uses здесь лишние есть:
uses
System.SysUtils,
System.IOUtils,
System.Math,
System.Messaging,
FMX.Platform,
FMX.Platform.Android,
Androidapi.Helpers,
Androidapi.JNI.Os,
Androidapi.JNI.GraphicsContentViewText,
Androidapi.JNI.JavaTypes,
Androidapi.JNI.Webkit,
Androidapi.JNI.Net,
Androidapi.JNIBridge,
Androidapi.JNI.App,
Androidapi.JNI.Support,
Androidapi.JNI.Provider,
Androidapi.JNI.Widget,
Androidapi.JNI.Embarcadero;
procedure ShowToast(const Text: string);
begin
TJToast.JavaClass.makeText(SharedActivityContext,
StrToJCharSequence(Text),TJToast.JavaClass.LENGTH_LONG).show;
end;