Dalexan
asked on
Keeping Checkbox Style for Owner Drawn Listbox Control with Color Changing Items
I have the code downloaded and working that allows color changes within a listbox control (see below). The problem that I have is that I need to KEEP the checkboxes to the left of the items added within the control (the code changes the color of the string to the color number listed in the text portion). If you run the code, then the checkboxes go away. Is there a way to do this?
The code is listed below
create a project with a listbox control. Set the listbox style to Checkbox
Option Explicit
Private Sub Form_Load()
Dim I As Integer
For I = 0 To 15
'Load a List of 0 to 15 with the Item Data
'Set to the QBColors 0 - 15
List1.AddItem "Color " & I
List1.itemData(List1.NewIn dex) = QBColor(I)
Next
'Subclass the "Form", to Capture the Listbox Notification Messages
SubLists hwnd
End Sub
Private Sub Form_Unload(Cancel As Integer)
'Release the SubClassing, Very Import to Prevent Crashing!
RemoveSubLists hwnd
End Sub
Place the following code in a module:
Option Explicit
Public Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type
Public Type DRAWITEMSTRUCT
CtlType As Long
CtlID As Long
itemID As Long
itemAction As Long
itemState As Long
hwndItem As Long
hdc As Long
rcItem As RECT
itemData As Long
End Type
Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Public Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Public 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
Public Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Public Declare Function CreateSolidBrush Lib "gdi32" (ByVal crColor As Long) As Long
Public Declare Function FillRect Lib "user32" (ByVal hdc As Long, lpRect As RECT, ByVal hBrush As Long) As Long
Public Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long
Public Declare Function SetBkColor Lib "gdi32" (ByVal hdc As Long, ByVal crColor As Long) As Long
Public Declare Function SetTextColor Lib "gdi32" (ByVal hdc As Long, ByVal crColor As Long) As Long
Public Declare Function TextOut Lib "gdi32" Alias "TextOutA" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long, ByVal lpString As String, ByVal nCount As Long) As Long
Public Declare Function DrawFocusRect Lib "user32" (ByVal hdc As Long, lpRect As RECT) As Long
Public Declare Function GetSysColor Lib "user32" (ByVal nIndex As Long) As Long
Public Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long
Public Const COLOR_HIGHLIGHT = 13
Public Const COLOR_HIGHLIGHTTEXT = 14
Public Const COLOR_WINDOW = 5
Public Const COLOR_WINDOWTEXT = 8
Public Const LB_GETTEXT = &H189
Public Const LB_GETITEMHEIGHT = &H1A1
Public Const LB_GETITEMRECT = &H198
Public Const WM_DRAWITEM = &H2B
Public Const GWL_WNDPROC = (-4)
Public lPrevWndProc As Long
Public Function SubClassedList(ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Dim tItem As DRAWITEMSTRUCT
Dim sBuff As String * 255
Dim sItem As String
Dim lBack As Long
If Msg = WM_DRAWITEM Then
'Redraw the listbox
'This function only passes the Address of the DrawItem Structure, so we need to
'use the CopyMemory API to Get a Copy into the Variable we setup:
Call CopyMemory(tItem, ByVal lParam, Len(tItem))
'Make sure we're dealing with a Listbox
If tItem.CtlType = ODT_LISTBOX Then
'Get the Item Text
Call SendMessage(tItem.hwndItem , LB_GETTEXT, tItem.itemID, ByVal sBuff)
sItem = Left(sBuff, InStr(sBuff, Chr(0)) - 1)
If (tItem.itemState And ODS_FOCUS) Then
'Item has Focus, Highlight it, I'm using the Default Focus
'Colors for this example.
lBack = CreateSolidBrush(GetSysCol or(COLOR_H IGHLIGHT))
Call FillRect(tItem.hdc, tItem.rcItem, lBack)
Call SetBkColor(tItem.hdc, GetSysColor(COLOR_HIGHLIGH T))
Call SetTextColor(tItem.hdc, GetSysColor(COLOR_HIGHLIGH TTEXT))
TextOut tItem.hdc, tItem.rcItem.Left, tItem.rcItem.Top, ByVal sItem, Len(sItem)
DrawFocusRect tItem.hdc, tItem.rcItem
Else
'Item Doesn't Have Focus
'Create a Brush using the Color of the Listbox Window
lBack = CreateSolidBrush(tItem.ite mData)
'Paint the Item Area
Call FillRect(tItem.hdc, tItem.rcItem, lBack)
'Set the Text Colors, using the ForeColor specified in the ItemData of the Item
Call SetBkColor(tItem.hdc, tItem.itemData)
Call SetTextColor(tItem.hdc, GetSysColor(COLOR_WINDOWTE XT))
'Display the Item Text (this loses the check box to the left of the item)
TextOut tItem.hdc, tItem.rcItem.Left, tItem.rcItem.Top, ByVal sItem, Len(sItem)
End If
Call DeleteObject(lBack)
'Don't Need to Pass a Value on as we've just handled the Message ourselves
SubClassedList = 0
Exit Function
End If
End If
SubClassedList = CallWindowProc(lPrevWndPro c, hwnd, Msg, wParam, lParam)
End Function
Public Sub SubLists(ByVal hwnd As Long)
lPrevWndProc = SetWindowLong(hwnd, GWL_WNDPROC, AddressOf SubClassedList)
End Sub
Public Sub RemoveSubLists(ByVal hwnd As Long)
Call SetWindowLong(hwnd, GWL_WNDPROC, lPrevWndProc)
End Sub
The code is listed below
create a project with a listbox control. Set the listbox style to Checkbox
Option Explicit
Private Sub Form_Load()
Dim I As Integer
For I = 0 To 15
'Load a List of 0 to 15 with the Item Data
'Set to the QBColors 0 - 15
List1.AddItem "Color " & I
List1.itemData(List1.NewIn
Next
'Subclass the "Form", to Capture the Listbox Notification Messages
SubLists hwnd
End Sub
Private Sub Form_Unload(Cancel As Integer)
'Release the SubClassing, Very Import to Prevent Crashing!
