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Code: Select all

; ---------------------------------------------------------------------
; How to make TreeGadget Items Editable by the User
; by Timo Harter
; ---------------------------------------------------------------------
;
; By implementing this in your Program, the User can edit the Items
; of a TreeGadget by first right-clicking, and then left-clicking on it.
; (just like in Windows-Explorer)
;
; This is just a skeleton, how it is done, but it should be easy to
; understand, and implement in your own Programs.
; ---------------------------------------------------------------------


; This Constant will be needed:

#TVS_EDITLABELS = 8  ; The Window Style for Label Editing

; There's also a not defined Structure, we will need.

;     Structure NMTVDISPINFO
;       hdr.NMHDR
;       item.TV_ITEM
;     EndStructure

; We'll need one Global Variable for this, to store the Windows-Handle to the Gadget:

Global hWndTV

; We'll also need a Callback procedure for that. (If you never used one, don't be afraid,
; it's not that hard.). I'll just declare it here, the Procedure will be further down.

Declare Callback(Window, Message, wParam, lParam)

; First, we'll just create a Window, and a a TreeGadget.

OpenWindow(0, 0, 0, 200, 400, "TreeGadget Example", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
;     CreateGadgetList(WindowI())

; Store the Handle in the Global value:

hWndTV = TreeGadget(1, 5, 5, 190, 390)

; Now, here we run into our first Problem: There's no Flag for enabling Label Editing.
; so we'll have to to it ourselves.
; We can change that using the API Functions GetWindowLong_() and SetWindowLong_()
; What we do, is change a Style of the Window (That's the Stuff you specify with the Flags)

; First, get the existing Styles:

Styles = GetWindowLong_(hWndTV, #GWL_STYLE)

; Then Add Label Editing to these Styles:

Styles = Styles | #TVS_EDITLABELS

; Now Set the new Styles for the Gadget:

SetWindowLong_(hWndTV, #GWL_STYLE, Styles)

; Now Label Editing is allowed in this TreeGadget

; We'll now add some Items

AddGadgetItem(1, -1, "Item0",0,0)
AddGadgetItem(1, -1, "Item0",0,0)
;     OpenTreeGadgetNode()
AddGadgetItem(1, -1, "Item0",0,1)
AddGadgetItem(1, -1, "Item0",0,1)
;     CloseTreeGadgetNode()

; Now we'll need to set the Callback Procedure (for more Inofrmation see 'SetWindowCallback()'
; in the Help Files in the 'Window' Library.

SetWindowCallback(@Callback())

; That was all that was to be done in the Main prog, now your Main Loop can follow, that
; will handle all normal PureBasic Events.
; In this case, we handle no other Events, so this Loop only waits for the Close
; Button to be Pressed, and then Ends the Program.

While WaitWindowEvent() <> #PB_Event_CloseWindow: Wend
End

; This is the End of the Main Code.
; ------------------------------------------------------------------------------------

; Now following is the Callback Procedure. Here we handle the Editing.
; The Events are Send as Messages, where a Message is just a Constantt
; like the Event-Constants, wParam and lParam are just the parameters for
; these Events. You see, the Callback-thingy is not that hard.
; the only thing is to always use the skeleton you can find in the Help files
; (at 'SetWindowCallback()') as otherwise, your Program will crash.


Procedure Callback(Window, Message, wParam, lParam)
  result = #PB_ProcessPureBasicEvents
  
  ; The Messages we need are sent as a WM_NOTIFY Message. THis means, the Message will
  ; in our case always be #WM_NOTIFY, and the selection of the real Message will be made
  ; later.
  
  ; So we only need to find this Message:
  
  If Message = #WM_NOTIFY
    
    ; lParam contains the Pointer to a Structure with the actual Message:
    
    *lp.NMHDR = lParam
    
    ; now we see, what Message it was: (the code Member of the Structure contains the Message.)
    ; We'll need only 2 Messages:
    
    Select *lp\code
        
        ; fist is #TVN_BEGINLABELEDIT, this one is sent, if the user want's to edit an Item.
        
