Nachricht NACH dem Löschen eines ListView.Item erhalten?

[Bummi]

Items.Count wird auch über eine Message abgerufen, zu einem Zeitpunkt zu dem das Messagehandling in dem Fall noch nicht abgeschlossen ist. "Ausbrechen" könnte man in der Art, zum weiterbasteln...

Delphi-Quellcode:

unit Unit2;

interface

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

  const
  WM_MyInfoMessage=WM_USER + 777;
type


  TListView=Class(comCtrls.TListView)
       private
    FOnItemDeleted: TNotifyEvent;
        procedure CNNotify(var Message: TWMNotifyLV); message CN_NOTIFY;
        Procedure MyInfomessage(var Message: TWMNotify);message WM_MyInfoMessage;
       published
        Property OnItemDeleted:TNotifyEvent read FOnItemDeleted write FOnItemDeleted;
  End;
  TForm2 = class(TForm)
    ListView1: TListView;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    procedure OnItemDel(sender: TObject);
    { Private-Deklarationen }

  public
    { Public-Deklarationen }
  end;

var
  Form2: TForm2;

implementation

{$R *.dfm}

{ TListView }



procedure TListView.CNNotify(var Message: TWMNotifyLV);
begin
   inherited;
   if (Message.NMHdr.code = LVN_DELETEITEM) or (Message.NMHdr.code = LVN_DELETEALLITEMS ) then
     if Message.Result=1 then
         begin
            PostMessage(Handle,WM_MyInfoMessage,0,0);
         end;
end;

procedure TForm2.Button1Click(Sender: TObject);
begin
  Showmessage('Before:'+IntToStr(ListView1.Items.Count));
  ListView1.Items.Delete(0);
end;

procedure TForm2.FormCreate(Sender: TObject);
begin
  ListView1.OnItemDeleted := OnItemDel;
end;

Procedure TForm2.OnItemDel(sender:TObject);
begin
   Showmessage('After:' + IntToStr(TListView(Sender).Items.Count));
end;

procedure TListView.MyInfomessage(var Message: TWMNotify);
begin
   if Assigned(FOnItemDeleted) then FOnItemDeleted(Self);


end;

end.