Вы можете скопировать полный код вставки и вставки ниже
Шаг 1: Вы можете определить bool firstRun = true
Шаг 2: При переходе на другую страницу установите firstRun на false
Шаг 3: В методе _SlideFadeTransitionState build проверьте, не является ли firstRun, и верните widget.child напрямую
return firstRun? FadeTransition(...widget.child) : widget.child
рабочая демонстрация
фрагмент кода
bool firstRun = true;
...
RaisedButton(
child: Text('Open route'),
onPressed: () {
firstRun = false;
Navigator.push(
context,
MaterialPageRoute(builder: (context) => SecondRoute()),
);
},
)
...
@override
Widget build(BuildContext context) {
print('first run ${firstRun}');
return firstRun? FadeTransition(
opacity: _animationFade,
child: SlideTransition(
position: _animationSlide,
child: widget.child,
),
) : widget.child;
}
полный код
import 'dart:async';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
bool firstRun = true;
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
@override
void initState() {
// TODO: implement initState
super.initState();
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: ListView(children: [
Container(
color: Colors.blue,
height: 1000,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
SlideFadeTransition(
delayStart: Duration(milliseconds: 800),
offset: 2,
child: new Text('Test Text 1')),
SlideFadeTransition(
delayStart: Duration(milliseconds: 1200),
offset: 4,
child: new Text('Test Text 2'))
],
),
),
Container(
color: Colors.red,
height: 1000,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
SlideFadeTransition(
delayStart: Duration(milliseconds: 1200),
offset: 2,
child: new Text('Test Text 1')),
SlideFadeTransition(
delayStart: Duration(milliseconds: 2400),
offset: 4,
child: new Text('Test Text 2'))
],
),
),
Container(
color: Colors.orange,
height: 1000,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
SlideFadeTransition(
delayStart: Duration(milliseconds: 1200),
offset: 2,
child: new Text('Test Text 1')),
SlideFadeTransition(
delayStart: Duration(milliseconds: 2400),
offset: 4,
child: new Text('Test Text 2'))
],
),
),
RaisedButton(
child: Text('Open route'),
onPressed: () {
firstRun = false;
Navigator.push(
context,
MaterialPageRoute(builder: (context) => SecondRoute()),
);
},
),
])));
}
}
enum Direction { vertical, horizontal }
class SlideFadeTransition extends StatefulWidget {
///The child on which to apply the given [SlideFadeTransition]
final Widget child;
///The offset by which to slide and [child] into view from [Direction].
///Defaults to 0.2
final double offset;
///The curve used to animate the [child] into view.
///Defaults to [Curves.easeIn]
final Curve curve;
///The direction from which to animate the [child] into view. [Direction.horizontal]
///will make the child slide on x-axis by [offset] and [Direction.vertical] on y-axis.
///Defaults to [Direction.vertical]
final Direction direction;
///The delay with which to animate the [child]. Takes in a [Duration] and
/// defaults to 0.0 seconds
final Duration delayStart;
///The total duration in which the animation completes. Defaults to 800 milliseconds
final Duration animationDuration;
SlideFadeTransition({
@required this.child,
this.offset = 0.2,
this.curve = Curves.easeIn,
this.direction = Direction.vertical,
this.delayStart = const Duration(seconds: 0),
this.animationDuration = const Duration(milliseconds: 800),
});
@override
_SlideFadeTransitionState createState() => _SlideFadeTransitionState();
}
class _SlideFadeTransitionState extends State<SlideFadeTransition>
with SingleTickerProviderStateMixin {
Animation<Offset> _animationSlide;
AnimationController _animationController;
Animation<double> _animationFade;
@override
void initState() {
super.initState();
_animationController = AnimationController(
vsync: this,
duration: widget.animationDuration,
);
//configure the animation controller as per the direction
if (widget.direction == Direction.vertical) {
_animationSlide =
Tween<Offset>(begin: Offset(0, widget.offset), end: Offset(0, 0))
.animate(CurvedAnimation(
curve: widget.curve,
parent: _animationController,
));
} else {
_animationSlide =
Tween<Offset>(begin: Offset(widget.offset, 0), end: Offset(0, 0))
.animate(CurvedAnimation(
curve: widget.curve,
parent: _animationController,
));
}
_animationFade =
Tween<double>(begin: -1.0, end: 1.0).animate(CurvedAnimation(
curve: widget.curve,
parent: _animationController,
));
Timer(widget.delayStart, () {
_animationController.forward();
});
}
@override
Widget build(BuildContext context) {
print('first run ${firstRun}');
return firstRun? FadeTransition(
opacity: _animationFade,
child: SlideTransition(
position: _animationSlide,
child: widget.child,
),
) : widget.child;
}
}
class SecondRoute extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Second Route"),
),
body: Center(
child: RaisedButton(
onPressed: () {
// Navigate back to first route when tapped.
},
child: Text('Go back!'),
),
),
);
}
}