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copied!<p>You may be better off doing this through careful use of the Align property.</p> <p>If I have three panels with alignments as indicated here:</p> <pre><code>|-----------------------| | | | alTop | | | |-----------------------| |-----------------------| | | | alTop | | | |-----------------------| |-----------------------| | | | alTop | | | |-----------------------| </code></pre> <p>And I delete the second one, then the third one will automatically pop into it's place.</p> <p>Just place all three panels inside another parent control (i.e., another panel) to define what "top" means when we say "alTop".</p> <p>If you want to animate the effect, then you'll have to be slightly fancier. Is that your goal? If so, I'm sure we can come up with something.</p> <p><strong>Edit - I wrote some code that may give you some ideas:</strong></p> <pre><code>unit Main; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls, Buttons, ExtCtrls; type TWhere = (wAtBeginning, wAtEnd); type TfrmMain = class(TForm) panCtrl: TPanel; panHost: TPanel; btnAddPan: TBitBtn; btnDelPan: TBitBtn; lbAddWhere: TListBox; lbDelWhere: TListBox; procedure btnAddPanClick(Sender: TObject); procedure FormShow(Sender: TObject); procedure btnDelPanClick(Sender: TObject); private function GetPanel(HostPanel: TPanel; Where: TWhere): TPanel; function BottomOfLastPanel(HostPanel: TPanel): integer; procedure AddPanel(HostPanel: TPanel; AddWhere: TWhere); procedure DelPanel(HostPanel: TPanel; DelWhere: TWhere); procedure DelThisPanel(Sender: TObject); end; var frmMain: TfrmMain; implementation {$R *.dfm} procedure TfrmMain.AddPanel(HostPanel: TPanel; AddWhere: TWhere); var pnl: TPanel; btn: TBitBtn; begin pnl := TPanel.Create(HostPanel); with pnl do begin case AddWhere of wAtBeginning: Top := 0; wAtEnd: Top := BottomOfLastPanel(HostPanel); end; Align := alTop; Parent := HostPanel; Caption := DateTimeToStr(Now); end; btn := TBitBtn.Create(pnl); with btn do begin Parent := pnl; Left := 0; Top := 0; Width := 100; Height := 30; Align := alLeft; Caption := 'Delete this panel'; OnClick := DelThisPanel; end; end; function TfrmMain.BottomOfLastPanel(HostPanel: TPanel): integer; begin //scan through all panels contained inside the host panel //return the bottom of the lowest one (highest "top" value) Result := 0; if Assigned(GetPanel(HostPanel,wAtEnd)) then begin Result := GetPanel(HostPanel,wAtEnd).Top + GetPanel(HostPanel,wAtEnd).Height; end; end; procedure TfrmMain.btnAddPanClick(Sender: TObject); begin case lbAddWhere.ItemIndex of 0: AddPanel(panHost,wAtBeginning); 1: AddPanel(panHost,wAtEnd); end; end; procedure TfrmMain.btnDelPanClick(Sender: TObject); begin case lbDelWhere.ItemIndex of 0: DelPanel(panHost,wAtBeginning); 1: DelPanel(panHost,wAtEnd); end; end; procedure TfrmMain.DelPanel(HostPanel: TPanel; DelWhere: TWhere); var pnlToDelete: TPanel; begin case DelWhere of wAtBeginning: pnlToDelete := GetPanel(HostPanel,wAtBeginning); wAtEnd: pnlToDelete := GetPanel(HostPanel,wAtEnd); end; if Assigned(pnlToDelete) then begin FreeAndNil(pnlToDelete); end; end; procedure TfrmMain.DelThisPanel(Sender: TObject); var parentPnl: TPanel; begin //delete the parent panel of this button if Sender is TBitBtn then begin if (Sender as TBitBtn).Parent is TPanel then begin parentPnl := (Sender as TBitBtn).Parent as TPanel; parentPnl.Parent := nil; FreeAndNil(parentPnl); end; end; end; procedure TfrmMain.FormShow(Sender: TObject); begin lbAddWhere.ItemIndex := 1; lbDelWhere.ItemIndex := 1; end; function TfrmMain.GetPanel(HostPanel: TPanel; Where: TWhere): TPanel; var i: integer; begin Result := nil; for i := 0 to panHost.ControlCount - 1 do begin if panHost.Controls[i] is TPanel then begin Result := (panHost.Controls[i] as TPanel); if Where = wAtBeginning then begin Break; end; end; end; end; end. </code></pre> <p><strong>And here is the code for the DFM:</strong></p> <pre><code>object frmMain: TfrmMain Left = 0 Top = 0 Caption = 'Add / Delete Panel Demo' ClientHeight = 520 ClientWidth = 637 Color = clBtnFace Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -11 Font.Name = 'Tahoma' Font.Style = [] OldCreateOrder = False OnShow = FormShow PixelsPerInch = 96 TextHeight = 13 object panCtrl: TPanel Left = 0 Top = 0 Width = 305 Height = 520 Align = alLeft TabOrder = 0 object btnAddPan: TBitBtn Left = 8 Top = 8 Width = 125 Height = 75 Caption = 'Add panel' TabOrder = 0 OnClick = btnAddPanClick end object btnDelPan: TBitBtn Left = 8 Top = 89 Width = 125 Height = 75 Caption = 'Remove panel' TabOrder = 1 OnClick = btnDelPanClick end object lbAddWhere: TListBox Left = 139 Top = 8 Width = 150 Height = 75 Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -13 Font.Name = 'Tahoma' Font.Style = [] ItemHeight = 16 Items.Strings = ( 'Add to the top' 'Add to the bottom') ParentFont = False TabOrder = 2 end object lbDelWhere: TListBox Left = 139 Top = 89 Width = 150 Height = 75 Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -13 Font.Name = 'Tahoma' Font.Style = [] ItemHeight = 16 Items.Strings = ( 'Delete from the top' 'Delete from the bottom') ParentFont = False TabOrder = 3 end end object panHost: TPanel Left = 305 Top = 0 Width = 332 Height = 520 Align = alClient TabOrder = 1 ExplicitLeft = 392 ExplicitTop = 264 ExplicitWidth = 185 ExplicitHeight = 41 end end </code></pre>

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