Improve ListFilterEdit, make it more object oriented

git-svn-id: trunk@31539 -

components/lazcontrols/listfilteredit.pas

@@ -16,6 +16,56 @@ type
   TImageIndexEvent = function (Str: String; Data: TObject;
                                var IsEnabled: Boolean): Integer of object;
 
+  TListFilterEdit = class;
+
+  { TViewControl }
+
+  // A wrapper for the visual control displaying data
+  TViewControl = class
+  private
+    fOwner: TListFilterEdit;
+    fImgIndex: Integer;
+    fSortedData: TStringList;
+    function CompareFNs(AFilename1,AFilename2: string): integer;
+    procedure SortAndFilter;
+    procedure ApplyFilter; virtual; abstract;
+    procedure StoreSelection; virtual; abstract;
+    procedure RestoreSelection; virtual; abstract;
+  public
+    constructor Create(AOwner: TListFilterEdit);
+    destructor Destroy; override;
+  end;
+
+  { TViewControlTreeview }
+
+  TViewControlTreeview = class(TViewControl)
+  private
+    fTreeview: TTreeview;
+    fTVNodeStack: TFPList;
+    procedure ApplyFilter; override;
+    procedure StoreSelection; override;
+    procedure RestoreSelection; override;
+    procedure FreeTVNodeData(Node: TTreeNode);
+    procedure TVDeleteUnneededNodes(p: integer);
+    procedure TVClearUnneededAndCreateHierachy(Filename: string);
+  public
+    constructor Create(AOwner: TListFilterEdit; aTreeview: TTreeview);
+    destructor Destroy; override;
+  end;
+
+  { TViewControlListbox }
+
+  TViewControlListbox = class(TViewControl)
+  private
+    fListbox: TListbox;
+    procedure ApplyFilter; override;
+    procedure StoreSelection; override;
+    procedure RestoreSelection; override;
+  public
+    constructor Create(AOwner: TListFilterEdit; aListbox: TListbox);
+    destructor Destroy; override;
+  end;
+
   { TListFilterEdit }
 
   TListFilterEdit = class(TCustomEditButton)
@@ -30,10 +80,12 @@ type
     // A control showing the (filtered) data. These are exclusive, only one is used.
     fFilteredTreeview: TTreeview;
     fFilteredListbox: TListbox;
-    fImageIndexDirectory: integer;  // Needed if directory structure is shown.
+    fViewControlWrapper: TViewControl; // Wraps either TTreeview or TListbox.
+    fImageIndexDirectory: integer;     // Needed if directory structure is shown.
     fImages4Listbox: TCustomImageList; // Listbox does not have ImageList of its own.
-    fNeedUpdate: boolean;
+    fNeedUpdate: Boolean;
-    fIdleConnected: boolean;
+    fIdleConnected: Boolean;
+    fIsFirstUpdate: Boolean;
     fSelectedPart: TObject;         // Select this node on next update
     fSelectionList: TStringList;    // or store/restore the old selections here.
     fShowDirHierarchy: Boolean;     // Show direcories / files as a tree structure.
@@ -41,30 +93,17 @@ type
     // Full filename in node data is needed when showing the directory hierarchy.
     // It is stored automatically if the map is populated by MapShortToFullFilename.
     fFilenameMap: TStringToStringTree;
-    fTVNodeStack: TFPList;
     // Data supplied by caller through Data property.
     // Objects property is passed to OnGetImageIndex.
     fOriginalData: TStringList;
     // Data sorted for viewing.
-    fSortedData: TStringList;
     fRootNode: TTreeNode;           // The filtered items are under this node.
     fOnGetImageIndex: TImageIndexEvent;
     procedure SetFilter(const AValue: string);
     procedure SetFilteredTreeview(const AValue: TTreeview);
     procedure SetFilteredListbox(const AValue: TListBox);
     procedure SetShowDirHierarchy(const AValue: Boolean);
-    procedure StoreTreeSelection;
+    procedure SetIdleConnected(const AValue: Boolean);
-    procedure StoreListSelection;
-    procedure RestoreTreeSelection;
-    procedure RestoreListSelection;
-    procedure FreeTVNodeData(Node: TTreeNode);
-    procedure TVDeleteUnneededNodes(p: integer);
-    procedure TVClearUnneededAndCreateHierachy(Filename: string);
-    function CompareFNs(AFilename1,AFilename2: string): integer;
-    procedure SortAndFilter;
-    procedure ApplyFilterToListBox;
-    procedure ApplyFilterToTreeview;
-    procedure SetIdleConnected(const AValue: boolean);
   protected
     function GetDefaultGlyph: TBitmap; override;
     function GetDefaultGlyphName: String; override;
@@ -78,8 +117,9 @@ type
   public
     property Filter: string read fFilter write SetFilter;
     property ImageIndexDirectory: integer read fImageIndexDirectory write fImageIndexDirectory;
-    property IdleConnected: boolean read fIdleConnected write SetIdleConnected;
+    property IdleConnected: Boolean read fIdleConnected write SetIdleConnected;
     property SelectedPart: TObject read fSelectedPart write fSelectedPart;
+    property SelectionList: TStringList read fSelectionList;
     property ShowDirHierarchy: Boolean read fShowDirHierarchy write SetShowDirHierarchy;
     property SortData: Boolean read fSortData write fSortData;
     property Data: TStringList read fOriginalData;
@@ -163,11 +203,297 @@ begin
   RegisterComponents('LazControls',[TListFilterEdit]);
 end;
 
