https://community.embarcadero.com/blogs?view=entry&id=9074

 

unit TabBadgeFrm; interface uses  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,  FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, FMX.TabControl, FMX.Controls.Presentation, FMX.Edit,  FMX.EditBox, FMX.SpinBox, FMX.StdCtrls, FMX.Layouts, FMX.ListBox,  FMX.NumberBox; type  TForm16 = class(TForm)    TabItem1: TTabItem;    TabItem2: TTabItem;    BadgeItem: TTabItem;    SpinBox1: TSpinBox;    ToolBar1: TToolBar;    Switch1: TSwitch;    ListBox1: TListBox;    ListBoxItem1: TListBoxItem;    ToolLabel: TLabel;    TabControl1: TTabControl;    procedure BadgeItemPaint(Sender: TObject; Canvas: TCanvas; const ARect: TRectF);    procedure SpinBox1Change(Sender: TObject);    procedure FormCreate(Sender: TObject);    procedure Switch1Switch(Sender: TObject);    procedure StepperUpClick(Sender: TObject);  private    FBadge: Integer;    FShowBadge: Boolean;    procedure SetBadge(const Value: Integer);    procedure SetShowBadge(const Value: Boolean);    {
     Private declarations }  public    {
     Public declarations }    property Badge: Integer read FBadge write SetBadge;    property ShowBadge: Boolean read FShowBadge write SetShowBadge;  end; var  Form16: TForm16; implementation {
    $R *.fmx}{
    $R *.iPhone55in.fmx IOS} procedure DrawBadge(Canvas: TCanvas; const ARect: TRectF; const Text: string;  const Color: TAlphaColor = TAlphaColorRec.Red);const  Padding = 2;  HorzTextMargin = 6;  VertTextMargin = 4;var  R: TRectF;  TextSize: TSizeF;  Brush: TBrush;  BadgeRadius: Single;begin  Canvas.Font.Size := 12;  // Measure text width  TextSize := TSizeF.Create(Canvas.TextWidth(Text), Canvas.TextHeight(Text));  // Calculate badge rect  R := TRectF.Create(0, 0, HorzTextMargin * 2 + TextSize.Width, VertTextMargin * 2 + TextSize.Height);  if R.Width < R.Height then    R.Width := R.Height;  // Position rect  R := TRectF.Create(ARect.Right - R.Width, ARect.Top, ARect.Right, ARect.Top + R.Height);  R.Offset(-Padding, Padding);  // Draw badge  BadgeRadius := R.Height / 2;  Brush := TBrush.Create(TBrushKind.Solid, Color);  try    Canvas.FillRect(R, BadgeRadius, BadgeRadius, AllCorners, 1, Brush);  finally    Brush.Free;  end;  // Draw text  Canvas.Fill.Color := TAlphaColorRec.White;  Canvas.FillText(R, Text, False, 1, [], TTextAlign.Center, TTextAlign.Center);end; procedure TForm16.BadgeItemPaint(Sender: TObject; Canvas: TCanvas; const ARect: TRectF);begin  if ShowBadge then    DrawBadge(Canvas, ARect, FBadge.ToString);end; procedure TForm16.FormCreate(Sender: TObject);begin  FBadge := 1;end; procedure TForm16.SetBadge(const Value: Integer);begin  if FBadge  Value then  begin    FBadge := Value;    BadgeItem.Repaint;  end;end; procedure TForm16.SetShowBadge(const Value: Boolean);begin  if FShowBadge  Value then  begin    FShowBadge := Value;    BadgeItem.Repaint;  end;end; procedure TForm16.SpinBox1Change(Sender: TObject);begin  Badge := Trunc(SpinBox1.Value);end; procedure TForm16.StepperUpClick(Sender: TObject);begin  Badge := Trunc(SpinBox1.Value);end; procedure TForm16.Switch1Switch(Sender: TObject);begin  ShowBadge := Switch1.IsChecked;end; end.