Simple (hopefully) questions about treeview control.

[Elias Montoya]

 Hello,

I have 3 questions i have regarding firefly's functions for a treeview:

• Is there a firefly-based way to see what item was double-clicked? (my method currently works but traps the same message in the empty area of the control)
• Is there a firefly-based way to get the parent node of a treeview item?
• Is there a firefly-based way of getting a list of child nodes for a node?

I have very little knowledge about the treeview item, any pointers will be much appreciated.

[Paul Squires]

Here is code that I use to handle the treeviews in the FireFly Project Explorer (I removed some stuff but you should get the general idea). This should help with the doubleclick and rightclick:

Code Select Expand


'------------------------------------------------------------------------------------------------------------------------
Function FRMEXPLORER_CUSTOM ( _
                            hWndForm      As Dword, _  ' handle of Form
                            wMsg          As Long,  _  ' type of message
                            wParam        As Dword, _  ' first message parameter
                            lParam        As Long   _  ' second message parameter
                            ) As Long

   Local pForm  As FORM_TYPE Ptr
   Local ht     As TV_HITTESTINFO
   Local lpTV   As NM_TREEVIEW Ptr
   Local tItem  As TV_ITEM             
   Local wID    As Long
   Local hPopup As Long
     
   
   Select Case wMsg

      Case %WM_CONTEXTMENU ' Right click or Shift-F10 occured
        ' We got a right click
         ht.pt.x = LoWrd(lParam)
         ht.pt.y = HiWrd(lParam)
       
         If ScreenToClient( HWND_FRMEXPLORER_TREEVIEW1, ht.pt) Then
            SendMessage HWND_FRMEXPLORER_TREEVIEW1, %TVM_HITTEST, 0, VarPtr(ht)
            If ht.hItem Then
               TreeView_Select HWND_FRMEXPLORER_TREEVIEW1, ht.hItem, %TVGN_CARET
               hPopUp = ExplorerPopUpMenu( ht.hItem )
               TrackPopupMenu hPopUp, 0, LoWrd(lParam), HiWrd(lParam), 0, hwndForm, ByVal %Null
            End If   
         End If


     Case %WM_NOTIFY
        'determine which control is sending the notification
         Select Case LoWrd(wParam)
           Case IDC_FRMEXPLORER_TREEVIEW1, IDC_FRMEXPLORER_TREEVIEW2
             lpTV = lParam
             
             '// DOUBLE_CLICK //       
             If @lpTV.hdr.Code = %NM_DBLCLK Then   
             
                ' Display the code or form depending on which node is selected. That
                ' function is also used to respond to clicks on the Explorer Toolbar.
                DoViewFormOrCode -1
                Exit Function
                               
             End If
                 
             ' If the node is expanding/collapsing then check to see if it is the
             ' Forms or Modules nodes. If they are, then change the icons to show OPEN.
             If @lpTV.hdr.Code = %TVN_ITEMEXPANDED Then 
                 ' Set the Treeview's new selected icons
                 ' The itemNew structure contains the handle of the TreeView line
                 ' that is sending the notification message.
                 If (@lpTV.itemNew.hItem = g.hFormNode) Or (@lpTV.itemNew.hItem = g.hModuleNode) Or _
                    (@lpTV.itemNew.hItem = g.hResourceNode) Or (@lpTV.itemNew.hItem = g.hSpecialNode) Then
                     
                     tItem.hitem = @lpTV.itemNew.hItem
                     tItem.mask = %TVIF_IMAGE Or %TVIF_SELECTEDIMAGE
                     
                     If @lpTV.Action = %TVE_EXPAND Then
                        tItem.iImage = g.Explorer_OpenIcon
                        tItem.iSelectedImage = g.Explorer_OpenIcon
                     End If   
                     
                     If @lpTV.Action = %TVE_COLLAPSE Then
                        tItem.iImage = g.Explorer_ClosedIcon
                        tItem.iSelectedImage = g.Explorer_ClosedIcon
                     End If
                     
                     TreeView_SetItem HWND_FRMEXPLORER_TREEVIEW1, tItem   
                 
                 End If   
             End If
             
         End Select
       
   End Select
   
End Function


[Paul Squires]

Here is code to iterate all child nodes off of the specified node (I got this from Paul Noble a very long time ago) 

Code Select Expand


'//
'//  Calculates the number of immediate children under item <hUnder> in
'//  treeview <hTree>
'//
Function TVW_NodeCountUnder( ByVal hTree As Long, _
                             ByVal hUnder As Long _
                             ) As Long

   Local hItem  As Long
   Local mCount As Long

   'Locate the first child item...
   hItem = TreeView_GetNextItem( hTree, hUnder, %TVGN_CHILD )

   'Iterate over any items found...
   While hItem

      Incr mCount
      hItem = TreeView_GetNextItem( hTree, hItem, %TVGN_NEXT )

   Wend

   Function = mCount

End Function


[Paul Squires]

To get the Parent node (check out all of the functions in Jose's TreeViewCtrl.inc file):

Code Select Expand


' ========================================================================================
' Retrieves the parent item of the specified tree-view item.
' ========================================================================================
FUNCTION TreeView_GetParent (BYVAL hwndTV AS DWORD, BYVAL hItem AS DWORD) AS DWORD
   FUNCTION = TreeView_GetNextItem(hwndTV, hItem, %TVGN_PARENT)
END FUNCTION


[Elias Montoya]

 Thanks Paul!, extremely fast support you give!