Question

基本上我有一个可以携带其他控件的自定义窗口，比方说按钮，位图，文本框等等，现在问题是，如果项目出窗外，我的意思是如果我试图创建像20个按钮明显它会离开窗口，所以我想我应该创建一个滚动条，使窗口滚动。很明显你不能添加WS_VSCROLL或WS_HSCROLL，因为它的向上和向下箭头都不会被点击，但如果你试图拖动它，它会跳回到顶部。所以我想我最好用createwindow（）函数创建一个滚动条并控制剩下的东西。

以下是我如何创建窗口本身和滚动条的代码：代码：

BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
hInst = hInstance; // Store instance handle in our global variable

hWnd = CreateWindow(szWindowClass, "Name", WS_OVERLAPPEDWINDOW/*WS_OVERLAPPED | WS_MINIMIZEBOX | WS_SYSMENU*/,
  CW_USEDEFAULT, 0, 1014, 585, NULL, NULL, hInstance, NULL);

 if (!hWnd)
{
  return FALSE;
}

WNDCLASSEX wcs;

wcs.cbSize          = sizeof(wcs);
wcs.lpszClassName   = szClassName;
wcs.hInstance       = GetModuleHandle(0);
wcs.lpfnWndProc     = CustWndProc;
wcs.hCursor         = LoadCursor(NULL, IDC_ARROW);
wcs.hIcon           = 0;
wcs.lpszMenuName        = 0;
wcs.hbrBackground   = (HBRUSH)(COLOR_WINDOW+1);
wcs.style           = 0;
wcs.cbClsExtra      = 0;
wcs.cbWndExtra      = 0;
wcs.hIconSm         = 0;

if(!RegisterClassEx(&wcs))
{
    MessageBox(NULL, "Window Registration Failed!", "Error!",
        MB_ICONEXCLAMATION | MB_OK);
    return 0;
}

hwndCtrl = CreateWindowEx(
                     0L, // give it a standard border
                     szClassName,
                     _T("A custom control"),
                     WS_VISIBLE|WS_CHILD|WS_BORDER,
                     0, 0, 0, 0,
                     hWnd,
                     NULL, GetModuleHandle(0), CustWndProc
                   );
ShowWindow (hwndCtrl, SW_SHOW);
ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);

return TRUE;
}

这是处理其消息的代码：

LRESULT CALLBACK CustWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
UNREFERENCED_PARAMETER(lParam);
RECT rc = {};
GetClientRect(hwnd, &rc);
const SIZE sz = { rc.right - rc.left, rc.bottom - rc.top };
SCROLLINFO si;

switch(msg)
{
    case WM_MOUSEHOVER: 
        ::MessageBox(hwnd, "Enter", "Info", MB_OK); 

        return 0; 
case WM_CREATE:
    int w , h;
    w = 10;
    h = 10;
    HWND buttons;
    for(h=10;h<500; h+=35){
        buttons = CreateWindow("BUTTON", "How", WS_VISIBLE|WS_CHILD, w, h, 50, 30, hwnd, (HMENU)1231,NULL, NULL);
    }
    int width, height;
    width           = LOWORD(lParam);                                                   // Width Size of hWnd
    height          = HIWORD(lParam);
    Scrollbar  = CreateWindowEx(0L,
                   "SCROLLBAR",
                   NULL, // There is no text to display
                   WS_CHILD | WS_VISIBLE | SBS_VERT,
                   980,
                   47,
                   18,
                   405,
                   hWnd,
                   NULL,
                   hInst,
                   NULL
                );
    return 0;
case WM_INITDIALOG:
    ZeroMemory(&si, sizeof(si));
    si.cbSize = sizeof(si);
    si.fMask  = SIF_RANGE | SIF_PAGE | SIF_POS;
    si.nMin   = 0;
    si.nMax   = 1000;
    si.nPage  = 10;
    si.nPos   = 54;
    SetScrollInfo(Scrollbar, SB_CTL, &si, TRUE);
    return TRUE;


