Editing listview subitems using LVM_GETEDITCONTROL

 

This artical suggests yet another way to edit subitems in CListView or CListCtrl. It uses LVM_GETEDITCONTROL message to return the handle of the actual edit control used by MFC and then subclasses the handle in order to re-postition the control over the subitem you wish to edit. The sample download program was written using MSVC 5.0 and includes a class called CListEditView, derived from CListView. The code can be modified to use CListCtrl as well. CListEditView::DrawItem(LPDRAWITEMSTRUCT lpDIS) is the slightly modified version taken from the ROWLIST example provided by MSVC 5.0. To use CListEditView in your project, just include the source and header files, and derive your list view class from CListEditView. Please feel free to modify the code as you see fit. Basically, it works as follows: When the handler for LVN_BEGINLABELEDIT is called, the handler locates the subitem from the current mouse position. It then retrieves the handle to the edit control, subclasses the control to a CEdit object and repositions the control over the location of the subitem. The subclassed CEdit object has the ON_WM_WINDOWPOSCHANGING handler overridden to use the coordinates of location of the subitem because it will try to reposition itself over the LABEL of the listview, when it becomes visible. When finished editing, the LVN_ENDLABELEDIT handler is called and if the operation was not aborted (by pressing ESC for example), the handler sets the subitem text to the contents in the edit control. I've included the source code for these two handlers below.

void CListEditView::OnBeginLabelEdit(NMHDR* pNMHDR,LRESULT* pResult) 
{
    LV_DISPINFO* pDispInfo=(LV_DISPINFO*)pNMHDR;

    *pResult=1;
	
    CPoint posMouse;
    GetCursorPos(&posMouse);
    ScreenToClient(&posMouse);

    LV_COLUMN lvc;
    lvc.mask=LVCF_WIDTH;

    CRect rcItem;
    GetListCtrl().GetItemRect(pDispInfo->item.iItem,rcItem,LVIR_LABEL);

    if(rcItem.PtInRect(posMouse))
        m_nEdit=0;	

    int nCol=1;
    while(m_nEdit==-1 && GetListCtrl().GetColumn(nCol,&lvc))
    {	
        rcItem.left=rcItem.right;
        rcItem.right+=lvc.cx;

        if(rcItem.PtInRect(posMouse))
            m_nEdit=nCol;	

        nCol++;	
    }

    if(m_nEdit==-1)
        return;
			
    HWND hWnd=(HWND)SendMessage(LVM_GETEDITCONTROL);
    ASSERT(hWnd!=NULL);
    VERIFY(m_LVEdit.SubclassWindow(hWnd));

    m_LVEdit.m_x=rcItem.left;
    m_LVEdit.m_y=rcItem.top-1;

    m_LVEdit.SetWindowText(GetListCtrl().GetItemText(pDispInfo->item.iItem,m_nEdit));

    *pResult=0;
}

void CListEditView::OnEndLabelEdit(NMHDR* pNMHDR, LRESULT* pResult) 
{
    LV_DISPINFO* pDispInfo=(LV_DISPINFO*)pNMHDR;

    CString sEdit=pDispInfo->item.pszText;

    if(!sEdit.IsEmpty())
    {
      GetListCtrl().SetItemText(pDispInfo->item.iItem,m_nEdit,sEdit);
    }

    m_nEdit=-1;

    VERIFY(m_LVEdit.UnsubclassWindow()!=NULL);

    GetListCtrl().SetItemState(pDispInfo->item.iItem,0,LVNI_FOCUSED|LVNI_SELECTED);

    *pResult=0;
}

Download demo project - 42 KB

Download source - 4 KB



Comments

Leave a Comment
  • Your email address will not be published. All fields are required.

Top White Papers and Webcasts

  • Live Event Date: August 20, 2014 @ 1:00 p.m. ET / 10:00 a.m. PT When you look at natural user interfaces as a developer, it isn't just fun and games. There are some very serious, real-world usage models of how things can help make the world a better place – things like Intel® RealSense™ technology. Check out this upcoming eSeminar and join the panel of experts, both from inside and outside of Intel, as they discuss how natural user interfaces will likely be getting adopted in a wide variety …

  • Protecting business operations means shifting the priorities around availability from disaster recovery to business continuity. Enterprises are shifting their focus from recovery from a disaster to preventing the disaster in the first place. With this change in mindset, disaster recovery is no longer the first line of defense; the organizations with a smarter business continuity practice are less impacted when disasters strike. This SmartSelect will provide insight to help guide your enterprise toward better …

Most Popular Programming Stories

More for Developers

Latest Developer Headlines

RSS Feeds