+{ TFileNameItem }
+
 constructor TFileNameItem.Create(AFilename: string);
 begin
   Filename:=AFilename;
 end;
 
+{ TViewControl }
+
+constructor TViewControl.Create(AOwner: TListFilterEdit);
+begin
+  inherited Create;
+  fOwner:=AOwner;
+  fImgIndex:=-1;
+  fSortedData:=TStringList.Create;
+end;
+
+destructor TViewControl.Destroy;
+begin
+  fSortedData.Free;
+  inherited Destroy;
+end;
+
+function TViewControl.CompareFNs(AFilename1,AFilename2: string): integer;
+begin
+  if fOwner.fSortData then
+    Result:=CompareFilenames(AFilename1, AFilename2)
+  else if fOwner.fShowDirHierarchy then
+    Result:=CompareFilenames(ExtractFilePath(AFilename1), ExtractFilePath(AFilename2))
+  else
+    Result:=0;
+end;
+
+procedure TViewControl.SortAndFilter;
+// Copy data from fOriginalData to fSortedData in sorted order
+var
+  Origi, i: Integer;
+  FileN: string;
+begin
+  fSortedData.Clear;
+  for Origi:=0 to fOwner.fOriginalData.Count-1 do begin
+    FileN:=fOwner.fOriginalData[Origi];
+    if (fOwner.Filter='') or (Pos(fOwner.Filter,lowercase(FileN))>0) then begin
+      i:=fSortedData.Count-1;
+      while i>=0 do begin
+        if CompareFNs(FileN,fSortedData[i])>=0 then break;
+        dec(i);
+      end;
+      fSortedData.InsertObject(i+1,FileN, fOwner.fOriginalData.Objects[Origi]);
+    end;
+  end;
+end;
+
+{ TViewControlTreeview }
+
+constructor TViewControlTreeview.Create(AOwner: TListFilterEdit; aTreeview: TTreeview);
+begin
+  inherited Create(AOwner);
+  fTreeview:=aTreeview;
+end;
+
+destructor TViewControlTreeview.Destroy;
+begin
+  FreeTVNodeData(fOwner.fRootNode);
+  inherited Destroy;
+end;
+
+procedure TViewControlTreeview.ApplyFilter;
+var
+  TVNode: TTreeNode;
+  i: Integer;
+  FileN, s: string;
+  ena: Boolean;
+begin
+  with fOwner do begin
+    if fFilenameMap.Count > 0 then
+      FreeTVNodeData(fRootNode);   // Free node data now, it will be filled later.
+    if Assigned(fRootNode) then    // Delete old tree nodes.
+      fRootNode.DeleteChildren
+    else
+      fTreeview.Items.Clear;
+    if fShowDirHierarchy then
+      fTVNodeStack:=TFPList.Create;
+    fTreeview.BeginUpdate;
+    for i:=0 to fSortedData.Count-1 do begin
+      FileN:=fSortedData[i];
+      if fShowDirHierarchy then begin
+        TVClearUnneededAndCreateHierachy(FileN);
+        TVNode:=TTreeNode(fTVNodeStack[fTVNodeStack.Count-1]);
+      end
+      else if Assigned(fRootNode) then
+        TVNode:=fTreeview.Items.AddChild(fRootNode,FileN)
+      else
+        TVNode:=fTreeview.Items.Add(Nil,FileN);
+      if fFilenameMap.Count > 0 then begin
+        s:=FileN;
+        if fFilenameMap.Contains(FileN) then
+          s:=fFilenameMap[FileN];           // Full file name.
+        TVNode.Data:=TFileNameItem.Create(s);
+      end;
+      if Assigned(OnGetImageIndex) then
+        fImgIndex:=OnGetImageIndex(FileN, fSortedData.Objects[i], ena);
+      TVNode.ImageIndex:=fImgIndex;
+      TVNode.SelectedIndex:=fImgIndex;
+      if Assigned(fSelectedPart) then
+        TVNode.Selected:=fSelectedPart=fSortedData.Objects[i];
+    end;
+    if fShowDirHierarchy then      // TVDeleteUnneededNodes(0); ?
+      fTVNodeStack.Free;
+    if Assigned(fRootNode) then
+      fRootNode.Expanded:=True;
+    fTreeview.EndUpdate;
+  end;
+end;
+
+procedure TViewControlTreeview.StoreSelection;
+var
+  ANode: TTreeNode;
+begin
+  ANode:=fTreeview.Selected;
+  while ANode<>nil do begin
+    fOwner.fSelectionList.Insert(0,ANode.Text);
+    ANode:=ANode.Parent;
+  end;
+end;
+
+procedure TViewControlTreeview.RestoreSelection;
+var
+  ANode: TTreeNode;
+  CurText: string;
+begin
+  ANode:=nil;
+  with fOwner do begin
+    while fSelectionList.Count>0 do begin
+      CurText:=fSelectionList[0];
+      if ANode=nil then
+        ANode:=fTreeview.Items.GetFirstNode
+      else
+        ANode:=ANode.GetFirstChild;
+      while (ANode<>nil) and (ANode.Text<>CurText) do
+        ANode:=ANode.GetNextSibling;
