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I have a problem with the quantity ListView

Posted on 2006-11-18
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Last Modified: 2011-09-20
I have a problem with the quantity ListView.

I cuts 62996 files to list

I want to save the list:

I uses

yew psvSaveDialog1.Execute then
begin
  writeComponentResFile (psvSaveDialog1.FileName, ListView);
end;
 
the time off save and open is too long

help me
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Question by:ProgsX
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1 Comment
 
LVL 9

Accepted Solution

by:
bernani earned 750 total points
ID: 17974565
Hi,

Maybe sth like this (If I remember well, the 2 procedures are coming from swissdelphicenter.ch.

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, ComCtrls;

type
  TForm1 = class(TForm)
    ListView1: TListView;
    Button1: TButton;
    Button2: TButton;
    ListView2: TListView;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Déclarations privées }
    procedure SaveListViewToFile(AListView: TListView; sFileName: string);
    procedure LoadListViewToFile(AListView: TListView; sFileName: string);
  public
    { Déclarations publiques }
  end;

var
  Form1: TForm1;

const
  Msg1 = 'File "%s" does not exist!';
  Msg2 = '"%s" is not a ListView file!';

implementation

{$R *.DFM}

procedure TForm1.SaveListViewToFile(AListView: TListView; sFileName: string);
var
  idxItem, idxSub, IdxImage: Integer;
  F: TFileStream;
  pText: PChar;
  sText: string;
  W, ItemCount, SubCount: Word;
  MySignature: array [0..2] of Char;
begin
  //Initialization
  with AListView do
  begin
    ItemCount := 0;
    SubCount  := 0;
    //****
    MySignature := 'PGX';
    //  ListViewFile
    F := TFileStream.Create(sFileName, fmCreate or fmOpenWrite);
    F.Write(MySignature, SizeOf(MySignature));

    if Items.Count = 0 then
      // List is empty
      ItemCount := 0
    else
      ItemCount := Items.Count;
    F.Write(ItemCount, SizeOf(ItemCount));

    if Items.Count > 0 then
    begin
      for idxItem := 1 to ItemCount do
      begin
        with Items[idxItem - 1] do
        begin
          //Save subitems count
          if SubItems.Count = 0 then
            SubCount := 0
          else
            SubCount := Subitems.Count;
          F.Write(SubCount, SizeOf(SubCount));
          //Save ImageIndex
          IdxImage := ImageIndex;
          F.Write(IdxImage, SizeOf(IdxImage));
          //Save Caption
          sText := Caption;
          w     := Length(sText);
          pText := StrAlloc(Length(sText) + 1);
          StrPLCopy(pText, sText, Length(sText));
          F.Write(w, SizeOf(w));
          F.Write(pText^, w);
          StrDispose(pText);
          if SubCount > 0 then
          begin
            for idxSub := 0 to SubItems.Count - 1 do
            begin
              //Save Item's subitems
              sText := SubItems[idxSub];
              w     := Length(sText);
              pText := StrAlloc(Length(sText) + 1);
              StrPLCopy(pText, sText, Length(sText));
              F.Write(w, SizeOf(w));
              F.Write(pText^, w);
              StrDispose(pText);
            end;
          end;
        end;
      end;
    end;
    F.Free;
  end;
end;



procedure TForm1.LoadListViewToFile(AListView: TListView; sFileName: string);
var
  F: TFileStream;
  IdxItem, IdxSubItem, IdxImage: Integer;
  W, ItemCount, SubCount: Word;
  pText: PChar;
  PTemp: PChar;
  MySignature: array [0..2] of Char;
  sExeName: string;
begin
  with AListView do
  begin
    ItemCount := 0;
    SubCount  := 0;

    sExeName := ExtractFileName(sFileName);

    if not FileExists(sFileName) then
    begin
      MessageBox(Handle, PChar(Format(Msg1, [sExeName])), 'I/O Error', MB_ICONERROR);
      Exit;
    end;

    F := TFileStream.Create(sFileName, fmOpenRead);
    F.Read(MySignature, SizeOf(MySignature));

    if MySignature <> 'PGX' then
    begin
      MessageBox(Handle, PChar(Format(Msg2, [sExeName])), 'I/O Error', MB_ICONERROR);
      Exit;
    end;

    F.Read(ItemCount, SizeOf(ItemCount));
    Items.Clear;

    for idxItem := 1 to ItemCount do
    begin
      with Items.Add do
      begin
        //Read imageindex
        F.Read(SubCount, SizeOf(SubCount));
        //Read imageindex
        F.Read(IdxImage, SizeOf(IdxImage));
        ImageIndex := IdxImage;
        //Read the Caption
        F.Read(w, SizeOf(w));
        pText := StrAlloc(w + 1);
        pTemp := StrAlloc(w + 1);
        F.Read(pTemp^, W);
        StrLCopy(pText, pTemp, W);
        Caption := StrPas(pText);
        StrDispose(pTemp);
        StrDispose(pText);
        if SubCount > 0 then
        begin
          for idxSubItem := 1 to SubCount do
          begin
            F.Read(w, SizeOf(w));
            pText := StrAlloc(w + 1);
            pTemp := StrAlloc(w + 1);
            F.Read(pTemp^, W);
            StrLCopy(pText, pTemp, W);
            Items[idxItem - 1].SubItems.Add(StrPas(pText));
            StrDispose(pTemp);
            StrDispose(pText);
          end;
        end;
      end;
    end;

    F.Free;
  end;
end;



procedure TForm1.Button1Click(Sender: TObject);
begin
  // Save Items and Clear the ListView
  SaveListViewToFile(ListView1, 'MyListView.sav');
  ListView1.Items.Clear;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
//avoid refresh
Listview1.Items.BeginUpdate;
//show it's performing
cursor:= crHourGlass;
  // Load Items
LoadListViewToFile(ListView1, 'MyListView.sav');
LoadListViewToFile(ListView2, 'MyListView.sav');
Listview1.Items.EndUpdate;
//show it's performing
cursor:= crDefault;
end;

end.

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