问题描述

MFC CListCtrl类checkbox问题

MFC项目用到CListCtrl控件，CListCtrl控件的view设置为list，而且style含有LVS_EX_CHECKBOXES，即每一行最前面都有一个checkbox，那么问题来了，我在勾选和取消checkbox时，怎么捕获checkbox的change消息

解决方案

void CStatusBarDlg::OnClickStateList(NMHDR* pNMHDR, LRESULT* pResult)
{
    DWORD dwPos = GetMessagePos();
    CPoint point( LOWORD(dwPos), HIWORD(dwPos) );  

    m_StatusList.ScreenToClient(&point);  

    LVHITTESTINFO lvinfo;
    lvinfo.pt = point;
    lvinfo.flags = LVHT_ABOVE;  

    UINT nFlag;
    int nItem = m_StatusList.HitTest(point, &nFlag);
    //判断是否点在checkbox上
    if(nFlag == LVHT_ONITEMSTATEICON)
    {
        TRACE("You click CheckBox,Item will be Clicked!");
        }
    *pResult = 0;
}

解决方案二：

响应LVN_ITEMCHANGED这个消息，下面是一段示例代码

LPNMLISTVIEW pNMLV = reinterpret_cast(pNMHDR);
*pResult = 0;
CManageBillDoc *pDoc = GetDocument();
POSITION pos = m_DataList.GetFirstSelectedItemPosition();
while(pos)
{
int nItem = m_DataList.GetNextSelectedItem(pos);
pDoc->m_nSelectItemID = (long)m_DataList.GetItemData(nItem);

}

if(pNMLV->uOldState == 0 && pNMLV->uNewState == 0)//行CheckBox状态没有变化
{
    return;
}

//原始状态
BOOL bPrevState = (BOOL)(((pNMLV->uOldState & LVIS_STATEIMAGEMASK) >> 12) - 1);
if(bPrevState < 0)//控件刚刚创建，没有原始状态
{
    bPrevState = 0;//就可以认为本项原始状态是未选中的状态
}

//新状态
BOOL bNewState = (BOOL)(((pNMLV->uNewState & LVIS_STATEIMAGEMASK) >> 12) - 1);
if(bNewState < 0)//没有LVS_EX_CHECKBOX状态的ListCtrl
{
    bNewState = 0;
}

if(bNewState == bPrevState)//checkbox状态没有改变
    return;
else if(bNewState)
{
    //........
}