如何确定是否显示CListCtrl的滚动条? [英] How to determine if a scrollbar for a CListCtrl is displaying?

问题描述

我有一个从CListCtrl派生的类.我希望所有列的宽度总计显示窗口的宽度，以免出现底部滚动条.我可以通过GetSystemMetrics(SM_CXVSCROLL)调用获取标准滚动条的宽度，但是我不知道如何确定垂直滚动条是否处于活动状态.我尝试使用:

I have a class that is derived from a CListCtrl. I want the widths of all the columns to total the width of the display Window, so that I don't get the bottom scrollbar. I can get the width of standard scrollbars vai the GetSystemMetrics(SM_CXVSCROLL) call, but I don't know how to tell if the vertical scrollbar is active. I've tried to use:

auto pScrollbar = GetScrollBarCtrl(SB_VERT);
auto is_visible = pScrollbar && pScrollbar->IsWindowVisible();

但是pScrollbar始终是nullptr.我四处张望，有些人说滚动条并不总是窗口，可能是手工绘制的(嗯！)，可能根本不是窗口.这会使我的生活更加困难.想法?

But pScrollbar is always a nullptr. I've looked around and some ppl are saying that the scrollbars are not always windows and may be draw in by hand (ugh!) and may not be a Window at all. This will make my life more difficult. Ideas?

推荐答案

来自我的链接问题(

From my linked question (How to stop the bottom scrollbar from a CListCtrl from displaying?), I was using:

void CMyListCtrl::ResizeLastColumn()
{
    LVCOLUMN column;
    column.mask = LVCF_WIDTH;
    LONG maxWidth = 0;
    for (int i = 0; i < lastColumnIndex; ++i)
    {
        GetColumn(i, &column);
        maxWidth += column.cx;
    }
    CRect wndRect;
    GetWindowRect(&wndRect);

    SetColumnWidth(lastColumnIndex, wndRect.Width() - maxWidth - 4);
}

将列的大小调整为客户区的宽度.事实证明，通过使用GetClientRect()代替，我不必减去-4或垂直滚动​​条宽度，这不再是问题.

to resize the columns to the width of the client area. Turns out, by using GetClientRect() instead, I don't have to subtract -4 or the vertical scrollbar width, making this no longer an issue.

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