      Case #TVN_BEGINLABELEDIT
        
        ; here you can check, if you want to allow the user to edit this Item, or not.
        ; use GetGadgetState() to check, which Item in the TreeGadget is being edited.
        ; If you want to allow it, just do nothing, if not, you have to set
        ; 'result' to #TRUE.
        ; So if you want to always allow it, just write nothing here.
        
        ; In our case, we forbit editing Item 1: (which is actually the second in the Tree)
        ; but you can also do any other thing to find you, if you want to allo editing, this
        ; depends, on, what the Program will be for.
        
        If GetGadgetState(1) = 1
          result = #True
        EndIf
        
        ; ------------------------------------------
        
      Case #TVN_ENDLABELEDIT
        
        ; here you can check, if you want to accept the edited Text. For this, we'll
        ; need to get the new Text.
        
        ; lParam contains the Pointer to a Stucture with the Information
        ; As we allready know, lParam also pointed to the Structure from the
        ; #WM_NOTIFY Message. That's why this new Structure also contains the
        ; Structure NMHDR, which was from #WM_NOTIFY.
        
        *pvdi.NMTVDISPINFO = lParam
        
        ; The 'pszText' of the TV_ITEM Structure inside this Structure is a Pointer
        ; to the new entered Text. If this Pointer is #NULL, the Editing was
        ; chanceled by the User, and nothing will be changed. So we can ignore
        ; this Message in this case.
        ; Note: The Text can still be "", if the user deleted everything, but in this
        ; case, the Pointer will still not be #NULL.
        
        ; Check, that the 'pszText' Member is not #NULL
        
        If *pvdi\item\pszText <> #Null
          
          ; now, we get the entered Text:
          
          Text.s = PeekS(*pvdi\item\pszText)
          
          ; now you can decide, if you want to accept this Text, or not. If you want
          ; to find out the Item Number, use GetGadgetState().
          
          ; If you want to accept the Text, set 'result' to #True, if not, set it to
          ; #False.
          
          ; In our case, we don't want the user to enter an empty String.
          
          If Text = ""
            result = #False
          Else
            result = #True
          EndIf
          
        EndIf
        
        ; ------------------------------------------
        
        ; Well, that was all, you need, to make a TreeGadget editable, no a very big deal :wink:
        ; We now just close all started Contitions
        
        ; the selection of the Message   
        
    EndSelect
    
    ; The If contition for #WM_NOTIFY
    
  EndIf
  
  ; now, we return the 'return' value:
  
  ProcedureReturn result
  
  ; that's it, for the callback procedure.
  
EndProcedure

; ---------------------------------------------------------------------

Code: Select all

; here comes the ListIconGadget code...
; -------------------------------------------------------------------

#List = 1 ; just to make the Code more readable.

; This Structure is a little different that the one for TreeGadget
; (it is LV_ITEM instead of TV_ITEM, and the Name is different :)  )

Structure NMLVDISPINFO
  hdr.NMHDR
  item.LV_ITEM
EndStructure

Declare Callback(Window.l, Message.l, wParam.l, lParam.l)

OpenWindow(0, 0, 0, 200, 400, #PB_Window_SystemMenu | #PB_Window_Screencentered, "ListIconGadget Example")
CreateGadgetList(WindowID())

ListIconGadget(#List, 5, 5, 190, 390, "Edit Items:", 150)

; change the Styles: here, we add #LVS_EDITLABELS

Styles.l = GetWindowLong_(GadgetID(#List), #GWL_STYLE)
Styles = Styles | #LVS_EDITLABELS
SetWindowLong_(GadgetID(#List), #GWL_STYLE, Styles)

AddGadgetItem(1, 0, "Item0")
AddGadgetItem(1, 0, "Item0")
AddGadgetItem(1, 0, "Item0")
AddGadgetItem(1, 0, "Item0")

SetWindowCallback(@Callback())


While WaitWindowEvent()  #PB_EventCloseWindow: Wend
End

; ------------------------------------------------------------------------------------

Procedure Callback(Window.l, Message.l, wParam.l, lParam.l)
  result = #PB_ProcessPureBasicEvents 
    
  If Message = #WM_NOTIFY
      
      *lp.NMHDR = lParam
      
      ; check, if it was really this Gadget, who sent the Message:
      ; this can also be done for TreeGadgets (i forgot that)
      
      If *lp\hwndFrom = GadgetID(#List)
      
        ; get real Message:
        
        Select *lp\code
        
          Case #LVN_BEGINLABELEDIT
                     
             ; this is just the same as for TreeGadget, only the Message Constant is different.
             ; return #True, to forbit editing, #False to allow it.
           
