qow 17: (QUICKY) how to fill a treeview with a directorytree?

warum nur 50 Punkte ;-))))))

// why do spend only 50 Points ?

Cesario

HI, meikl,
Would you mind to formulate your qow more explicitly:
1. we already have the directory tree (some sort of outline)
and want simply copy it to treeview.
2. we have a name of some directory and want to fill the treeview with all the subdirectories of this directory?
Sincerely,
Nestorua.

cesario,
as NEW top15 member,
you will get no point from this q

well, why i spent so low points?
qows comes periodically each week one,
sometimes (i tend to do this more often)
i provide for each different
solution the same points,
therefore i must care
about my points-account
(sometimes i may have ask a q for myself)

well, why qows?
it was just an idea
- for providing points for none top15 members
- for learning from each other
- for a better community here
- for just for fun
... and more benefits

well,
and don't worry,
i run not out of ?simple questíons :-)))

meikl ;-)

to nestorua,

use the ttreeview and try to populate it with the directory structure of drive c:\ (for example)


to raidos,
looks good

meikl ;-)

(i'm not quick enough) :-))

to nestorua,
i will try on the next qow
to be clearer with the question
(i was a bit in hurry by this one)
meikl ;-)

procedure Populate(aTreeView: TTreeView; aRoot: TTreeNode;Path: string; Recurse: boolean);
var
  NewNode: TTreeNode;
  SRec: TSearchRec;
begin
  if FindFirst(Path + '*.*', SysUtils.faAnyFile, SRec) = 0 then
  repeat
    if (sRec.Name = '.') or (sRec.Name = '..') then
      Continue;
    NewNode := aTreeView.Items.AddChild(aRoot, SRec.Name);
    if Recurse and ((srec.Attr and sysutils.faDirectory) <> 0) then
      Populate(aTreeView, NewNode, Path + srec.name + '\', True);
  until
    FindNext(SRec) <> 0;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
Populate(TreeView1, nil, 'c:\', True);
end;

Hi meikl,
hi all.

I'm glad that qow problem was succesfully solved. Can I provide my sample for no-points?

----
Igor

sure, igor, you can provide your sample

i'm also happy that i can go on

meikl ;-)

Ok, then there is my version. It allow to scan drives and place result into TTreeView.


//  An advantage of this technique is that user able to work with directories
//  tree and see which of branches can be expanded while scanning is in progress
//  Once user click on node, and directory still not scanned, priority of
//  according thread increased to allow user see result of scanning ASAP.
//  Scanned and "in progress" directories shown in different colors.

sample application can be found at:
http://i-g-o-r.virtualave.net/zip/drivescan.zip

-----
Igor.

//------------------------------------------------------------------------------
//
//  Basic classes to background scan drive's directory using threads
//
//------------------------------------------------------------------------------
unit DSClasses;

interface

uses
  Classes, SysUtils, ComCtrls;

//------------------------------------------------------------------------------
type
  TScanThread = class(TThread)
  private
    FNode: TTreeNode;      // parent node of TreeView to include directories
    FTreeView: TTreeView;  // TreeView that keeps direcoris tree
    FPath: String;         // current path to scan
    FStrings: TStrings;    // TStringList to show info about running threads
                           // and keep references to allow termination
    FFoundDir: String;     // used as parameter for ScanSubdirectory method
    FExtCounter: ^Integer; // pointer to processed directories count
  protected
    procedure Execute; override;
    procedure ScanSubdirectory;
    procedure RemoveInfoFromListBox;
  public
    // APath - path to scan without backslash
    // ATreeView - control to place result
    // ANode - parent directory node
    // AStrings - keep all currently running threads
    // ACount - point to counter (Integer type) of processed directories
    constructor Create(const APath: String; ATreeView: TTreeView;
      ANode: TTreeNode; AStrings: TStrings; ACount: Pointer);
    destructor Destroy; override;
  end;

//------------------------------------------------------------------------------
implementation

//------------------------------------------------------------------------------
//
//          TScanThread
//
//------------------------------------------------------------------------------
constructor TScanThread.Create(const APath: String; ATreeView: TTreeView;
  ANode: TTreeNode; AStrings: TStrings; ACount: Pointer);
begin
  Inherited Create(True);

