Flutter How to show splash screen only while loading flutter data

Question

While the app's splash screen is displayed, it needs to download files from the FTP server and process data. Implemented splash screen for flutter

class Home extends StatelessWidget {
  const Home({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {

    return FutureBuilder(
      future: Future.delayed(Duration(seconds: 3)),
      builder: (BuildContext context, AsyncSnapshot snapshot){
        if(snapshot.connectionState == ConnectionState.waiting)
          return SplashUI();    ///Splash Screen
        else
          return MainUI();       ///Main Screen
      },
    );
  }
}

Now, with a delay of 3 seconds, the startup screen is displayed for 3 seconds, during which time the file is downloaded from FTP and data is processed. I want to keep the splash screen until the completion of data processing rather than the specified time.

Splash Screen

Widget _splashUI(Size size){
    return SafeArea(
      child: Center(
        child: Container(
          width: size.width * 0.5,
          height: size.height * 0.1,
          child: Image(
            fit: BoxFit.fill,
            image: AssetImage('assets/images/elf_logo.png'),
          ),
        ),
      ),
    );
  }

 Widget build(BuildContext context) {

 getFtpFile();
 dataProgress();

 return Platform.isAndroid ?
    MaterialApp(
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: _splashUI(_size),
      ),
    ) :
    CupertinoApp(
      debugShowCheckedModeBanner: false,
      home: CupertinoPageScaffold(
        child: _splashUI(_size),
      ),
    );
 }

I want to know how to keep SplashScreen while processing data rather than handling SplashScreen with delayed. thank you.

Answer 1

The package flutter_native_splash does exactly what you are asking for. Make a call to FlutterNativeSplash.preserve() before your runApp() to keep the splash on screen, then FlutterNativeSplash.remove(); when your download completes:

import 'package:flutter_native_splash/flutter_native_splash.dart';

void main() {
  WidgetsBinding widgetsBinding = WidgetsFlutterBinding.ensureInitialized();
  FlutterNativeSplash.preserve(widgetsBinding: widgetsBinding);
  runApp(const MyApp());
}

// when your download is completed, remove the splash screen:
    FlutterNativeSplash.remove();

Full disclosure: I maintain this package.