default:
    return DefWindowProc(hwnd, msg, wParam, lParam);
}
return FALSE;
}

正如你所看到的那样，有一些按钮是用for循环自动创建的，之后滚动条本身正在创建，现在我不知道如何让它向下和向上滚动等等。欢迎所有回复

Answer 1

一个快速而又肮脏的例子：

case WM_VSCROLL:
{
    auto action = LOWORD(wParam);
    HWND hScroll = (HWND)lParam;
    int pos = -1;
    if (action == SB_THUMBPOSITION || action == SB_THUMBTRACK) {
        pos = HIWORD(wParam);
    } else if (action == SB_LINEDOWN) {
        pos = g_scrollY + 30;
    } else if (action == SB_LINEUP) {
        pos = g_scrollY - 30;
    } 
    if (pos == -1)
        break;
    WCHAR buf[20];
    SCROLLINFO si = { 0 };
    si.cbSize = sizeof(SCROLLINFO);
    si.fMask = SIF_POS;
    si.nPos = pos;
    si.nTrackPos = 0;
    SetScrollInfo(hWnd, SB_VERT, &si, true);
    GetScrollInfo(hWnd, SB_VERT, &si);
    pos = si.nPos;
    POINT pt;
    pt.x = 0;
    pt.y = pos - g_scrollY;
    auto hdc = GetDC(hWnd);
    LPtoDP(hdc, &pt, 1);
    ReleaseDC(hWnd, hdc);
    ScrollWindow(hWnd, 0, -pt.y, NULL, NULL);
    g_scrollY = pos;
    return 0;
}
case WM_CREATE:
{
    for (int i = 0; i < 100; ++i) {
        auto hEdit = CreateWindowEx(WS_EX_CLIENTEDGE, L"EDIT", L"",
            WS_CHILD | WS_VISIBLE | ES_AUTOHSCROLL, 10, 30 * i, 250, 21, hWnd, NULL, hInst, NULL);
        wchar_t buf[10];
        StringCchPrintf(buf, 10, L"%d", i);
        SetWindowText(hEdit, buf);
    }
    RECT rc = { 0 };
    GetClientRect(hWnd, &rc);
    SCROLLINFO si = { 0 };
    si.cbSize = sizeof(SCROLLINFO);
    si.fMask = SIF_ALL;
    si.nMin = 0;
    si.nMax = 30 * 99 + 21;
    si.nPage = (rc.bottom - rc.top);
    si.nPos = 0;
    si.nTrackPos = 0;
    SetScrollInfo(hWnd, SB_VERT, &si, true);
    return 0;
}

效果：

完整代码：http://pastebin.com/byE1xFsb

由于OP无法理解代码，这里有解释：

窗口的整个高度应为30 * 99 + 21. 99是编辑计数，21是编辑控件的高度。
窗口的滚动范围应为[0, 30 * 99 + 21 - client-area-height]。 30 * 99 + 21 - client-area-height + client-area-height等于30 * 99 + 21，这是窗口的整个高度。

要确保上述滚动范围，

si.nMax = 30 * 99 + 21;
si.nPage = (rc.bottom - rc.top);

Answer 2

以下是 Jichao 的改编代码，用于与孩子一起滚动静态。

// hStaticWnd should have WS_CLIPCHILDREN flag

#define WMU_SET_SCROLL_HEIGHT WM_USER + 100 // custom message
...
SetWindowLong(hStaticWnd, GWL_WNDPROC, (LONG)&cbNewScroll);
...
SendMessage(hColumnsWnd, WMU_SET_SCROLL_HEIGHT, 500, 0); 
...
SendMessage(hColumnsWnd, WMU_SET_SCROLL_HEIGHT, 0, 0); // to turn off the scroll

LRESULT CALLBACK cbNewScroll(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam) {
    switch (msg) {
        case WM_VSCROLL: {
            WORD action = LOWORD(wParam);
            int scrollY = (int)GetProp(hWnd, TEXT("SCROLLY"));

            int pos = action == SB_THUMBPOSITION ? HIWORD(wParam) :
                action == SB_THUMBTRACK ? HIWORD(wParam) :
                action == SB_LINEDOWN ? scrollY + 30 :
                action == SB_LINEUP ? scrollY - 30 :
                -1;

            if (pos == -1)
                break;

