unit Unit1;

interface

uses
  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
  FMX.Types, FMX.Controls, FMX.Forms, FMX.Dialogs, Data.Bind.EngExt,
  Fmx.Bind.DBEngExt, Data.Bind.Components, FMX.Edit;

type
  TForm1 = class(TForm)
    TrackBar1: TTrackBar;
    Edit1: TEdit;
    Label1: TLabel;
    BindingsList1: TBindingsList;
    procedure FormCreate(Sender: TObject);
    procedure TrackBar1Change(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.fmx}

procedure TForm1.FormCreate(Sender: TObject);
begin
  {给 BindingsList1 添加表达式, 并设置参数}
  with TBindExpression.Create(BindingsList1) do
  begin
    ControlComponent := Edit1;    //目标控件
    ControlExpression := 'Text';  //目标控件属性
    SourceComponent := TrackBar1; //源控件
    SourceExpression := 'Value';  //源控件属性
    Active := True;               //激活; 可以通过 Active := False 断开绑定
  end;

  with TBindExpression.Create(BindingsList1) do
  begin
    ControlComponent := Label1;
    ControlExpression := 'Text';
    SourceComponent := TrackBar1;
    SourceExpression := 'Value';
    Active := True;
  end;
end;

{在 TrackBar1 的 OnChange 中发送通知}
procedure TForm1.TrackBar1Change(Sender: TObject);
begin
  BindingsList1.Notify(Sender, ''); //这里也可以写作: BindingsList1.Notify(TrackBar1, 'Value');
end;

end.

   ControlComponent : 'Edit1'
   ControlExpression: 'Text'
   SourceComponent  : 'TrackBar1'
   SourceExpression : 'Value'

unit Unit1;

interface

uses
  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
  FMX.Types, FMX.Controls, FMX.Forms, FMX.Dialogs, FMX.Edit;

type
  TForm1 = class(TForm)
    TrackBar1: TTrackBar;
    Edit1: TEdit;
    Label1: TLabel;
    procedure FormCreate(Sender: TObject);
    procedure TrackBar1Change(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.fmx}

uses System.Bindings.Expression, System.Bindings.Helper;

procedure TForm1.FormCreate(Sender: TObject);
begin
  TBindings.CreateManagedBinding(
    [TBindings.CreateAssociationScope([Associate(TrackBar1, 'Input1')])],
    'Input1.Value',
    [TBindings.CreateAssociationScope([Associate(Edit1, 'Output1')])],
    'Output1.Text',
    nil
  ); //其中的 Input1、Output1 都是随意的, 前后一致即可

  TBindings.CreateManagedBinding(
    [TBindings.CreateAssociationScope([Associate(TrackBar1, 'Input1')])],
    'Input1.Value',
    [TBindings.CreateAssociationScope([Associate(Label1, 'Output1')])],
    'Output1.Text',
    nil
  );
end;

procedure TForm1.TrackBar1Change(Sender: TObject);
begin
  TBindings.Notify(Sender, '');
end;

end.