Spalten bei der Listview zur Laufzeit ausblenden

[Bernd O]

Wie kann man zur Laufzeit Spalten(Columns) einer Listview ausblenden und dann nach bedarf wieder einblenden.
Hab die ganze Delphi Hilfe abgesucht, aber nichts brauchbares gefunden.

[Jens Schumann]

Hallo Bernd,<br>probier doch mal ListView1.Columns[iCnt].Width:=0;<br>:-) Jens schuman

[Bernd O]

Den Trick habe ich schon probiert, aber ist nicht ganz so sauber, da man die Columns wieder auseinanderziehen kann :O

Hallo Bernd,
hier ist eine Beispiel zu erste Column in einer Listview ausblenden und dann nach bedarf wieder einblenden.

unit MyListview;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,Commctrl,Comctrls;

type
TMyListView = class(TListview)
private
FUpdatingColumnOrder: Boolean;
FHeaderHandle: HWND;
FHeaderInstance: Pointer;
FDefHeaderProc: Pointer;
procedure WMNCCalcSize(Var msg : TMessage); message WM_NCCALCSIZE;
procedure WMNotify(var Message: TWMNotify); message WM_NOTIFY;
procedure WMParentNotify(var Message: TWMParentNotify); message WM_PARENTNOTIFY;
end;

type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
private
lListView : TMyListview;
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.DFM}

procedure TMyListView.WMNCCalcSize(Var msg : TMessage);
var Style : Integer;
begin
Style := getWindowLong(Handle, GWL_STYLE);
if (Style and WS_HSCROLL) <> 0
then SetWindowLong(Handle, GWL_STYLE,Style and not WS_HSCROLL);
inherited;
end; //TMyListView.WMNCCalcSize

procedure TMyListView.WMParentNotify(var Message: TWMParentNotify);
begin
with Message do
if (Event = WM_CREATE) and (FHeaderHandle = 0) then
begin
FHeaderHandle := ChildWnd;
FDefHeaderProc := Pointer(GetWindowLong(FHeaderHandle, GWL_WNDPROC));
SetWindowLong(FHeaderHandle, GWL_WNDPROC, LongInt(FHeaderInstance));
end;
inherited;
end; //TMyListView.WMParentNotify

procedure TMyListView.WMNotify(var Message: TWMNotify);
var
P: TPoint;
hChildWnd: HWND;
WndClass: string;
hdhti: THDHitTestInfo;
begin
if (Message.NMHdr^.hWndFrom = FHeaderHandle) then
with Message.NMHdr^ do begin
inherited;
case code of
HDN_BEGINTRACKA : begin
with PHDNotify(Pointer(Message.NMHdr))^, PItem^ do begin
if (Item = 0) then begin
Column[0].Width := 0;
Message.Result := 1;
end;
end;
end;
HDN_BEGINTRACKW : begin
with PHDNotify(Pointer(Message.NMHdr))^, PItem^ do begin
if (Item = 0) then begin
Column[0].Width := 0;
Message.Result := 1;
end;
end;
end;
HDN_ENDDRAG:
FUpdatingColumnOrder := True;
HDN_DIVIDERDBLCLICK:
with PHDNotify(Pointer(Message.NMHdr))^ do begin
if IsCustomDrawn(dtControl, cdPrePaint) then Invalidate;
end;
NM_RCLICK: begin
P := Point(LoWord(GetMessagePos), HiWord(GetMessagePos));
hChildWnd := ChildWindowFromPoint(Handle, ScreenToClient(P));
if (hChildWnd <> 0) and (hChildWnd <> Handle) then begin
SetLength(WndClass, 80);
SetLength(WndClass, GetClassName(hChildWnd, PChar(WndClass), Length(WndClass)));
if WndClass = 'SysHeader32' then begin
hdhti.Point := ScreenToClient(P);
if SendMessage(hChildWnd, HDM_HITTEST, 1, Longint(@hdhti)) >= 0
then ColRightClick(Column[hdhti.Item], hdhti.Point);
end;
end;
end;
end;
end;
end; // TMyListView.WMNotify

procedure TForm1.FormCreate(Sender: TObject);
var
lColumneu : TListColumn;
begin
lListview := TMyListview.Create(Self);
lListview.ParentWindow := Handle;
lListview.ViewStyle := vsReport;
With lListview do begin
Left := 0;
Top := 0;
Width:= 400;
Height := 400;
lColumneu := Columns.Add;
lColumneu.Caption := 'Test1';
lColumneu.Width := 200;
lColumneu := Columns.Add;
lColumneu.Caption := 'test2';
lColumneu.Width := 200;
Visible := TRUE;
end;
end;

end.
my E-Mail adresse : thietquy@hotmail.