+      if ANode=nil then break;
+      fSelectionList.Delete(0);
+    end;
+    if ANode<>nil then
+      fTreeview.Selected:=ANode;
+    fSelectionList.Clear;
+  end;
+end;
+
+procedure TViewControlTreeview.FreeTVNodeData(Node: TTreeNode);
+var
+  Child: TTreeNode;
+begin
+  if Node=nil then exit;
+  if (Node.Data<>nil) then begin
+    TObject(Node.Data).Free;
+    Node.Data:=nil;
+  end;
+  Child:=Node.GetFirstChild;
+  while Child<>nil do
+  begin
+    FreeTVNodeData(Child);
+    Child:=Child.GetNextSibling;
+  end;
+end;
+
+procedure TViewControlTreeview.TVDeleteUnneededNodes(p: integer);
+// delete all nodes behind the nodes in the stack, and depth>=p
+var
+  i: Integer;
+  Node: TTreeNode;
+begin
+  for i:=fTVNodeStack.Count-1 downto p do begin
+    Node:=TTreeNode(fTVNodeStack[i]);
+    while Node.GetNextSibling<>nil do
+      Node.GetNextSibling.Free;
+  end;
+  fTVNodeStack.Count:=p;
+end;
+
+procedure TViewControlTreeview.TVClearUnneededAndCreateHierachy(Filename: string);
+// TVNodeStack contains a path of TTreeNode for the last filename
+var
+  DelimPos: Integer;
+  FilePart: String;
+  Node: TTreeNode;
+  p: Integer;
+begin
+  p:=0;
+  while Filename<>'' do begin
+    // get the next file name part
+    DelimPos:=System.Pos(PathDelim,Filename);
+    if DelimPos>0 then begin
+      FilePart:=copy(Filename,1,DelimPos-1);
+      Filename:=copy(Filename,DelimPos+1,length(Filename));
+    end else begin
+      FilePart:=Filename;
+      Filename:='';
+    end;
+    //debugln(['ClearUnneededAndCreateHierachy FilePart=',FilePart,' Filename=',Filename,' p=',p]);
+    if p < fTVNodeStack.Count then begin
+      Node:=TTreeNode(fTVNodeStack[p]);
+      if (FilePart=Node.Text) and (Node.Data=nil) then begin
+        // same sub directory
+      end
+      else begin
+        // change directory => last directory is complete
+        // => delete unneeded nodes after last path
+        TVDeleteUnneededNodes(p+1);
+        if Node.GetNextSibling<>nil then begin
+          Node:=Node.GetNextSibling;
+          Node.Text:=FilePart;
+        end
+        else
+          Node:=fTreeview.Items.Add(Node,FilePart);
+        fTVNodeStack[p]:=Node;
+      end;
+    end else begin
+      // new sub node
+      if p>0 then
+        Node:=TTreeNode(fTVNodeStack[p-1])
+      else
+        Node:=fOwner.fRootNode;
+      if Node.GetFirstChild<>nil then begin
+        Node:=Node.GetFirstChild;
+        Node.Text:=FilePart;
+      end
+      else
+        Node:=fTreeview.Items.AddChild(Node,FilePart);
+      fTVNodeStack.Add(Node);
+    end;
+    if (Filename<>'') then begin
+      Node.ImageIndex:=fOwner.fImageIndexDirectory;
+      Node.SelectedIndex:=Node.ImageIndex;
+    end;
+    inc(p);
+  end;
+end;
+
+
+{ TViewControlListbox }
+
+constructor TViewControlListbox.Create(AOwner: TListFilterEdit; aListbox: TListbox);
+begin
+  inherited Create(AOwner);
+  fListbox:=aListbox;
+end;
+
+destructor TViewControlListbox.Destroy;
+begin
+  inherited Destroy;
+end;
+
+procedure TViewControlListbox.ApplyFilter;
+var
+  i: Integer;
+  FileN: string;
+begin
+  fListbox.Clear;
+  fListbox.Items.BeginUpdate;
+  with fOwner do
+    for i:=0 to fSortedData.Count-1 do begin
+      FileN:=fSortedData[i];
+      fListbox.Items.AddObject(FileN, fSortedData.Objects[i]);
+      if Assigned(fSelectedPart) then
+        fListbox.Selected[i]:=fSelectedPart=fSortedData.Objects[i];
+    end;
+  fListbox.Items.EndUpdate;
+end;
+
+procedure TViewControlListbox.StoreSelection;
+var
+  i: Integer;
+begin
+  for i := 0 to fListbox.Count-1 do begin
+    if fListbox.Selected[i] then
+      fOwner.fSelectionList.Add(fListbox.Items[i]);
+  end;
+end;
+
+procedure TViewControlListbox.RestoreSelection;
+var
+  i: Integer;
+begin
+  for i := 0 to fListbox.Count-1 do begin
+    if fOwner.fSelectionList.IndexOf(fListbox.Items[i])>0 then
+      fListbox.Selected[i]:=True;
+  end;
+end;
+
 
