我已经创建了一个示例组件下面。有3个TPanel s包含1个TImage。我希望图像按照代码中的指示绘制自己。这不会发生。
如果构建此组件并将其放到窗体上，则不会看到任何绘画，并且在执行时程序也不会显示任何绘画。
我在Windows 11机器上使用 Delphi 10.4。
我不知道我做错了什么。我尝试使用Paint方法，但这导致了一个循环错误。我只是从创建的组件的绘画命令中复制了相同的细节到Paint。不是一个好结果。

unit Schedule;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Classes, Vcl.Controls,
  Vcl.ExtCtrls, Vcl.Graphics, Vcl.StdCtrls, Vcl.Forms;

type
  TEBSSchedule = class(TCustomControl)
  private
    Panel1, Panel2, Panel3: TPanel;
    Image1, Image2, Image3: TImage;
    ScrollBar1, ScrollBar2: TScrollBar;

    procedure Image3MouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Image3MouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer);
    procedure Image3MouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);

    procedure CreatePanels;
    procedure CreateScrollBars;
  protected
    procedure Paint; override;
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
  end;

Procedure Register;

implementation

constructor TEBSSchedule.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  Width := 400;
  Height := 300;

  CreatePanels;
  CreateScrollBars;
end;

destructor TEBSSchedule.Destroy;
begin
  if Assigned(Image1) then Image1.Free;
  if Assigned(Image2) then Image2.Free;
  if Assigned(Image3) then Image3.Free;
  if Assigned(Panel1) then Panel1.Free;
  if Assigned(Panel2) then Panel2.Free;
  if Assigned(Panel3) then Panel3.Free;
  if Assigned(ScrollBar1) then ScrollBar1.Free;
  if Assigned(ScrollBar2) then ScrollBar2.Free;

  inherited Destroy;
end;

procedure TEBSSchedule.CreatePanels;
var
  T: TRect;
begin
  T.Left := 0;
  T.Top := 0;
  Panel1 := TPanel.Create(Self);
  Panel1.Parent := Self;
  Panel1.SetBounds(100,0,Self.Width-100,25);
  Panel1.Anchors := [akLeft,akTop,akRight];
  Image1 := TImage.Create(Panel1);
  Image1.Parent := Panel1;
  Image1.Align := alClient;
  Image1.Picture.Bitmap.Canvas.Brush.Color := clBlue;
  T.Right := Panel1.Width;
  T.Bottom := Panel1.Height;
  Image1.Picture.Bitmap.Canvas.FillRect(T);

  Panel2 := TPanel.Create(Self);
  Panel2.Parent := Self;
  Panel2.SetBounds(0,Panel1.Height,100,Self.Height-25);
  Panel2.Anchors := [akLeft,akTop,akBottom];
  Image2 := TImage.Create(Panel2);
  Image2.Parent := Panel2;
  Image2.Align := alClient;
  Image2.Picture.Bitmap.Canvas.Brush.Color := clBlue;
  T.Right := Panel2.Width;
  T.Bottom := Panel2.Height;
  Image2.Picture.Bitmap.Canvas.FillRect(T);

   Panel3 := TPanel.Create(Self);
  Panel3.Parent := Self;
  Panel3.SetBounds(Panel2.Width,Panel1.Height,
  Self.Width-Panel2.Width,Self.Height-Panel1.Height);
  Panel3.Anchors := [akLeft,akTop,akRight,akBottom];
  Image3 := TImage.Create(Panel3);
  Image3.Parent := Panel3;
  Image3.Align := alClient;
  Image3.Picture.Bitmap.Canvas.Brush.Color := clYellow;
  T.Right := Panel3.Width;
  T.Bottom := Panel3.Height;
  Image3.Picture.Bitmap.Canvas.FillRect(T);
  Image3.OnMouseDown := Image3MouseDown;
  Image3.OnMouseMove := Image3MouseMove;
  Image3.OnMouseUp := Image3MouseUp;
end;

procedure TEBSSchedule.CreateScrollBars;
begin
  ScrollBar1 := TScrollBar.Create(Self);
  ScrollBar1.Parent := Self;
  ScrollBar1.Kind := sbHorizontal;
  ScrollBar1.Align := alBottom;

  ScrollBar2 := TScrollBar.Create(Self);
  ScrollBar2.Parent := Self;
  ScrollBar2.Kind := sbVertical;
  ScrollBar2.Align := alRight;
end;

procedure TEBSSchedule.Paint;
begin
  inherited Paint;
end;

procedure TEBSSchedule.Image3MouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
end;

procedure TEBSSchedule.Image3MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
end;

procedure TEBSSchedule.Image3MouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
end;

procedure Register;
begin
  RegisterComponents('EBSH', [TEBSSchedule]);
end;

end.

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