C / C++ / MFC

Joe Woodbury wrote:

As I said to Ravi, I think I'll have to superclass the window and handle WM_SIZE BEFORE the control gets it.

DWORD style = GetWindowLong(m_hWnd, GWL_STYLE);<br />
int scrollWidth = (style & WS_VSCROLL) ? ::GetSystemMetrics(SM_CXVSCROLL) - 2 : 2;<br />
<br />
CRect rect;<br />
m_listCtrl.GetClientRect(rect);<br />
m_listCtrl.SetColumnWidth(CSpyListCtrl::DATA_COLUMN, rect.right - CSpyListCtrl::TIME_COLUMN_WIDTH - CSpyListCtrl::TOPIC_COLUMN_WIDTH - scrollWidth);

Joe Woodbury wrote:

Ah, it doesn't show up for no reason. It shows up when resizing and during that resizing operation the column width is momentarily bigger that the size of the window BEFORE its adjusted.

#include "stdafx.h"
#include "MFCTester.h"
#include "TestListViewDialog.h"
#include ".\testlistviewdialog.h"
 
 
// CTestListViewDialog dialog
 
IMPLEMENT_DYNAMIC(CTestListViewDialog, CDialog)
CTestListViewDialog::CTestListViewDialog(CWnd* pParent /*=NULL*/)
   : CDialog(CTestListViewDialog::IDD, pParent)
{
}
 
CTestListViewDialog::~CTestListViewDialog()
{
}
 
void CTestListViewDialog::DoDataExchange(CDataExchange* pDX)
{
   CDialog::DoDataExchange(pDX);
   DDX_Control(pDX, IDC_LIST1, m_ListCtrl);
}
 
 
BEGIN_MESSAGE_MAP(CTestListViewDialog, CDialog)
   ON_WM_SIZING()
   ON_WM_SIZE()
   ON_WM_ERASEBKGND()
END_MESSAGE_MAP()
 
 
// CTestListViewDialog message handlers
 
BOOL CTestListViewDialog::OnInitDialog()
{
   CDialog::OnInitDialog();
 
   UpdateData(FALSE);
 
   m_ListCtrl.InsertColumn(0, _T("Column 1"));
   m_ListCtrl.InsertColumn(1, _T("Column 2"));
 
   m_ListCtrl.SetExtendedStyle(m_ListCtrl.GetExtendedStyle() | LVS_EX_GRIDLINES);
 
   FitListViewToDialog();
 
   return TRUE;
}
 
void CTestListViewDialog::OnSizing(UINT fwSide, LPRECT pRect)
{
   CDialog::OnSizing(fwSide, pRect);
 
   if (pRect->right - pRect->left < 320)
      pRect->right = pRect->left + 320;
 
   if (pRect->bottom - pRect->top < 240)
      pRect->bottom = pRect->top + 240;
 
}
 
void CTestListViewDialog::OnSize(UINT nType, int cx, int cy)
{
   CDialog::OnSize(nType, cx, cy);
 
   if (cx > 0 && cy > 0)
   {
      FitListViewToDialog();
   }
}
 
void CTestListViewDialog::FitListViewToDialog()
{
   if (::IsWindow(m_ListCtrl))
   {
      CRect ClientRect;
      GetClientRect(&ClientRect);
 
      m_ListCtrl.MoveWindow(0, 0, ClientRect.Width(), ClientRect.Height(), TRUE);
 
      m_ListCtrl.SetColumnWidth(0, ClientRect.Width() / 2);
      m_ListCtrl.SetColumnWidth(1, LVSCW_AUTOSIZE_USEHEADER);
   }
}
 
BOOL CTestListViewDialog::OnEraseBkgnd(CDC* pDC)
{
   //return CDialog::OnEraseBkgnd(pDC);
   return TRUE;
}

#pragma once
#include "afxcmn.h"
 
// CTestListViewDialog dialog
 
class CTestListViewDialog : public CDialog
{
   DECLARE_DYNAMIC(CTestListViewDialog)
 
public:
   CTestListViewDialog(CWnd* pParent = NULL);   // standard constructor
   virtual ~CTestListViewDialog();
 
// Dialog Data
   enum { IDD = IDD_DIALOG1 };
 
protected:
   virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
 
   void FitListViewToDialog();
 
   DECLARE_MESSAGE_MAP()
public:
   virtual BOOL OnInitDialog();
   afx_msg void OnSizing(UINT fwSide, LPRECT pRect);
   afx_msg void OnSize(UINT nType, int cx, int cy);
   CListCtrl m_ListCtrl;
   afx_msg BOOL OnEraseBkgnd(CDC* pDC);
};

Mark Salsbery wrote:

The only way I can get the scrollbar to appear is if I force it by "incorrectly" calculating
column sizes (ie making the width of all columns greater than the control width).

Joe Woodbury wrote:

What I'm still seeing (and have observed this for years with other projects) is the horizontal scroll bar flashing when you resize a dialog smaller very quickly.

Mark Salsbery wrote:

Are you absolutely sure you're (intentionally or not) not redrawing the control before
resizing the columns - even in a seemingly unrelated message handler somewhere?

for (int i=0; (i < 10); i++) {
  Sleep (1000);
  int nIndex = m_listCtrl.InsertItem (i, "Hello");
  m_listCtrl.EnsureVisible (nIndex, TRUE);
  m_listCtrl.UpdateWindow();
}