E2003 未声明的标识符：'mtConfirmation' 和 'mbOK'

Question

据我所知，这两个都应该在我正在使用的 System.UITypes 中，但我仍然收到错误消息。我该如何解决这个问题？

我已经基于 http://docwiki.embarcadero.com/CodeExamples/XE7/en/FileExists_(Delphi)

中示例的消息对话框

原码来自http://delphi.radsoft.com.au/2013/11/checking-for-an-internet-connection-on-mobile-devices-with-delphi-xe5/

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    Label1: TLabel;
    Label2: TLabel;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.fmx}

uses
  NetworkState;

procedure TForm1.Button1Click(Sender: TObject);
var
  NS: TNetworkState;
begin
  NS := TNetworkState.Create;
  try
    if not NS.IsConnected then begin
      MessageDlg(('No connection'), mtConfirmation, [mbOK], 0);
    end else if NS.IsWifiConnected then begin
      MessageDlg(('Wifi connection'), mtConfirmation, [mbOK], 0);
    end else if NS.IsMobileConnected then begin
      MessageDlg(('Mobile connection'), mtConfirmation, [mbOK], 0);
    end;
    Label2.Text := NS.CurrentSSID;
  finally
    NS.Free;
  end;
end;

end.

Answer 1

本单元的枚举类型为scoped。注意使用

{$SCOPEDENUMS ON}

就在单元的顶部。

The $SCOPEDENUMS directive enables or disables the use of scoped enumerations in Delphi code. More specifically, $SCOPEDENUMS affects only definitions of new enumerations, and only controls the addition of the enumeration's value symbols to the global scope.

In the {$SCOPEDENUMS ON} state, enumerations are scoped, and enum values are not added to the global scope. To specify a member of a scoped enum, you must include the type of the enum.

这意味着需要完全确定值的范围，就像这样

TMsgDlgType.mtConfirmation

像这样

TMsgDlgBtn.mbOK

等等。

E2003 未声明的标识符：'mtConfirmation' 和 'mbOK'

E2003 Undeclared identifier: 'mtConfirmation' and 'mbOK'

delphi

dialog

compiler-errors

delphi-xe7