             If GetGadgetState(1) = 1
               result = #True
             EndIf
           
             ; ------------------------------------------
           
         Case #LVN_ENDLABELEDIT
       
             ; This is also the same, just the Structure Name and the Constant has changed.
           
             *pvdi.NMLVDISPINFO = lParam
           
             ; Even the Members of the Structure are the same:         
           
             If *pvdi\item\pszText  #NULL
             
               Text.s = PeekS(*pvdi\item\pszText)
             
             ; If you want to accept the Text, set 'result' to #True, if not, set it to
             ; #False.
             
             
               If Text = ""
                 result = #False
               Else
                 result = #True
               EndIf
            
             EndIf
           
           ; ------------------------------------------
          
       
        EndSelect
      
      EndIf
  
  EndIf
  
  ProcedureReturn result
  
EndProcedure

Code: Select all

; ---------------------------------------------------------------------; How to make TreeGadget Items Editable by the User; by Timo Harter; ---------------------------------------------------------------------;; By implementing this in your Program, the User can edit the Items; of a TreeGadget by first right-clicking, and then left-clicking on it.; (just like in Windows-Explorer) ;; This is just a skeleton, how it is done, but it should be easy to ; understand, and implement in your own Programs.; ---------------------------------------------------------------------; This Constant will be needed:#TVS_EDITLABELS = 8  ; The Window Style for Label Editing; There's also a not defined Structure, we will need.Structure NMTVDISPINFO  hdr.NMHDR  item.TV_ITEMEndStructure; We'll need one Global Variable for this, to store the Windows-Handle to the Gadget:Global hWndTV.l; We'll also need a Callback procedure for that. (If you never used one, don't be afraid, ; it's not that hard.). I'll just declare it here, the Procedure will be further down.Declare Callback(Window.l, Message.l, wParam.l, lParam.l); First, we'll just create a Window, and a a TreeGadget.OpenWindow(0, 0, 0, 200, 400, #PB_Window_SystemMenu | #PB_Window_Screencentered, "TreeGadget Example")CreateGadgetList(WindowID()); Store the Handle in the Global value:hWndTV = TreeGadget(1, 5, 5, 190, 390); Now, here we run into our first Problem: There's no Flag for enabling Label Editing.; so we'll have to to it ourselves.; We can change that using the API Functions GetWindowLong_() and SetWindowLong_(); What we do, is change a Style of the Window (That's the Stuff you specify with the Flags); First, get the existing Styles:Styles.l = GetWindowLong_(hWndTV, #GWL_STYLE); Then Add Label Editing to these Styles:Styles = Styles | #TVS_EDITLABELS; Now Set the new Styles for the Gadget:SetWindowLong_(hWndTV, #GWL_STYLE, Styles); Now Label Editing is allowed in this TreeGadget; We'll now add some ItemsAddGadgetItem(1, 0, "Item0")AddGadgetItem(1, 0, "Item0")OpenTreeGadgetNode()  AddGadgetItem(1, 0, "Item0")  AddGadgetItem(1, 0, "Item0")CloseTreeGadgetNode(); Now we'll need to set the Callback Procedure (for more Inofrmation see 'SetWindowCallback()'; in the Help Files in the 'Window' Library.SetWindowCallback(@Callback()); That was all that was to be done in the Main prog, now your Main Loop can follow, that; will handle all normal PureBasic Events.; In this case, we handle no other Events, so this Loop only waits for the Close; Button to be Pressed, and then Ends the Program.While WaitWindowEvent() <> #PB_EventCloseWindow: WendEnd; This is the End of the Main Code.; ------------------------------------------------------------------------------------; Now following is the Callback Procedure. Here we handle the Editing.; The Events are Send as Messages, where a Message is just a Constantt; like the Event-Constants, wParam and lParam are just the parameters for; these Events. You see, the Callback-thingy is not that hard.; the only thing is to always use the skeleton you can find in the Help files; (at 'SetWindowCallback()') as otherwise, your Program will crash.Procedure Callback(Window.l, Message.l, wParam.l, lParam.l)  result = #PB_ProcessPureBasicEvents     ; The Messages we need are sent as a WM_NOTIFY Message. THis means, the Message will  ; in our case always be #WM_NOTIFY, and the selection of the real Message will be made  ; later.    ; So we only need to find this Message:    If Message = #WM_NOTIFY             ; lParam contains the Pointer to a Structure with the actual Message:             *lp.NMHDR = lParam            ; now we see, what Message it was: (the code Member of the Structure contains the Message.)      ; We'll need only 2 Messages:            Select *lp\code              ; fist is #TVN_BEGINLABELEDIT, this one is sent, if the user want's to edit an Item.                Case #TVN_BEGINLABELEDIT                      ; here you can check, if you want to allow the user to edit this Item, or not.           ; use GetGadgetState() to check, which Item in the TreeGadget is being edited.           ; If you want to allow it, just do nothing, if not, you have to set           ; 'result' to #TRUE.           ; So if you want to always allow it, just write nothing here.                      ; In our case, we forbit editing Item 1: (which is actually the second in the Tree)           ; but you can also do any other thing to find you, if you want to allo editing, this           ; depends, on, what the Program will be for.                      If GetGadgetState(1) = 1             result = #True           EndIf                      ; ------------------------------------------                  Case #TVN_ENDLABELEDIT                  ; here you can check, if you want to accept the edited Text. For this, we'll           ; need to get the new Text.                      ; lParam contains the Pointer to a Stucture with the Information           ; As we allready know, lParam also pointed to the Structure from the           ; #WM_NOTIFY Message. That's why this new Structure also contains the           ; Structure NMHDR, which was from #WM_NOTIFY.                      *pvdi.NMTVDISPINFO = lParam                      ; The 'pszText' of the TV_ITEM Structure inside this Structure is a Pointer           ; to the new entered Text. If this Pointer is #NULL, the Editing was           ; chanceled by the User, and nothing will be changed. So we can ignore           ; this Message in this case.           ; Note: The Text can still be "", if the user deleted everything, but in this           ; case, the Pointer will still not be #NULL.                      ; Check, that the 'pszText' Member is not #NULL                      If *pvdi\item\pszText <> #NULL                        ; now, we get the entered Text:                          Text.s = PeekS(*pvdi\item\pszText)                          ; now you can decide, if you want to accept this Text, or not. If you want             ; to find out the Item Number, use GetGadgetState().                          ; If you want to accept the Text, set 'result' to #True, if not, set it to             ; #False.                          ; In our case, we don't want the user to enter an empty String.                          If Text = ""               result = #False             Else               result = #True             EndIf                     EndIf                      ; ------------------------------------------                     ; Well, that was all, you need, to make a TreeGadget editable, no a very big deal            ; We now just close all started Contitions            ; the selection of the Message                 EndSelect        ; The If contition for #WM_NOTIFY    EndIf    ; now, we return the 'return' value:    ProcedureReturn result; that's it, for the callback procedure.  EndProcedure; ---------------------------------------------------------------------

Code: Select all

; ---------------------------------------------------------------------
; How to make TreeGadget Items Editable by the User
; by Timo Harter
; ---------------------------------------------------------------------
;
; By implementing this in your Program, the User can edit the Items
; of a TreeGadget by first right-clicking, and then left-clicking on it.
; (just like in Windows-Explorer) 
;
; This is just a skeleton, how it is done, but it should be easy to 
; understand, and implement in your own Programs.
; ---------------------------------------------------------------------


; This Constant will be needed:

#TVS_EDITLABELS = 8  ; The Window Style for Label Editing

; There's also a not defined Structure, we will need.

Structure NMTVDISPINFO
  hdr.NMHDR
  item.TV_ITEM
EndStructure

; We'll need one Global Variable for this, to store the Windows-Handle to the Gadget:

Global hWndTV.l

; We'll also need a Callback procedure for that. (If you never used one, don't be afraid, 
; it's not that hard.). I'll just declare it here, the Procedure will be further down.

