스크롤 바 (scrollbar, EnableScrollBar, ESB_DISABLE_LEFT, SetScrollRange, SetScrollPos, SB_THUMBTRACK)

#include <windows.h>

LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
HINSTANCE g_hInst;
LPSTR lpszClass="ScrCtl";

int APIENTRY WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance
         ,LPSTR lpszCmdParam,int nCmdShow)
{
    HWND hWnd;
    MSG Message;
    WNDCLASS WndClass;
    g_hInst=hInstance;
    
    WndClass.cbClsExtra=0;
    WndClass.cbWndExtra=0;
    WndClass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);
    WndClass.hCursor=LoadCursor(NULL,IDC_ARROW);
    WndClass.hIcon=LoadIcon(NULL,IDI_APPLICATION);
    WndClass.hInstance=hInstance;
    WndClass.lpfnWndProc=(WNDPROC)WndProc;
    WndClass.lpszClassName=lpszClass;
    WndClass.lpszMenuName=NULL;
    WndClass.style=CS_HREDRAW | CS_VREDRAW;
    RegisterClass(&WndClass);

    hWnd=CreateWindow(lpszClass,lpszClass,WS_OVERLAPPEDWINDOW |
        WS_CLIPCHILDREN,
        CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,
        NULL,(HMENU)NULL,hInstance,NULL);
    ShowWindow(hWnd,nCmdShow);
    
    while(GetMessage(&Message,0,0,0)) {
        TranslateMessage(&Message);
        DispatchMessage(&Message);
    }
    return Message.wParam;
}

#define ID_SCROLL 100
HWND hScroll;
int Value;
LRESULT CALLBACK WndProc(HWND hWnd,UINT iMessage,WPARAM wParam,LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    char str[128];
    switch(iMessage) {
    case WM_CREATE:
        hScroll=CreateWindow("scrollbar",NULL,WS_CHILD | WS_VISIBLE | SBS_HORZ,
            10,100,200,20,hWnd,(HMENU)ID_SCROLL,g_hInst,NULL);
        Value=50;
        SetScrollRange(hScroll,SB_CTL,0,100,TRUE);    // 스크롤바 값 범위 설정
        SetScrollPos(hScroll,SB_CTL,Value,TRUE);    // 현재 위치 설정
        return 0;
    case WM_HSCROLL:
        switch (LOWORD(wParam)) {
        case SB_LINELEFT:
            Value=max(0,Value-1);
            break;
        case SB_LINERIGHT:
            Value=min(100,Value+1);
            break;
        case SB_PAGELEFT:
            Value=max(0,Value-10);
            break;
        case SB_PAGERIGHT:
            Value=min(100,Value+10);
            break;
        case SB_THUMBTRACK:
            Value=HIWORD(wParam);
            break;
        }
        SetScrollPos((HWND)lParam,SB_CTL,Value,TRUE);
        InvalidateRect(hWnd,NULL,TRUE);
        return 0;
    case WM_LBUTTONDOWN:
        EnableScrollBar(hScroll,SB_CTL,ESB_DISABLE_LEFT);    // 스크롤바 버튼 비활성화
        return 0;
    case WM_RBUTTONDOWN:
        EnableScrollBar(hScroll,SB_CTL,ESB_ENABLE_BOTH);    // 활성화
        return 0;
    case WM_PAINT:
        hdc=BeginPaint(hWnd, &ps);
        wsprintf(str,"Value is %d",Value);
        TextOut(hdc,50,50,str,strlen(str));
        EndPaint(hWnd, &ps);
        return 0;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return(DefWindowProc(hWnd,iMessage,wParam,lParam));
}