 { TListBoxFilterEdit }
 
@@ -175,7 +501,6 @@ constructor TListFilterEdit.Create(AOwner: TComponent);
 begin
   inherited Create(AOwner);
   fOriginalData:=TStringList.Create;
-  fSortedData:=TStringList.Create;
   fSelectionList:=TStringList.Create;
   fFilenameMap:=TStringToStringTree.Create(True);
   fImageIndexDirectory := -1;
@@ -185,15 +510,15 @@ begin
   OnChange:=@FilterEditChange;
   OnEnter:=@FilterEditEnter;
   OnExit:=@FilterEditExit;
+  fIsFirstUpdate:=True;
 end;
 
 destructor TListFilterEdit.Destroy;
 begin
-  FreeTVNodeData(fRootNode);
   fFilenameMap.Free;
   fSelectionList.Free;
-  fSortedData.Free;
   fOriginalData.Free;
+  fViewControlWrapper.Free;
   inherited Destroy;
 end;
 
@@ -206,9 +531,11 @@ begin
   if Index < 0 then Exit;
   ena:=True;
   ImgIndex:=-1;
-  if Assigned(fImages4Listbox) and Assigned(OnGetImageIndex) then
+  if Assigned(fImages4Listbox) and Assigned(OnGetImageIndex) then begin
+    ena:=True;
     ImgIndex:=OnGetImageIndex(fFilteredListbox.Items[Index],
                               fFilteredListbox.Items.Objects[Index], ena);
+  end;
   fFilteredListbox.Canvas.FillRect(ARect);
   if ImgIndex<>-1 then
   begin
@@ -294,6 +621,9 @@ begin
   if Assigned(fFilteredListbox) then
     raise Exception.Create('Sorry, both Treeview and ListBox should not be assigned.');
   fFilteredTreeview:=AValue;
+  if Assigned(fViewControlWrapper) then
+    fViewControlWrapper.Free;
+  fViewControlWrapper:=TViewControlTreeview.Create(Self, fFilteredTreeview);
 end;
 
 procedure TListFilterEdit.SetFilteredListbox(const AValue: TListBox);
@@ -301,15 +631,15 @@ begin
   if Assigned(fFilteredTreeview) then
     raise Exception.Create('Sorry, both Treeview and ListBox should not be assigned.');
   fFilteredListbox:=AValue;
-  if fFilteredListbox.Style=lbStandard then begin
+  if fFilteredListbox.Style<>lbStandard then begin
-    // ToDo: support normal drawing (lbStandard).
-  end
-  else begin
     if Assigned(fFilteredListbox.OnDrawItem) then
       raise Exception.Create('Listbox.OnDrawItem should not be defined.'+
                              ' ListFilterEdit assigns its own handler.');
     fFilteredListbox.OnDrawItem:=@ListBoxDrawItem;
   end;
+  if Assigned(fViewControlWrapper) then
+    fViewControlWrapper.Free;
+  fViewControlWrapper:=TViewControlListbox.Create(Self, fFilteredListbox);
 end;
 
 procedure TListFilterEdit.SetShowDirHierarchy(const AValue: Boolean);
@@ -325,262 +655,21 @@ begin
   fFilenameMap[ShortFilename]:=FullFilename;
 end;
 
