Delphi 如何使用FireMonkey TCanvas.DrawXXX方法？

我试图创建一个带有自定义可视化的表单，但我无法使用最简单的TCanvas绘图方法。在以下示例中，我只能看到填充矩形，但没有直线和圆弧：

procedure TEditorPanel.FormPaint(Sender: TObject; Canvas: TCanvas; const ARect: TRectF);
var
  center, radius: TPointF;
  rect: TRectF;
begin
  with Canvas do
  begin
    Fill.Color := TAlphaColors.White;
    FillRect(RectF(0, 0, Width, Height), 0, 0, AllCorners, 1);

    center := PointF(200, 200);
    radius := PointF(40, 40);

    Stroke.Color := TAlphaColors.Red;
    Fill.Color := TAlphaColors.Blue;
    DrawLine(center, radius, 1);
    DrawArc(center, radius, 0, 90, 1);

    rect := RectF(10, 10, 100, 100);
    FillRect(rect, 0, 0, AllCorners, 100);
  end;
end;

---

我遗漏了什么？

如果您使用的是Delphi 10.1或更高版本，则应将

Stroke.Kind

设置为

TBrushKind.Solid

以获得显示的行，默认值为

None

：

var
  center, radius: TPointF;
  rect: TRectF;
begin
  with Canvas do
  begin
    Fill.Color := TAlphaColors.White;
    FillRect(RectF(0, 0, Width, Height), 0, 0, AllCorners, 1);

    center := PointF(200, 200);
    radius := PointF(40, 40);

    Stroke.Kind := TBrushKind.Solid;
    Stroke.Color := TAlphaColors.Red;
    Fill.Color := TAlphaColors.Blue;
    DrawLine(center, radius, 1);
    DrawArc(center, radius, 0, 90, 1);

    rect := RectF(10, 10, 100, 100);
    FillRect(rect, 0, 0, AllCorners, 100);
  end;

你看过这个q吗？