Android实例-退出程序(XE8+小米2)

 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.Controls.Presentation, FMX.StdCtrls;

 type
   TForm1 = class(TForm)
     Button1: TButton;
     Button2: TButton;
     Button3: TButton;
     Label1: TLabel;
     Button4: TButton;
     Button5: TButton;
     Button6: TButton;
     procedure Button1Click(Sender: TObject);
     procedure Button2Click(Sender: TObject);
     procedure Button3Click(Sender: TObject);
     procedure FormKeyUp(Sender: TObject; var Key: Word; var KeyChar: Char;
       Shift: TShiftState);
     procedure Button4Click(Sender: TObject);
     procedure Button6Click(Sender: TObject);
     procedure Button5Click(Sender: TObject);
   private
     { Private declarations }
   public
     { Public declarations }
   end;

 var
   Form1: TForm1;

 implementation
 uses
 FMX.Platform.Android,
 FMX.Helpers.Android,
 Androidapi.JNI.Net,
 Androidapi.JNI.GraphicsContentViewText,
 Androidapi.JNI.JavaTypes,
 Androidapi.Helpers,
 system.IOUtils;

 {$R *.fmx}
 {$R *.NmXhdpiPh.fmx ANDROID}
 {$R *.LgXhdpiPh.fmx ANDROID}
 {$R *.Macintosh.fmx MACOS}
 {$R *.XLgXhdpiTb.fmx ANDROID}
 {$R *.LgXhdpiTb.fmx ANDROID}
 {$R *.GGlass.fmx ANDROID}

 procedure TForm1.Button1Click(Sender: TObject);
 begin
   Label1.Text := '按返回键将会出现一个对话框！';
 end;

 procedure TForm1.Button2Click(Sender: TObject);
 begin
   MainActivity.finish; { 退出程序 }
 end;

 procedure TForm1.Button3Click(Sender: TObject);
 begin
   {$IFDEF ANDROID}
     Application.MainForm.DisposeOf; { 退出程序 }
     halt();
   {$ENDIF}
 end;

 procedure TForm1.Button4Click(Sender: TObject);
 var
   Intent: JIntent;
 begin
   Intent := TJIntent.JavaClass.init(TJIntent.JavaClass.ACTION_MAIN);
   Intent.addCategory(TJIntent.JavaClass.CATEGORY_HOME);
   Intent.setFlags(TJIntent.JavaClass.FLAG_ACTIVITY_NEW_TASK);
   SharedActivityContext.startActivity(Intent);
 end;

 procedure TForm1.Button5Click(Sender: TObject);
 begin
   Application.Terminate;
 end;

 procedure TForm1.Button6Click(Sender: TObject);
 begin
   Close;
 end;
 //此代码报错，不可用，原因不明。
 procedure TForm1.FormKeyUp(Sender: TObject; var Key: Word; var KeyChar: Char;
   Shift: TShiftState);
 begin
   if Key = vkHardwareBack then//如果按下物理返回键
   begin
     Label1.Text := '';
     if MessageDlg('确认退出吗？', TMsgDlgType.mtConfirmation,
     [TMsgDlgBtn.mbOK, TMsgDlgBtn.mbCancel], -) = mrOK then
       MainActivity.finish; { 退出程序 }
     Key := ;//必须的，不然按否也会退出
     Exit;
   end;
 end;

 end.