  FNode := ANode;

  // mark node as "in progress"
  if FNode <> nil then
    FNode.Data := Self;

  FPath := APath;
  FTreeView := ATreeView;
  FStrings := AStrings;
  FExtCounter := ACount;
  inc(FExtCounter^);

  FreeOnTerminate := True;

  // make it lowest to allow increase it in runtime when user needs
  // to scan directory ASAP (TreeView's node clicked)
  Priority := tpLowest;

  FStrings.AddObject(FPath, Self);

  Resume;
end;

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
destructor TScanThread.Destroy;
begin
  if (FNode <> nil) then
  begin
    if not Terminated then
    begin
      // mark node as "ready"
      FNode.Data := nil;
      FTreeView.Invalidate;
    end
    else
      // mark node as "terminated"
      FNode.Data := Pointer(-1);
  end;
  Inherited;
end;

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
procedure TScanThread.Execute;
var
  SR: TSearchRec;
begin
  if FindFirst(FPath+'\*.*', faDirectory, SR) = 0 then
  try
    repeat
      if (SR.Attr and faDirectory <>0) and (Copy(SR.Name, 1, 1) <> '.') then
      begin
        FFoundDir := SR.Name;
        Synchronize(ScanSubdirectory);
      end;
    until (FindNext(SR) <> 0) or Terminated;
  finally
    FindClose(SR)
  end;
  Synchronize(RemoveInfoFromListbox);
end;

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
procedure TScanThread.ScanSubdirectory;
var
  ST: TScanThread;
begin
  // if thread was terminated, then do not allow to run "child" thread
  if not Terminated then
    ST := TScanThread.Create(FPath + '\' + FFoundDir, FTreeView,
      FTreeView.Items.AddChild(FNode, FFoundDir), FStrings, FExtCounter);
end;

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
procedure TScanThread.RemoveInfoFromListBox;
begin
  try
    FStrings.Delete(FStrings.IndexOfObject(Self))
  except

  end;
end;

end.

hi meikl,
"am starting a new quest: qow = question of the week :-)"

actually its 4 mnts old now mmm are you cuting and pasting the header
i see you got your 25 point problem sorted :)


igor,
your screensaver from last time was quite impressive,just like the real thing.messing with the maths had some interesting effects ,like a laser show from top left corner etc :-)

>are you cuting and pasting the header
yes, i'm too lazy

yep Barry, something like laser....
I'v got enexpected results making samples for qow, may be it is one of reason why I like this quest :-)

HI, meikl,
Here is my solution.

unit frmMain;
{---------------------------------------------}
INTERFACE
{---------------------------------------------}
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls, ComCtrls, ImgList, ToolWin;

type
  TFormMain = class(TForm)
    tvAllDirs: TTreeView;
    CoolBar1: TCoolBar;
    tbMain: TToolBar;
    ToolButton1: TToolButton;
    tbFillTreeView: TToolButton;
    ToolButton3: TToolButton;
    tbEXIT: TToolButton;
    ToolButton5: TToolButton;
    ImageList1: TImageList;
    procedure tvAllDirsExpanded(Sender: TObject; Node: TTreeNode);
    procedure tbEXITClick(Sender: TObject);
    procedure tbFillTreeViewClick(Sender: TObject);
  private
    function GetOneLevelNode(ParentNode: TTreeNode; tv: TTreeView): boolean;
    procedure FillTreeViewWithDriveNames(tv: TTreeView);
    function GetPathFromNode(Node: TTreeNode): string;
    { Private declarations }
  public
    { Public declarations }
  end;

var
  FormMain: TFormMain;

