An effective way to hide or show columns in list control dynamically

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Introduction

Recently, in one of my projects, I needed a CListCtrl derived class which has the ability to show/hide its columns dynamically. Using CListCtrl::DeleteColumn() is not a good idea because in that case the index of the sub items will be changed from time to time, thus assessing the sub items will become very complicated. I searched the Internet and did not find an existing solution for this. At last, I had to write my own class - CListCtrlEx to implement the feature.

The main features of CListCtrlEx

• Dynamically hide/show the columns.
• Provide a built-in context menu to select the columns and it is dynamically created based on the columns you insert.
• Drag-and-drop reorder columns (you must enable the LVS_EX_HEADERDRAGDROP style).
• Save/restore the columns' order, width and visibility in/from registry automatically.
• You do not need to change your existing code of CListCtrl derived classes. All you have to do is change their base class to CListCtrlEx.

Using the CListCtrlEx class

1. Add the following files to your project:
   • HeaderCtrlEx.h
   • HeaderCtrlEx.cpp
   • ListCtrlEx.h
   • ListCtrlEx.cpp
2. Import the following two cursor files into you resource and change their ID as mentioned in the square brackets:
   • res\VE_SPLIT.CUR [IDC_HEADER_OPEN]
   • res\VE_SIZEB.CUR [IDC_HEADER_SIZE]
3. Derive your own class, say CMyListCtrl, from CListCtrlEx.
4. Add a list control to your dialog in the resource editor and bind it to a member variable, say m_wndList. Of course the variable should be a CMyListCtrl object.

   void CTestListCtrlDlg::DoDataExchange(CDataExchange* pDX)
   {
       CDialog::DoDataExchange(pDX);
       DDX_Control(pDX, IDC_LIST, m_wndList);
   }

5. Save/restore the state of the columns.

   BOOL CTestListCtrlDlg::OnInitDialog()
   {
       CDialog::OnInitDialog();
   
       // Enable column drag & drop
       m_wndList.SetExtendedStyle(m_wndList.GetExtendedStyle() 
                                     | LVS_EX_HEADERDRAGDROP);
   
       // Insert columns and items to the list control here
   
       // Set the sub registry key to store the columns' state
       m_wndList.SetRegistryKey("MyListCtrl");
   
       // Restore the state of the columns
       m_wndList.RestoreState();
   }
   
   void CTestListCtrlDlg::OnDestroy()
   {
       CDialog::OnDestroy();
   
       // TODO: Add your message handler code here
   
       // Save the state of the columns
       m_wndList.SaveState();
   }

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)