delphi - delphi组件顺序和图层选项

Question

我是delphi编程的新手：(
我正在尝试制作具有透明背景层和圆形顶层的自定义组件。但是，将以下代码添加到表单时，效果很好。
除了存在另一个组件的事实与自定义组件重叠或位于其之上之外，它位于下方且未显示。
我在下面尝试过一种形式

 BadgeTest1.BringToFront;
 BadgeTest1.ComponentIndex:=2;
 IndexVal:= BadgeTest1.ComponentIndex;

但是，仍然不起作用。无论如何，自定义组件是否可以显示在其他组件之上？只有圆形部分？
另外，我一直在尝试在自定义组件的中心（水平和垂直）放置标题，并尝试使用TextOut（）过程。如果有更好的选择，请让我知道吗？
以下是我的自定义组件BadgeTest的代码。
请帮忙，
非常感谢！

type
 TBadgeTest=class(TGraphicControl)

private
  FCaption:TCaption;
  FColor:TColor;
  FLayers:TLayerCollection;
  FHeight:Integer;
  FWidth:Integer;

protected
 procedure Paint; override;  
  procedure SetBkgLayer;      
  procedure SetSecondLayer;       
public
  constructor Create(AOwner: TComponent); override;
  destructor Destroy; override;
published
  property Caption:TCaption read FCaption write FCaption; 
end;

procedure Register;

implementation

  procedure Register;
begin
  RegisterComponents('Sample', [TBadgeTest]);
end;

constructor TBadgeTest.Create(AOwner: TComponent);
var
  ACanvas:TcxCanvas;
   begin
   inherited;
   FHeight:=20;
  Self.Height:=FHeight;
  Constraints.MaxHeight:=20;
  Constraints.MinHeight:=20;
  FHeight:=20;
  Self.Width:=FWidth;
  Constraints.MaxWidth:=20;
  Constraints.MinWidth:=20;
end;

destructor TBadgeTest.Destroy;
begin
  inherited;
end;

 procedure TBadgeTest.SetBkgLayer;   
 var
  Bitmap:TBitmap32;
  Layer: TCustomLayer;
 begin
  FLayers := TLayerCollection.Create(Self);
  Layer := FLayers.Add(TBitmapLayer);
  Layer.Index:=0;
  Bitmap:= TBitmap32.Create;
  Bitmap.DrawMode:=dmOpaque;
  Bitmap.SetSize(Width, Height);
  Bitmap.clear($00000000);

  Bitmap.Canvas.Pen.Width:=0;
  Bitmap.Canvas.Brush.Color:=$00107EFF;
  Bitmap.Canvas.Brush.Style:=bsClear;
  Bitmap.Canvas.Ellipse(Rect(0,0,20,20));
end;

  procedure TBadgeTest.SetSecondLayer;
var
  Bitmap:TBitmap32;
  Layer: TCustomLayer;
 begin
  Layer := FLayers.Add(TBitmapLayer);
  Layer.Index:=1;
  Layer.LayerOptions:= LOB_VISIBLE;
  Bitmap:=TBitmap32.Create;
  Bitmap.DrawMode:=dmCustom;
  Bitmap.SetSize(Width, Height);
  Bitmap.clear($00000000);

  Bitmap.Canvas.Pen.Width:=0;
  Bitmap.Canvas.Brush.Color:=$00107EFF;   //FF7E10
  Bitmap.Canvas.Brush.Style:=bsSolid;
  Bitmap.Canvas.Ellipse(Rect(0,0,Self.Width,Self.Height));

  Layer.BringToFront;
  Layer.BringToFront;
  //Layer.Scaled:=true;
  //  Layer.Bitmap:=Bitmap;
  end;

    procedure TBadgeTest.Paint;
var
    R:TRect;
    borderColor : Integer;
    fillCircle : Integer;  
    fontColor : Integer;  
    fontSize : Integer;   
    Bitmap:TBitmapImage;
  const
  _FF7E10_COLOR:Integer = $00107EFF; //#FF7E10           

 begin
  inherited;
  borderColor:=_FF7E10_COLOR;
  fillCircle:=_FF7E10_COLOR;

  Canvas.Pen.Create;
  Canvas.Pen.Style:=psClear;
  Canvas.Pen.Color:=borderColor;
  Canvas.Pen.Width:=0;

  SetBkgLayer;
  SetSecondLayer;

  Canvas.Brush.Create;
  Canvas.Brush.Style:= bsClear;
  Canvas.Brush.Color:=fillCircle;
  Canvas.Ellipse(0,0,Self.Width,Self.Height);
  Canvas.Font.Color:=clWhite;
  Canvas.Font.Name:='Arial';
  Canvas.Font.Size:=8;
  Canvas.Font.Quality := fqNonAntialiased;
  Canvas.Font.Style := [fsBold];

  R.Create(0, 0, Self.Width, Self.Height);
  //DrawText(Canvas.Handle, PChar(FCaption), -1, R, vaCenter);
 // Canvas.DrawText(FCaption, R, taCenter, vaCenter, False, False);
  Canvas.TextOut(5, 5, FCaption);
  //SetTextAlign(Canvas.Handle, ta_center);
  //DrawText(Canvas.Handle, PChar(FCaption),
  //R.Create(1, 10, 2, 26);
   //  Self.Width := Canvas.TextWidth(FCaption) + 30;
end;

Answer 1

TGraphicControl没有窗口句柄，仅在其父DC上绘制。
您不能将TGraphicContol放在TWinContol后代（例如TPanel，TButton，TEdit等）的前面。

请使用可以放在其他子TWinControl前面的TWinControl descendant as shown in your previous question，或以避免出现其他TWinControl与自定义图形控件重叠或重叠的方式重新设计UI。

P.S：视觉控件被称为“控件”，而不是“组件”（非视觉）