BeginDeferWindowPos 和 DeferWindowPos、EndDeferWindowPos 是一组一起使用的函数, 可对一组窗口的位置、大小、Z 序等进行调整, 在 ExtCtrls 单元有用到.

---

下面先用常规方法实现对 Panel1 中的一组 Button 进行调整, 然后再用上面三个函数重新实现.

---

本例效果图:

---

代码文件:

---

unit Unit1;

interface

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls, ExtCtrls;

type

  TForm1 = class(TForm)

    Panel1: TPanel;

    Button1: TButton;

    Button2: TButton;

    Button3: TButton;

    Button4: TButton;

    RadioButton1: TRadioButton;

    RadioButton2: TRadioButton;

    procedure RadioButton1Click(Sender: TObject);

    procedure RadioButton2Click(Sender: TObject);

  end;

var

  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.RadioButton1Click(Sender: TObject);

var

  num,i: Integer;

  btn: TButton;

  L,T,W,H: Integer;

begin

  num := Panel1.ControlCount;

  L := ;

  T := ;

  W := (Panel1.ClientWidth - L * (num+)) div num;

  H := (Panel1.ClientHeight - T * (num+)) div num;

  for i :=  to num -  do

  begin

    if Panel1.Controls[i] is TButton then

    begin

      btn := TButton(Panel1.Controls[i]);

      btn.Left := L;

      btn.Top := (H + T) * i + T;

      btn.Width := W;

      btn.Height := H;

    end;

  end;

end;

procedure TForm1.RadioButton2Click(Sender: TObject);

var

  num,i: Integer;

  btn: TButton;

  L,T,W,H: Integer;

begin

  num := Panel1.ControlCount;

  L := ;

  T := ;

  W := (Panel1.ClientWidth - L * (num+)) div num;

  H := (Panel1.ClientHeight - T * (num+)) div num;

  for i :=  to num -  do

  begin

    if Panel1.Controls[i] is TButton then

    begin

      btn := TButton(Panel1.Controls[i]);

      btn.Left := (W + L) * i + L;

      btn.Top := T;

      btn.Width := W;

      btn.Height := H;

    end;

  end;

end;

end.

---