Delphi XE里面 SharedActivityContext 提示错误

使用歪果仁的unit

//--------------------

unit Android.JNI.Toast;

// Java bridge class imported by hand by Brian Long (http://blong.com)
interface

{$IFDEF ANDROID}

uses
Androidapi.JNIBridge,
Androidapi.JNI.JavaTypes,
Androidapi.JNI.GraphicsContentViewText;
{$ENDIF}
{$IFDEF ANDROID}

type
TToastLength = (LongToast, ShortToast);

JToast = interface;

JToastClass = interface(JObjectClass)
['{69E2D233-B9D3-4F3E-B882-474C8E1D50E9}']
{ Property methods }
function _GetLENGTH_LONG: Integer; cdecl;
function _GetLENGTH_SHORT: Integer; cdecl;
{ Methods }
function init(context: JContext): JToast; cdecl; overload;
function makeText(context: JContext; text: JCharSequence; duration: Integer)
: JToast; cdecl;
{ Properties }
property LENGTH_LONG: Integer read _GetLENGTH_LONG;
property LENGTH_SHORT: Integer read _GetLENGTH_SHORT;
end;

[JavaSignature('android/widget/Toast')]
JToast = interface(JObject)
['{FD81CC32-BFBC-4838-8893-9DD01DE47B00}']
{ Methods }
procedure cancel; cdecl;
function getDuration: Integer; cdecl;
function getGravity: Integer; cdecl;
function getHorizontalMargin: Single; cdecl;
function getVerticalMargin: Single; cdecl;
function getView: JView; cdecl;
function getXOffset: Integer; cdecl;
function getYOffset: Integer; cdecl;
procedure setDuration(value: Integer); cdecl;
procedure setGravity(gravity, xOffset, yOffset: Integer); cdecl;
procedure setMargin(horizontalMargin, verticalMargin: Single); cdecl;
procedure setText(s: JCharSequence); cdecl;
procedure setView(view: JView); cdecl;
procedure show; cdecl;
end;

TJToast = class(TJavaGenericImport<JToastClass, JToast>)
end;

procedure Toast(const Msg: string; duration: TToastLength = ShortToast);

{$ENDIF}

implementation

{$IFDEF ANDROID}

uses
FMX.Helpers.Android,
Androidapi.Helpers;//加上，否则SharedActivityContext提示错误，

procedure Toast(const Msg: string; duration: TToastLength);
var
ToastLength: Integer;
begin
if duration = ShortToast then
ToastLength := TJToast.JavaClass.LENGTH_SHORT
else
ToastLength := TJToast.JavaClass.LENGTH_LONG;
CallInUiThread(
procedure
begin
TJToast.JavaClass.makeText(SharedActivityContext, StrToJCharSequence(Msg),
ToastLength).show
end);
end;
{$ENDIF}

end.

//-------------------

在使用的页面：

uses
Android.JNI.Toast,

procedure TForm2.FormKeyUp(Sender: TObject; var Key: Word; var KeyChar: Char;
Shift: TShiftState);
begin
if (Key = vkHardwareBack) or (Key = vkEscape) then
begin
if IsFirstBack then
begin
IsFirstBack := False;
Key := 0;
Timer1.Enabled := True;
Toast('再按一次退出',ShortToast);
// Toast('再按一次退出',ShortToast);
end
else
begin
end;
end;
end;

窗体上（TForm2）Onkeyup-->FormKeyUp