Treeview color

[Joestes]

When I have a TreeViewGadget with option #PB_Tree_AlwaysShowSelection, is there a posibility to change the color of the bar when the gadget is out of focus?

What I mean: Can I change the pale greyish color when an item is selected but the gadget isn't active.

Thanks in advance!

[Shardik]

I have found some kind of hack to prevent turning the color from
blue to grey by "misusing" the attribute TVIS_DROPHILITED which
keeps an item's background blue even if loosing focus. I have used
this trick already 5 years ago to allow the multiselection of items in
a TreeGadget...

My code example even allows you to toggle between normal and
highlighted mode to see the difference:

Code: Select all

EnableExplicit

Procedure HighlightItem(NodeID.I, HighlightFlag.I)
  Protected ItemHandle.I
  Protected TVHitTest.TV_HITTESTINFO
  Protected TVItem.TV_ITEM

  ItemHandle = GadgetItemID(0, NodeID)

  If ItemHandle <> 0
    If TVHitTest\Flags <> #TVHT_ONITEMBUTTON
      TVItem\Mask = #TVIF_STATE
      TVItem\hItem = ItemHandle

      If HighlightFlag = #True
        TVItem\StateMask = #TVIS_DROPHILITED
        TVItem\State = #TVIS_DROPHILITED
      Else
        TVItem\StateMask = #TVIS_DROPHILITED
        TVItem\State = 0
      EndIf

      SendMessage_(GadgetID(0), #TVM_SETITEM, 0, @TVItem)

      RedrawWindow_(GadgetID(0), 0, 0, #RDW_UPDATENOW)
    EndIf
  EndIf
EndProcedure

Define i.I
Define NodeID.I
Define TreeGadgetIsInFocus.I

OpenWindow(0, 0, 0, 150, 220, "TreeGadget", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
TreeGadget(0, 10, 10, WindowWidth(0) - 20, WindowHeight(0) - 80, #PB_Tree_AlwaysShowSelection)
ButtonGadget(1, 10, WindowHeight(0) - 60, WindowWidth(0) - 20, 20, "Toggle focus")
CheckBoxGadget(2, 10, WindowHeight(0) - 30, WindowWidth(0) - 20, 20, "Keep blue on lost focus")

For i = 1 To 2
  AddGadgetItem (0, -1, "Node "+ Str(i), 0, 0)
  AddGadgetItem(0, -1, "Subnode 1", 0, 1)
  AddGadgetItem(0, -1, "Subnode 2", 0, 1)
  AddGadgetItem(0, -1, "Subnode 3", 0, 1)
Next i

; ----- Activate TreeGadget
SetActiveGadget(0)
; ----- Expand subnodes of first node
SetGadgetItemState(0, 0, #PB_Tree_Expanded)
; ----- Select 2nd subnode of 1st node
SetGadgetState(0, 2)

Repeat
  Select WaitWindowEvent()
    Case #PB_Event_CloseWindow
      Break
    Case #PB_Event_Gadget
      Select EventGadget()
        Case 0 ; <---- TreeGadget was clicked
          If GetGadgetState(2) = #True
            HighlightItem(NodeID, #False)
          EndIf          
        Case 1 ; <---- Button was pressed
          TreeGadgetIsInFocus ! 1
          
          If TreeGadgetIsInFocus
            If GetGadgetState(2)
              NodeID = GetGadgetState(0)
              HighlightItem(NodeID, #True)
            EndIf
            
            SetActiveGadget(1)
          Else
            SetActiveGadget(0)
          EndIf
        Case 2 ; <---- CheckBox was clicked
          If GetGadgetState(2)
            NodeID = GetGadgetState(0)
            HighlightItem(NodeID, #True)
          Else
            NodeID = GetGadgetState(0)
            SetGadgetState(0, NodeID)
            HighlightItem(NodeID, #False)
            SetActiveGadget(0)
          EndIf
      EndSelect
  EndSelect
ForEver