Preventing certain Listview columns from sizing...

[sergelac]

there is a big problem with the column width version

if you resize a unlocked column to the specified size (0), it will become locked



i use a ParamArray to specify the column numbers so i can use it on all my forms

SubClassHwnd ListView1.hWnd, 7, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23

Option Explicit
Option Base 0

' GetWindowsLong Constants
Private Const GWL_WNDPROC = (-4)

' Windows Message Constants
Private Const WM_NOTIFY = &H4E
Private Const WM_DESTROY = &H2

' Column Header Notification Meassage Constants
Private Const HDN_FIRST = -300&
Private Const HDN_DIVIDERDBLCLICKA = (HDN_FIRST - 5)
Private Const HDN_BEGINTRACK = (HDN_FIRST - 6)

' Column Header Item Info Message Constants
Private Const HDI_WIDTH = &H1

' Notify Message Header Type
Private Type NMHDR
   hWndFrom As Long
   idFrom As Long
   code As Long
End Type

' Notify Message Header for Listview
Private Type NMHEADER
     hdr As NMHDR
     iItem As Long
     iButton As Long
     lPtrHDItem As Long ' HDITEM FAR* pItem
End Type

' Header Item Type
Private Type HDITEM
    mask As Long
    cxy As Long
    pszText As Long
    hbm As Long
    cchTextMax As Long
    fmt As Long
    lParam As Long
    iImage As Long
    iOrder As Long
End Type

Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal hWnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)

Private mlPrevWndProc As Long, ColumnsBits As Long

Private Function WindowProc(ByVal hWnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    Dim tNMH As NMHDR
    Dim tNMHEADER As NMHEADER
    Dim tITEM As HDITEM
    
    Select Case Msg
    Case WM_NOTIFY
        ' Copy the Notify Message Header to a Header Structure
        CopyMemory tNMH, ByVal lParam, Len(tNMH)

        Select Case tNMH.code
        Case HDN_DIVIDERDBLCLICKA
            ' If the user is trying to DOUBLECLICK a Column Header
            ' Extract Information about the Header being Sized
            CopyMemory tNMHEADER, ByVal lParam, Len(tNMHEADER)

            ' Don't allow Columns to be Sized.
            If (ColumnsBits And (2 ^ tNMHEADER.iItem)) = (2 ^ tNMHEADER.iItem) Then
                WindowProc = 1
                Exit Function
            End If
        Case HDN_BEGINTRACK
            ' If the user is trying to Size a Column Header
            ' Extract Information about the Header being Sized
            CopyMemory tNMHEADER, ByVal lParam, Len(tNMHEADER)

            ' Don't allow Columns to be Sized.
            If (ColumnsBits And (2 ^ tNMHEADER.iItem)) = (2 ^ tNMHEADER.iItem) Then
                WindowProc = 1
                Exit Function
            End If
        End Select

    Case WM_DESTROY
        ' Remove Subclassing when Listview is Destroyed (Form unloaded)
        WindowProc = CallWindowProc(mlPrevWndProc, hWnd, Msg, wParam, lParam)
        Call SetWindowLong(hWnd, GWL_WNDPROC, mlPrevWndProc)
        Exit Function
    End Select

    ' Call Default Window Handler
    WindowProc = CallWindowProc(mlPrevWndProc, hWnd, Msg, wParam, lParam)
End Function

Public Sub SubClassHwnd(ByVal hWnd As Long, ParamArray ColumnsNums())
    Dim t As Integer
    ColumnsBits = 0
    For t = 0 To UBound(ColumnsNums)
      ColumnsBits = ColumnsBits + (2 ^ (ColumnsNums(t) - 1))
    Next t
    mlPrevWndProc = SetWindowLong(hWnd, GWL_WNDPROC, AddressOf WindowProc)
End Sub

optionaly you can move all the hidden column to the left

ListView1.ColumnHeaders(7).Position = 1