-procedure TListFilterEdit.StoreTreeSelection;
-var
-  ANode: TTreeNode;
-begin
-  ANode:=fFilteredTreeview.Selected;
-  while ANode<>nil do begin
-    fSelectionList.Insert(0,ANode.Text);
-    ANode:=ANode.Parent;
-  end;
-end;
-
-procedure TListFilterEdit.StoreListSelection;
-var
-  i: Integer;
-begin
-  for i := 0 to fFilteredListbox.Count-1 do begin
-    if fFilteredListbox.Selected[i] then
-      fSelectionList.Add(fFilteredListbox.Items[i]);
-  end;
-end;
-
-procedure TListFilterEdit.RestoreTreeSelection;
-var
-  ANode: TTreeNode;
-  CurText: string;
-begin
-  ANode:=nil;
-  while fSelectionList.Count>0 do begin
-    CurText:=fSelectionList[0];
-    if ANode=nil then
-      ANode:=fFilteredTreeview.Items.GetFirstNode
-    else
-      ANode:=ANode.GetFirstChild;
-    while (ANode<>nil) and (ANode.Text<>CurText) do
-      ANode:=ANode.GetNextSibling;
-    if ANode=nil then break;
-    fSelectionList.Delete(0);
-  end;
-  if ANode<>nil then
-    fFilteredTreeview.Selected:=ANode;
-  fSelectionList.Clear;
-end;
-
-procedure TListFilterEdit.RestoreListSelection;
-var
-  i: Integer;
-begin
-  for i := 0 to fFilteredListbox.Count-1 do begin
-    if fSelectionList.IndexOf(fFilteredListbox.Items[i])>0 then
-      fFilteredListbox.Selected[i]:=True;
-  end;
-end;
-
-procedure TListFilterEdit.FreeTVNodeData(Node: TTreeNode);
-var
-  Child: TTreeNode;
-begin
-  if Node=nil then exit;
-  if (Node.Data<>nil) then begin
-    TObject(Node.Data).Free;
-    Node.Data:=nil;
-  end;
-  Child:=Node.GetFirstChild;
-  while Child<>nil do
-  begin
-    FreeTVNodeData(Child);
-    Child:=Child.GetNextSibling;
-  end;
-end;
-
-procedure TListFilterEdit.TVDeleteUnneededNodes(p: integer);
-// delete all nodes behind the nodes in the stack, and depth>=p
-var
-  i: Integer;
-  Node: TTreeNode;
-begin
-  for i:=fTVNodeStack.Count-1 downto p do begin
-    Node:=TTreeNode(fTVNodeStack[i]);
-    while Node.GetNextSibling<>nil do
-      Node.GetNextSibling.Free;
-  end;
-  fTVNodeStack.Count:=p;
-end;
-
-procedure TListFilterEdit.TVClearUnneededAndCreateHierachy(Filename: string);
-// TVNodeStack contains a path of TTreeNode for the last filename
-var
-  DelimPos: Integer;
-  FilePart: String;
-  Node: TTreeNode;
-  p: Integer;
-begin
-  p:=0;
-  while Filename<>'' do begin
-    // get the next file name part
-    DelimPos:=System.Pos(PathDelim,Filename);
-    if DelimPos>0 then begin
-      FilePart:=copy(Filename,1,DelimPos-1);
-      Filename:=copy(Filename,DelimPos+1,length(Filename));
-    end else begin
-      FilePart:=Filename;
-      Filename:='';
-    end;
-    //debugln(['ClearUnneededAndCreateHierachy FilePart=',FilePart,' Filename=',Filename,' p=',p]);