RemoveSubLists hwnd
End Sub
Place the following code in a module:
Option Explicit
Public Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type
Public Type DRAWITEMSTRUCT
CtlType As Long
CtlID As Long
itemID As Long
itemAction As Long
itemState As Long
hwndItem As Long
hdc As Long
rcItem As RECT
itemData As Long
End Type
Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Public Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Public 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
Public Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Public Declare Function CreateSolidBrush Lib "gdi32" (ByVal crColor As Long) As Long
Public Declare Function FillRect Lib "user32" (ByVal hdc As Long, lpRect As RECT, ByVal hBrush As Long) As Long
Public Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long
Public Declare Function SetBkColor Lib "gdi32" (ByVal hdc As Long, ByVal crColor As Long) As Long
Public Declare Function SetTextColor Lib "gdi32" (ByVal hdc As Long, ByVal crColor As Long) As Long
Public Declare Function TextOut Lib "gdi32" Alias "TextOutA" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long, ByVal lpString As String, ByVal nCount As Long) As Long
Public Declare Function DrawFocusRect Lib "user32" (ByVal hdc As Long, lpRect As RECT) As Long
Public Declare Function GetSysColor Lib "user32" (ByVal nIndex As Long) As Long
Public Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long
Public Const COLOR_HIGHLIGHT = 13
Public Const COLOR_HIGHLIGHTTEXT = 14
Public Const COLOR_WINDOW = 5
Public Const COLOR_WINDOWTEXT = 8
Public Const LB_GETTEXT = &H189
Public Const LB_GETITEMHEIGHT = &H1A1
Public Const LB_GETITEMRECT = &H198
Public Const WM_DRAWITEM = &H2B
Public Const GWL_WNDPROC = (-4)
Public lPrevWndProc As Long
Public Function SubClassedList(ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Dim tItem As DRAWITEMSTRUCT
Dim sBuff As String * 255
Dim sItem As String
Dim lBack As Long
If Msg = WM_DRAWITEM Then
'Redraw the listbox
'This function only passes the Address of the DrawItem Structure, so we need to
'use the CopyMemory API to Get a Copy into the Variable we setup:
Call CopyMemory(tItem, ByVal lParam, Len(tItem))
'Make sure we're dealing with a Listbox
If tItem.CtlType = ODT_LISTBOX Then
'Get the Item Text
Call SendMessage(tItem.hwndItem
sItem = Left(sBuff, InStr(sBuff, Chr(0)) - 1)
If (tItem.itemState And ODS_FOCUS) Then
'Item has Focus, Highlight it, I'm using the Default Focus
'Colors for this example.
lBack = CreateSolidBrush(GetSysCol
Call FillRect(tItem.hdc, tItem.rcItem, lBack)
Call SetBkColor(tItem.hdc, GetSysColor(COLOR_HIGHLIGH
Call SetTextColor(tItem.hdc, GetSysColor(COLOR_HIGHLIGH
TextOut tItem.hdc, tItem.rcItem.Left, tItem.rcItem.Top, ByVal sItem, Len(sItem)
DrawFocusRect tItem.hdc, tItem.rcItem
Else
'Item Doesn't Have Focus
'Create a Brush using the Color of the Listbox Window
lBack = CreateSolidBrush(tItem.ite
'Paint the Item Area
Call FillRect(tItem.hdc, tItem.rcItem, lBack)
'Set the Text Colors, using the ForeColor specified in the ItemData of the Item
Call SetBkColor(tItem.hdc, tItem.itemData)
Call SetTextColor(tItem.hdc, GetSysColor(COLOR_WINDOWTE
'Display the Item Text (this loses the check box to the left of the item)
TextOut tItem.hdc, tItem.rcItem.Left, tItem.rcItem.Top, ByVal sItem, Len(sItem)
End If
Call DeleteObject(lBack)
'Don't Need to Pass a Value on as we've just handled the Message ourselves
SubClassedList = 0
Exit Function
End If
End If
SubClassedList = CallWindowProc(lPrevWndPro
End Function
Public Sub SubLists(ByVal hwnd As Long)
lPrevWndProc = SetWindowLong(hwnd, GWL_WNDPROC, AddressOf SubClassedList)
End Sub
Public Sub RemoveSubLists(ByVal hwnd As Long)
Call SetWindowLong(hwnd, GWL_WNDPROC, lPrevWndProc)
End Sub
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ASKER
This worked fine, We only needed to figure out how to draw the checkbox. We did have to find the code to retreive the status of the item selected.
Thank you,
Thank you,
Private Const ODS_SELECTED = &H1
bChecked = ((tItem.ItemState And ODS_SELECTED) = ODS_SELECTED)