Declare Callback(Window.l, Message.l, wParam.l, lParam.l)

; First, we'll just create a Window, and a a TreeGadget.

OpenWindow(0, 0, 0, 200, 400, #PB_Window_SystemMenu | #PB_Window_Screencentered, "TreeGadget Example")
CreateGadgetList(WindowID())

; Store the Handle in the Global value:

hWndTV = TreeGadget(1, 5, 5, 190, 390)

; Now, here we run into our first Problem: There's no Flag for enabling Label Editing.
; so we'll have to to it ourselves.
; We can change that using the API Functions GetWindowLong_() and SetWindowLong_()
; What we do, is change a Style of the Window (That's the Stuff you specify with the Flags)

; First, get the existing Styles:

Styles.l = GetWindowLong_(hWndTV, #GWL_STYLE)

; Then Add Label Editing to these Styles:

Styles = Styles | #TVS_EDITLABELS

; Now Set the new Styles for the Gadget:

SetWindowLong_(hWndTV, #GWL_STYLE, Styles)

; Now Label Editing is allowed in this TreeGadget

; We'll now add some Items

AddGadgetItem(1, 0, "Item0")
AddGadgetItem(1, 0, "Item0")
OpenTreeGadgetNode()
  AddGadgetItem(1, 0, "Item0")
  AddGadgetItem(1, 0, "Item0")
CloseTreeGadgetNode()

; Now we'll need to set the Callback Procedure (for more Inofrmation see 'SetWindowCallback()'
; in the Help Files in the 'Window' Library.

SetWindowCallback(@Callback())

; That was all that was to be done in the Main prog, now your Main Loop can follow, that
; will handle all normal PureBasic Events.
; In this case, we handle no other Events, so this Loop only waits for the Close
; Button to be Pressed, and then Ends the Program.

While WaitWindowEvent() <> #PB_EventCloseWindow: Wend
End

; This is the End of the Main Code.
; ------------------------------------------------------------------------------------

; Now following is the Callback Procedure. Here we handle the Editing.
; The Events are Send as Messages, where a Message is just a Constantt
; like the Event-Constants, wParam and lParam are just the parameters for
; these Events. You see, the Callback-thingy is not that hard.
; the only thing is to always use the skeleton you can find in the Help files
; (at 'SetWindowCallback()') as otherwise, your Program will crash.


Procedure Callback(Window.l, Message.l, wParam.l, lParam.l)
  result = #PB_ProcessPureBasicEvents 
  
  ; The Messages we need are sent as a WM_NOTIFY Message. THis means, the Message will
  ; in our case always be #WM_NOTIFY, and the selection of the real Message will be made
  ; later.
  
  ; So we only need to find this Message:
  
  If Message = #WM_NOTIFY 
      
      ; lParam contains the Pointer to a Structure with the actual Message: 
      
      *lp.NMHDR = lParam
      
      ; now we see, what Message it was: (the code Member of the Structure contains the Message.)
      ; We'll need only 2 Messages:
      
      Select *lp\code
      
        ; fist is #TVN_BEGINLABELEDIT, this one is sent, if the user want's to edit an Item.
        
        Case #TVN_BEGINLABELEDIT
           
           ; here you can check, if you want to allow the user to edit this Item, or not.
           ; use GetGadgetState() to check, which Item in the TreeGadget is being edited.
           ; If you want to allow it, just do nothing, if not, you have to set
           ; 'result' to #TRUE.
           ; So if you want to always allow it, just write nothing here.
           
           ; In our case, we forbit editing Item 1: (which is actually the second in the Tree)
           ; but you can also do any other thing to find you, if you want to allo editing, this
           ; depends, on, what the Program will be for.
           
           If GetGadgetState(1) = 1
             result = #True
           EndIf
           
           ; ------------------------------------------
           
       Case #TVN_ENDLABELEDIT
       
           ; here you can check, if you want to accept the edited Text. For this, we'll
           ; need to get the new Text.
           