-    if p < fTVNodeStack.Count then begin
-      Node:=TTreeNode(fTVNodeStack[p]);
-      if (FilePart=Node.Text) and (Node.Data=nil) then begin
-        // same sub directory
-      end
-      else begin
-        // change directory => last directory is complete
-        // => delete unneeded nodes after last path
-        TVDeleteUnneededNodes(p+1);
-        if Node.GetNextSibling<>nil then begin
-          Node:=Node.GetNextSibling;
-          Node.Text:=FilePart;
-        end
-        else
-          Node:=fFilteredTreeview.Items.Add(Node,FilePart);
-        fTVNodeStack[p]:=Node;
-      end;
-    end else begin
-      // new sub node
-      if p>0 then
-        Node:=TTreeNode(fTVNodeStack[p-1])
-      else
-        Node:=fRootNode;
-      if Node.GetFirstChild<>nil then begin
-        Node:=Node.GetFirstChild;
-        Node.Text:=FilePart;
-      end
-      else
-        Node:=fFilteredTreeview.Items.AddChild(Node,FilePart);
-      fTVNodeStack.Add(Node);
-    end;
-    if (Filename<>'') then begin
-      Node.ImageIndex:=fImageIndexDirectory;
-      Node.SelectedIndex:=Node.ImageIndex;
-    end;
-    inc(p);
-  end;
-end;
-
-function TListFilterEdit.CompareFNs(AFilename1,AFilename2: string): integer;
-begin
-  if fSortData then
-    Result:=CompareFilenames(AFilename1, AFilename2)
-  else if fShowDirHierarchy then
-    Result:=CompareFilenames(ExtractFilePath(AFilename1), ExtractFilePath(AFilename2))
-  else
-    Result:=0;
-end;
-
-procedure TListFilterEdit.SortAndFilter;
-// Copy data from fOriginalData to fSortedData in sorted order
-var
-  Origi, i: Integer;
-  FileN: string;
-begin
-  fSortedData.Clear;
-  for Origi:=0 to fOriginalData.Count-1 do begin
-    FileN:=fOriginalData[Origi];
-    if (Filter='') or (Pos(Filter,lowercase(FileN))>0) then begin
-      i:=fSortedData.Count-1;
-      while i>=0 do begin
-        if CompareFNs(FileN,fSortedData[i])>=0 then break;
-        dec(i);
-      end;
-      fSortedData.InsertObject(i+1,FileN, fOriginalData.Objects[Origi]);
-    end;
-  end;
-end;
-
-procedure TListFilterEdit.ApplyFilterToTreeview;
-var
-  TVNode: TTreeNode;
-  ImgIndex, i: Integer;
-  FileN, s: string;
-  ena: Boolean;
-begin
-  ImgIndex:=-1;
-  if fSelectedPart=Nil then
-    StoreTreeSelection;
-  if fFilenameMap.Count > 0 then
-    FreeTVNodeData(fRootNode);   // Free node data now, it will be filled later.
-  if Assigned(fRootNode) then    // Delete old tree nodes.
-    fRootNode.DeleteChildren
-  else
-    fFilteredTreeview.Items.Clear;
-  if fShowDirHierarchy then
-    fTVNodeStack:=TFPList.Create;
-  fFilteredTreeview.BeginUpdate;
