndScroll,SB_CTL,&si,bRedraw);
下面是一个具体的例子，来自Windows第五版。（程序很经典）
#include <windows.h>LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;LRESULT CALLBACK ScrollProc (HWND, UINT, WPARAM, LPARAM) ;int idFocus ;WNDPROC OldScroll[3] ;int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow){ static TCHAR szAppName[] = TEXT ("Colors1") ; 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 = CreateSolidBrush (0) ; 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 ("Color Scroll"), 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 COLORREF crPrim[3] = { RGB (255, 0, 0), RGB (0, 255, 0), RGB (0, 0, 255) } ; static HBRUSH hBrush[3], hBrushStatic ; static HWND hwndScroll[3], hwndLabel[3], hwndValue[3], hwndRect ; static int color[3], cyChar ; static RECT rcColor ; static TCHAR * szColorLabel[] = { TEXT ("Red"), TEXT ("Green"), TEXT ("Blue") } ; HINSTANCE hInstance ; int i, cxClient, cyClient ; TCHAR szBuffer[10] ; switch (message) { case WM_CREATE : hInstance = (HINSTANCE) GetWindowLong (hwnd, GWL_HINSTANCE) ; // 也可以在winMain函数前赋值给一个HINSTANCE全局变量 hwndRect = CreateWindow (TEXT ("static"), NULL, WS_CHILD | WS_VISIBLE | SS_WHITERECT,//Static Style,SS_CENTER也是这种类型 label 0, 0, 0, 0, hwnd, (HMENU) 9, hInstance, NULL) ; for (i = 0 ; i < 3 ; i++) { // The three scroll bars have IDs 0, 1, and 2, with // scroll bar ranges from 0 through 255. hwndScroll[i] = CreateWindow (TEXT ("scrollbar"), NULL, WS_CHILD | WS_VISIBLE | WS_TABSTOP | SBS_VERT,//WS_TABSTOP可以用tab键控制焦点，获取焦点会闪亮 0, 0, 0, 0, hwnd, (HMENU) i, hInstance, NULL) ; SetScrollRange (hwndScroll[i], SB_CTL, 0, 255, FALSE) ; SetScrollPos (hwndScroll[i], SB_CTL, 0, FALSE) ; // The three color-name labels have IDs 3, 4, and 5, // and text strings "Red", "Green", and "Blue". hwndLabel [i] = CreateWindow (TEXT ("static"), szColorLabel[i], WS_CHILD | WS_VISIBLE | SS_CENTER, 0, 0, 0, 0, hwnd, (HMENU) (i + 3), hInstance, NULL) ; // The three color-value text fields have IDs 6, 7, // and 8, and initial text strings of "0". hwndValue [i] = CreateWindow (TEXT ("static"), TEXT ("0"), WS_CHILD | WS_VISIBLE | SS_CENTER, 0, 0, 0, 0, hwnd, (HMENU) (i + 6), hInstance, NULL) ; OldScroll[i] = (WNDPROC) SetWindowLong (hwndScroll[i], GWL_WNDPROC, (LONG) ScrollProc) ; hBrush[i] = CreateSolidBrush (crPrim[i]) ; } hBrushStatic = CreateSolidBrush ( GetSysColor (COLOR_BTNHIGHLIGHT)) ; cyChar = HIWORD (GetDialogBaseUnits ()) ; return 0 ; case WM_SIZE : cxClient = LOWORD (lParam) ; cyClient = HIWORD (lParam) ; SetRect (&rcColor, cxClient / 2, 0, cxClient, cyClient) ; MoveWindow (hwndRect, 0, 0, cxClient / 2, cyClient, TRUE) ; for (i = 0 ; i < 3 ; i++) { MoveWindow (hwndScroll[i], (2 * i + 1) * cxClient / 14, 2 * cyChar, cxClient / 14, cyClient - 4 * cyChar, TRUE) ; MoveWindow (hwndLabel[i], (4 * i + 1) * cxClient / 28, cyChar / 2, cxClient / 7, cyChar, TRUE) ; MoveWindow (hwndValue[i], (4 * i + 1) * cxClient / 28, cyClient - 3 * cyChar / 2, cxClient / 7, cyChar, TRUE) ; } SetFocus (hwnd) ; return 0 ; case WM_SETFOCUS : SetFocus (hwndScroll[idFocus]) ; return 0 ; case WM_VSCROLL : i = GetWindowLong ((HWND) lParam, GWL_ID) ; switch (LOWORD (wParam))//低位wParam获取通知码 { case SB_PAGEDOWN : color[i] += 15 ; // fall through case SB_LINEDOWN : color[i] = min (255, color[i] + 1) ; break ; case SB_PAGEUP : color[i] -= 15 ; // fall through case SB_LINEUP : color[i] = max (0, color[i] - 1) ; break ; case SB_TOP : color[i] = 0 ; break ; case SB_BOTTOM : color[i] = 255 ; break ; case SB_THUMBPOSITION ://拖拽ed位置 case SB_THUMBTRACK ://拖拽ing位置 color[i] = HIWORD (wParam) ; break ; default : break ; } SetScrollPos (hwndScroll[i], SB_CTL, color[i], TRUE) ; wsprintf (szBuffer, TEXT ("%i"), color[i]) ; SetWindowText (hwndValue[i], szBuffer) ; DeleteObject ((HBRUSH) SetClassLong (hwnd, GCL_HBRBACKGROUND, (LONG) CreateSolidBrush (RGB (color[0], color[1], color[2])))) ; InvalidateRect (hwnd, &rcColor, TRUE) ; return 0 ; case WM_CTLCOLORSCROLLBAR : i = GetWindowLong ((HWND) lParam, GWL_ID) ; return (LRESULT) hBrush[i] ; case WM_CTLCOLORSTATIC : i = GetWindowLong ((HWND) lParam, GWL_ID) ; if (i >= 3 && i <= 8) // static text controls { SetTextColor ((HDC) wParam, crPrim[i % 3]) ; SetBkColor ((HDC) wParam, GetSysColor (COLOR_BTNHIGHLIGHT)); return (LRESULT) hBrushStatic ; } break ; case WM_SYSCOLORCHANGE : DeleteObject (hBrushStatic) ; hBrushStatic = CreateSolidBrush (GetSysColor (COLOR_BTNHIGHLIGHT)) ; return 0 ; case WM_DESTROY : DeleteObject ((HBRUSH) SetClassLong (hwnd, GCL_HBRBACKGROUND, (LONG) GetStockObject (WHITE_BRUSH))) ; for (i = 0 ; i < 3 ; i++) DeleteObject (hBrush[i]) ; DeleteObject (hBrushStatic) ; PostQuitMessage (0) ; return 0 ; } return DefWindowProc (hwnd, message, wParam, lParam) ;} LRESULT CALLBACK ScrollProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam){ int id = GetWindowLong (hwnd, GWL_ID) ; switch (message)//确定焦点，实现用tab键来转换焦点 { case WM_KEYDOWN : if (wParam == VK_TAB) SetFocus (GetDlgItem (GetParent (hwnd), (id + (GetKeyState (VK_SHIFT) < 0 ? 2 : 1)) % 3)) ; break ; case WM_SETFOCUS : idFocus = id ; break ; } return CallWindowProc (OldScroll[id], hwnd, message, wParam, lParam) ;}
运行结果如下