           ; lParam contains the Pointer to a Stucture with the Information
           ; As we allready know, lParam also pointed to the Structure from the
           ; #WM_NOTIFY Message. That's why this new Structure also contains the
           ; Structure NMHDR, which was from #WM_NOTIFY.
           
           *pvdi.NMTVDISPINFO = lParam
           
           ; The 'pszText' of the TV_ITEM Structure inside this Structure is a Pointer
           ; to the new entered Text. If this Pointer is #NULL, the Editing was
           ; chanceled by the User, and nothing will be changed. So we can ignore
           ; this Message in this case.
           ; Note: The Text can still be "", if the user deleted everything, but in this
           ; case, the Pointer will still not be #NULL.
           
           ; Check, that the 'pszText' Member is not #NULL
           
           If *pvdi\item\pszText <> #NULL
           
             ; now, we get the entered Text:
             
             Text.s = PeekS(*pvdi\item\pszText)
             
             ; now you can decide, if you want to accept this Text, or not. If you want
             ; to find out the Item Number, use GetGadgetState().
             
             ; If you want to accept the Text, set 'result' to #True, if not, set it to
             ; #False.
             
             ; In our case, we don't want the user to enter an empty String.
             
             If Text = ""
               result = #False
             Else
               result = #True
             EndIf
          
           EndIf
           
           ; ------------------------------------------
          
           ; Well, that was all, you need, to make a TreeGadget editable, no a very big deal Wink
           ; We now just close all started Contitions
      
      ; the selection of the Message    
       
      EndSelect
      
  ; The If contition for #WM_NOTIFY
  
  EndIf
  
  ; now, we return the 'return' value:
  
  ProcedureReturn result

; that's it, for the callback procedure.
  
EndProcedure

; ---------------------------------------------------------------------

Code: Select all

; This Constant will be needed: 

#TVS_EDITLABELS = 8  ; The Window Style for Label Editing 

; There's also a not defined Structure, we will need. 

; Already declared
; Structure NMTVDISPINFO 
  ; hdr.NMHDR 
  ; item.TV_ITEM 
; EndStructure 

; We'll need one Global Variable for this, to store the Windows-Handle to the Gadget: 

Global hWndTV.l 

; We'll also need a Callback procedure for that. (If you never used one, don't be afraid, 
; it's not that hard.). I'll just declare it here, the Procedure will be further down. 

Declare Callback(Window.l, message.l, wParam.l, lParam.l) 

; First, we'll just create a Window, and a a TreeGadget. 

OpenWindow(0, 0, 0, 200, 400, #PB_Window_SystemMenu | #PB_Window_Screencentered, "TreeGadget Example") 
CreateGadgetList(WindowID()) 

; Store the Handle in the Global value: 

hWndTV = TreeGadget(1, 5, 5, 190, 390) 

; Now, here we run into our first Problem: There's no Flag for enabling Label Editing. 
; so we'll have to to it ourselves. 
; We can change that using the API Functions GetWindowLong_() and SetWindowLong_() 
; What we do, is change a Style of the Window (That's the Stuff you specify with the Flags) 

; First, get the existing Styles: 

Styles.l = GetWindowLong_(hWndTV, #GWL_STYLE) 

; Then Add Label Editing to these Styles: 

Styles = Styles | #TVS_EDITLABELS 

; Now Set the new Styles for the Gadget: 

SetWindowLong_(hWndTV, #GWL_STYLE, Styles) 

; Now Label Editing is allowed in this TreeGadget 

; We'll now add some Items 

AddGadgetItem(1, -1, "Item0") 
AddGadgetItem(1, -1, "Item1") 
OpenTreeGadgetNode(1) 
AddGadgetItem(1, -1, "Item2") 
AddGadgetItem(1, -1, "Item3") 
CloseTreeGadgetNode(1) 

; Now we'll need to set the Callback Procedure (for more Inofrmation see 'SetWindowCallback()' 
; in the Help Files in the 'Window' Library. 

SetWindowCallback(@Callback()) 

; That was all that was to be done in the Main prog, now your Main Loop can follow, that 
; will handle all normal PureBasic Events. 
; In this case, we handle no other Events, so this Loop only waits for the Close 
; Button to be Pressed, and then Ends the Program. 