-  for i:=0 to fSortedData.Count-1 do begin
-    FileN:=fSortedData[i];
-    if fShowDirHierarchy then begin
-      TVClearUnneededAndCreateHierachy(FileN);
-      TVNode:=TTreeNode(fTVNodeStack[fTVNodeStack.Count-1]);
-    end
-    else if Assigned(fRootNode) then
-      TVNode:=fFilteredTreeview.Items.AddChild(fRootNode,FileN)
-    else
-      TVNode:=fFilteredTreeview.Items.Add(Nil,FileN);
-    if fFilenameMap.Count > 0 then begin
-      s:=FileN;
-      if fFilenameMap.Contains(FileN) then
-        s:=fFilenameMap[FileN];           // Full file name.
-      TVNode.Data:=TFileNameItem.Create(s);
-    end;
-    if Assigned(OnGetImageIndex) then
-      ImgIndex:=OnGetImageIndex(FileN, fSortedData.Objects[i], ena);
-    TVNode.ImageIndex:=ImgIndex;
-    TVNode.SelectedIndex:=ImgIndex;
-    if Assigned(fSelectedPart) then
-      TVNode.Selected:=fSelectedPart=fSortedData.Objects[i];
-  end;
-  if fShowDirHierarchy then      // TVDeleteUnneededNodes(0); ?
-    fTVNodeStack.Free;
-  if Assigned(fRootNode) then
-    fRootNode.Expanded:=True;
-  if fSelectedPart=Nil then
-    RestoreTreeSelection;
-  fFilteredTreeview.EndUpdate;
-end;
-
-procedure TListFilterEdit.ApplyFilterToListBox;
-var
-  i: Integer;
-  FileN: string;
-begin
-  if fSelectedPart=Nil then
-    StoreListSelection;
-  fFilteredListbox.Clear;
-  fFilteredListbox.Items.BeginUpdate;
-  for i:=0 to fSortedData.Count-1 do begin
-    FileN:=fSortedData[i];
-    fFilteredListbox.Items.AddObject(FileN, fSortedData.Objects[i]);
-    if Assigned(fSelectedPart) then
-      fFilteredListbox.Selected[i]:=fSelectedPart=fSortedData.Objects[i];
-  end;
-  if fSelectedPart=Nil then
-    RestoreListSelection;
-  fFilteredListbox.Items.EndUpdate;
-end;
-
 procedure TListFilterEdit.ApplyFilter(Immediately: Boolean);
 begin
   if Immediately then begin
-    fNeedUpdate:=false;
+    if not (Assigned(fFilteredTreeview) or Assigned(fFilteredListbox)) then
-    SortAndFilter;
-    if Assigned(fFilteredTreeview) then
-      ApplyFilterToTreeview
-    else if Assigned(fFilteredListbox) then
-      ApplyFilterToListBox
-    else
       raise Exception.Create(
         'Set either FilteredTreeview or FilteredListbox before using the filter.');
+    fNeedUpdate:=false;
+    fViewControlWrapper.SortAndFilter;
+    if (fSelectedPart=Nil) and not fIsFirstUpdate then
+      fViewControlWrapper.StoreSelection; // At first round the selection is from caller
+    if fIsFirstUpdate then
+      fIsFirstUpdate:=False;
+    fViewControlWrapper.ApplyFilter;
+    fSelectedPart:=Nil;
+    fViewControlWrapper.RestoreSelection;
   end
   else begin
     if csDestroying in ComponentState then exit;