{--------------------------------------------------}
IMPLEMENTATION
{--------------------------------------------------}

{$R *.dfm}
{---------------------------------------------------}
function TFormMain.GetOneLevelNode(ParentNode: TTreeNode; tv: TTreeView): boolean;
var lpFileName: PChar;
    lpFindFileData: TWIN32FindData;
    h: THandle;
    HasSibling: boolean;
{---}
procedure AddChildNode;
var Node: TTreeNode;
begin
  with lpFindFileData do
   if ((dwFileAttributes=FILE_ATTRIBUTE_DIRECTORY) and
       (String(cFileName)<>'.') and (String(cFileName)<>'..'))
    then
     with tv.Items.AddChild(ParentNode, String(cFileName)+'\') do
       begin
        ImageIndex:=2;
        SelectedIndex:=3;
       end;
end;
{---}
begin
   Result:=False;
//
   lpFileName:=PChar(GetPathFromNode(ParentNode)+'*.*');
   h:=FindFirstFile(lpFileName, lpFindFileData);
//
   if h=INVALID_HANDLE_VALUE
    then EXIT
    else AddChildNode;
//
   HasSibling:=FindNextFile(h, lpFindFileData);
   while HasSibling do
    begin
      AddChildNode;
      HasSibling:=FindNextFile(h, lpFindFileData);
    end;
//
   ParentNode.AlphaSort;
//
   Result:=ParentNode.HasChildren;
end;
{------------------------------------------------------}
procedure TFormMain.FillTreeViewWithDriveNames(tv: TTreeView);
var nLength,
    nBufferLength: integer;
    lpBuffer,
    lpDriveName: PAnsiChar;
    Node: TTreeNode;
begin
  nBufferLength:=254;
  GetMem(lpBuffer, nBufferLength+1);
  nLength:=GetLogicalDriveStrings(nBufferLength, lpBuffer);
//
  lpDriveName:=lpBuffer;
//
  while nLength>0 do
   begin
     Node:=tv.Items.Add(NIL, lpDriveName);
     Node.ImageIndex:=2;
     Node.SelectedIndex:=3;

     if GetDriveType(lpDriveName)=DRIVE_FIXED
      then GetOneLevelNode(Node, tv);
//
    nLength:=nLength-Length(lpDriveName)-1;
    lpDriveName:=lpDriveName+Length(lpDriveName)+1;
   end;
//
  FreeMem(lpBuffer);
end;
{---------------------------------------------------}
procedure TFormMain.tvAllDirsExpanded(Sender: TObject; Node: TTreeNode);
var ChildNode: TTreeNode;
begin
  ChildNode:=Node.getFirstChild;
  while ChildNode<>NIL do
   begin
     GetOneLevelNode(ChildNode, tvAllDirs);
     ChildNode:=Node.GetNextChild(ChildNode);
   end;
end;
{-------------------------------------------------}
function TFormMain.GetPathFromNode(Node: TTreeNode): string;
begin
  Result:='';
//
  if Node=NIL
   then EXIT;
//
  Result:=GetPathFromNode(Node.Parent)+Node.Text;
end;
{--------------------------------------------------}
procedure TFormMain.tbEXITClick(Sender: TObject);
begin
  Close;
end;
{--------------------------------------------------}
procedure TFormMain.tbFillTreeViewClick(Sender: TObject);
begin
  tvAllDirs.Items.Clear;
  FillTreeViewWithDriveNames(tvAllDirs);
end;
{-------------------------------------------------}
END.
Sincerely,
Nestorua.

seems i have to provide some extra points :-))

well, if all agree, i will grade as follows

raidos - 50 pts - this q raised to 50 pts
ginsonic - 25 pts - extra question
nestorua - 25 pts - extra question
igor - nothing :-)

may this ok?

meikl ;-)

You can keep my points for futhers qow ( I know that you need these ;-) ). I put my comment just to test me .

Regards,
NIck

P.S. About points sponsor problem . I think that if we contact Moondancer , she/he can move couple points from my account to your's .

well, no pints for ginsonic :-)

>I think that if we contact Moondancer , she/he can move
>couple points

could be, that SHE could help, but
i will wait to do this,
until the last moment

even as i'm kpro member my points should
be raised until 500 each month, and if i for myself has no q, it should be enough for the qows (i hope)
(thats are 20 gradings á 25 pts.)

another point would be to raise the points for a qow to 50 pts, then i will have a problem, but the qows would be still more attractive

but at the moment i leave as it is

meikl ;-)

OK then . When need my support I will be glad to help you . See you on net .

I agree with no points :-)

well raidos,

points increased to 50

nestu... (name not in mind)
an additional question will be posted for you

thanks for participating

next qow next monday,
because i was/am absent until then

meikl ;-)

well I want to populat a treeview with just a list of the directorys and I want to be able to populat a listview withe the coorisponding files...how do i do that