How do I make my Delphi code compatible with multiple platforms?

Question

I am currently developing a mobile application and my current target platform is Android (since that is the current device I have). However, I want to try and make it compatible with IOS and Windows (testing) as well

My current code for exiting my application uses:

uses FMX.Platform.Android


procedure TfrmMain.btnExitClick(Sender: TObject);
begin
 MainActivity.finish;
end;

How do i make this compatible with IOS or Windows (when testing)? Simply using Close does not work in Android.

Answer 1

You can use conditional compilation to write multi-platform code:

{$IFDEF MSWINDOWS}
    // Do something...
{$ENDIF}
{$IFDEF MACOS}
    // Do something...
{$ENDIF}
{$IFDEF Android}
    // Do something...
{$ENDIF}
{$IFDEF iOS}
    // Don't do anything
{$ENDIF}

Also, take a look at this previous question for more details, especially for closing an application on Android: How to close android app in Delphi-XE5 Firemonkey application?