While WaitWindowEvent() <> #PB_EventCloseWindow: Wend 
End 

; This is the End of the Main Code. 
; ------------------------------------------------------------------------------------ 

; Now following is the Callback Procedure. Here we handle the Editing. 
; The Events are Send as Messages, where a Message is just a Constantt 
; like the Event-Constants, wParam and lParam are just the parameters for 
; these Events. You see, the Callback-thingy is not that hard. 
; the only thing is to always use the skeleton you can find in the Help files 
; (at 'SetWindowCallback()') as otherwise, your Program will crash. 


Procedure Callback(Window.l, message.l, wParam.l, lParam.l) 
  result = #PB_ProcessPureBasicEvents 
  
  ; The Messages we need are sent as a WM_NOTIFY Message. THis means, the Message will 
  ; in our case always be #WM_NOTIFY, and the selection of the real Message will be made 
  ; later. 
  
  ; So we only need to find this Message: 
  
  If message = #WM_NOTIFY 
    
    ; lParam contains the Pointer to a Structure with the actual Message: 
    
    *lp.NMHDR = lParam 
    
    ; now we see, what Message it was: (the code Member of the Structure contains the Message.) 
    ; We'll need only 2 Messages: 
    
    Select *lp\code 
      
      ; fist is #TVN_BEGINLABELEDIT, this one is sent, if the user want's to edit an Item. 
      
      Case #TVN_BEGINLABELEDIT 
        
        ; here you can check, if you want to allow the user to edit this Item, or not. 
        ; use GetGadgetState() to check, which Item in the TreeGadget is being edited. 
        ; If you want to allow it, just do nothing, if not, you have to set 
        ; 'result' to #TRUE. 
        ; So if you want to always allow it, just write nothing here. 
        
        ; In our case, we forbit editing Item 1: (which is actually the second in the Tree) 
        ; but you can also do any other thing to find you, if you want to allo editing, this 
        ; depends, on, what the Program will be for. 
        
        If GetGadgetState(1) = 1 
          result = #TRUE 
        EndIf 
        
        ; ------------------------------------------ 
        
      Case #TVN_ENDLABELEDIT 
        
        ; here you can check, if you want to accept the edited Text. For this, we'll 
        ; need to get the new Text. 
        
        ; lParam contains the Pointer to a Stucture with the Information 
        ; As we allready know, lParam also pointed to the Structure from the 
        ; #WM_NOTIFY Message. That's why this new Structure also contains the 
        ; Structure NMHDR, which was from #WM_NOTIFY. 
        
        *pvdi.NMTVDISPINFO = lParam 
        
        ; The 'pszText' of the TV_ITEM Structure inside this Structure is a Pointer 
        ; to the new entered Text. If this Pointer is #NULL, the Editing was 
        ; chanceled by the User, and nothing will be changed. So we can ignore 
        ; this Message in this case. 
        ; Note: The Text can still be "", if the user deleted everything, but in this 
        ; case, the Pointer will still not be #NULL. 
        
        ; Check, that the 'pszText' Member is not #NULL 
        
        If *pvdi\item\pszText <> #NULL 
          
          ; now, we get the entered Text: 
          
          Text.s = PeekS(*pvdi\item\pszText) 
          
          ; now you can decide, if you want to accept this Text, or not. If you want 
          ; to find out the Item Number, use GetGadgetState(). 
          
          ; If you want to accept the Text, set 'result' to #True, if not, set it to 
          ; #False. 
          
          ; In our case, we don't want the user to enter an empty String. 
          
          If Text = "" 
            result = #FALSE 
          Else 
            result = #TRUE 
          EndIf 
          
        EndIf 
        
        ; ------------------------------------------ 
        
        ; Well, that was all, you need, to make a TreeGadget editable, no a very big deal Wink 
        ; We now just close all started Contitions 
        
        ; the selection of the Message    
        
    EndSelect 
    
    ; The If contition for #WM_NOTIFY 
    
  EndIf 
  
  ; now, we return the 'return' value: 
  
  ProcedureReturn result 
  
  ; that's it, for the callback procedure. 
  
EndProcedure