            SCROLLINFO si{0};
            si.cbSize = sizeof(SCROLLINFO);
            si.fMask = SIF_POS;
            si.nPos = pos;
            si.nTrackPos = 0;
            SetScrollInfo(hWnd, SB_VERT, &si, true);
            GetScrollInfo(hWnd, SB_VERT, &si);
            pos = si.nPos;
            POINT p{0, pos - scrollY};
            HDC hdc = GetDC(hWnd);
            LPtoDP(hdc, &p, 1);
            ReleaseDC(hWnd, hdc);
            ScrollWindow(hWnd, 0, -p.y, NULL, NULL);
            SetProp(hWnd, TEXT("SCROLLY"), (HANDLE)pos);

            return 0;
        }
        break;

        case WM_ERASEBKGND: {
            HDC hDC = (HDC)wParam;
            RECT rc{0};
            GetClientRect(hWnd, &rc);
            HBRUSH hBrush = CreateSolidBrush(GetSysColor(COLOR_BTNFACE));
            FillRect(hDC, &rc, hBrush);
            DeleteObject(hBrush);

            return 1;
        }
        break;

        case WMU_SET_SCROLL_HEIGHT: { 
            RECT rc = { 0 };
            GetWindowRect(hWnd, &rc);
            SCROLLINFO si = { 0 };
            si.cbSize = sizeof(SCROLLINFO);
            si.fMask = SIF_ALL;
            si.nMin = 0;
            si.nMax = wParam;
            si.nPage = rc.bottom - rc.top;
            si.nPos = 0;
            si.nTrackPos = 0;

            SetScrollInfo(hWnd, SB_VERT, &si, true);
        }
        break;

        case WM_DESTROY: {
            RemoveProp(hWnd, TEXT("SCROLLY"));
        }
        break;
    }


    return CallWindowProc(DefWindowProc, hWnd, msg, wParam, lParam);
}

Answer 3

这里有一个example from microsot，它可以处理文本，但是可以很容易地将其适应固定高度的组件。而本文how-to-control-scrollbar-in-vc-win32-api恰好符合问题的要求，并且代码清晰易读。

Answer 4

我知道现在已经晚了5年，但是如果有人来找，我认为至少对OP的第二个问题有一个答案是很高兴的（因为Jichao回答了原始问题）。

哦，男孩不敢相信这几乎行不通，仍然有一些问题就像滚动有一个限制。我的意思是它可以显示约50 或某行即使我没有那么多项目，也没有，我知道问题是si.nMax = 30 * 99 + 21;告诉它限制为30 * 99 + 21，但是必须有一些东西必须花很多钱才能使用窗口行，并且只显示那么多。

因此，窗口的早期截止实际上是由于“ GetClientRect（hWnd，＆rc）;”造成的。我在自己的项目中发现将其更改为“ GetWindowRect（hWnd，＆rc）;”。并在创建（或调整大小）窗口后设置RECT解决了该问题。

//Called after Window Creation (not in WM_Create! After CreateWindowEx called!) or during Resize.
void ResetScrollbarSize(HWND hWnd)
{
    RECT rc = { 0 };
    GetWindowRect(hWnd, &rc);
    SCROLLINFO si = { 0 };
    si.cbSize = sizeof(SCROLLINFO);
    si.fMask = SIF_ALL;
    si.nMin = 0;
    si.nMax = 30 * 99 + 21;
    si.nPage = (rc.bottom - rc.top);
    si.nPos = 0;
    si.nTrackPos = 0;
    SetScrollInfo(hWnd, SB_VERT, &si, true);
}

该功能可以解决问题。同样，调用并完成了在 CreateWindowEx之后使用它的重要部分，因此Window需要获取RECT。

如何在vc ++ win32 api

4 个答案: