在颤振应用程序中添加启动画面的正确方法是什么？

Question

我正在开发一个基于 Flutter 的应用程序，并研究了几种添加启动画面的方法。但我不确定哪一个是最好的实现。

Answer 1

    import 'dart:async';
import 'package:flutter/material.dart';
import 'package:mingup/screen/login_screen.dart';

// This is the Splash Screen
class SplashScreen extends StatefulWidget {
  @override
  _SplashScreenState createState() => _SplashScreenState();
}

class _SplashScreenState extends State<SplashScreen> with SingleTickerProviderStateMixin{

  AnimationController _animationController;
  Animation<double> _animation;

  @override
  void initState() {
    // TODO: implement initState
    super.initState();
    _animationController = new AnimationController(
        vsync: this,
        duration: new Duration(milliseconds: 500)
    );
    _animation = new CurvedAnimation(
      parent: _animationController,
      curve: Curves.easeOut,
    );

    _animation.addListener(()=> this.setState((){}));
    _animationController.forward();

    Timer(Duration(seconds: 10), (){
      Navigator.push(context, MaterialPageRoute(builder: (context) => LoginScreen()));
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Stack(
        fit: StackFit.expand,
        children: <Widget>[
          Container(
            child: Image.asset(
              'images/splashscreenbg.png',
              fit: BoxFit.cover,
            )
          ),
          Column(
            mainAxisAlignment: MainAxisAlignment.start,
            children: <Widget>[
              Expanded(
                flex: 2,
                child: Container(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: <Widget>[
                      FlutterLogo(
                        size: _animation.value * 100.0,
                      ),
                      Padding(padding: EdgeInsets.only(top: 10.0)),
                      Text("MingUp", style: TextStyle(color: Colors.white, fontSize: 24.0, fontWeight: FontWeight.bold),)
                    ],
                  ),
                ),
              ),
            ]
          )
        ],
      ),
    );
  }
}

Answer 2

您可以只添加一个简单的启动屏幕，它可以在 5 秒后导航到下一个屏幕。

import 'package:flutter/material.dart';
import 'dart:async';


class SplashScreen extends StatefulWidget {
  @override
  _SplashScreenState createState() => _SplashScreenState();
}

class _SplashScreenState extends State<SplashScreen> {
  @override
  void initState() {
    super.initState();
    Timer(
        Duration(seconds: 5),
        () => Navigator.pushReplacement(
            context, MaterialPageRoute(builder: (context) => Home())));
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Stack(
        fit: StackFit.expand,
        children: <Widget>[
          Container(
            decoration: BoxDecoration(
              color: Color.fromRGBO(20, 172, 168, 1),
            ),
          ),
          Column(
            mainAxisAlignment: MainAxisAlignment.start,
            children: <Widget>[
              Expanded(
                flex: 2,
                child: Container(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: <Widget>[
                      CircleAvatar(
                          backgroundColor: Colors.white,
                          radius: 60.0,
                          child: new Image.asset(
                            'assets/images/tree.jpg',
                            width: 70,
                            height: 90,
                          )),
                      Padding(
                        padding: EdgeInsets.only(top: 10.0),
                      ),
                      Text(
                        'Your Text here!!',
                        style: TextStyle(
                            color: Colors.white,
                            fontWeight: FontWeight.bold,
                            fontSize: 24.0),
                      )
                    ],
                  ),
                ),
              ),
              Expanded(
                flex: 1,
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: <Widget>[
                    CircularProgressIndicator(),
                    Padding(
                      padding: EdgeInsets.only(top: 20.0),
                    ),
                    Text(
                      'Your Text here!!',
                      softWrap: true,
                      textAlign: TextAlign.center,
                      style: TextStyle(
                          fontWeight: FontWeight.bold,
                          fontSize: 18.0,
                          color: Colors.white),
                    )
                  ],
                ),
              )
            ],
          )
        ],
      ),
    );
  }
}