覚えています、私は同じ挑戦をしました。
私は自分のウェーブスライダーを作成します:
import 'Dart:math';
import 'package:flutter/material.Dart';
List<int> bars = [];
const barWidth = 5.0;
double screenWidth;
int numberOfBars;
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Home(),
);
}
}
void randomNumberGenerator() {
Random r = Random();
for (var i = 0; i < numberOfBars; i++) {
bars.add(r.nextInt(40) + 10);
}
}
class Home extends StatelessWidget {
@override
Widget build(BuildContext context) {
if (bars.isEmpty) {
screenWidth = MediaQuery.of(context).size.width;
numberOfBars = screenWidth ~/ barWidth;
randomNumberGenerator();
}
return Container(child: WaveSlider());
}
}
class WaveSlider extends StatefulWidget {
@override
State<StatefulWidget> createState() => WaveSliderState();
}
class WaveSliderState extends State<WaveSlider> {
double bar2Position = 180.0;
_onTapDown(TapDownDetails details) {
var x = details.globalPosition.dx;
print("tap down " + x.toString());
setState(() {
bar2Position = x;
});
}
@override
Widget build(BuildContext context) {
int barItem = 0;
return Scaffold(
body: Center(
child: Stack(
alignment: Alignment.centerLeft,
children: <Widget>[
GestureDetector(
onTapDown: (TapDownDetails details) => _onTapDown(details),
onHorizontalDragUpdate: (DragUpdateDetails details) {
setState(() {
bar2Position = details.globalPosition.dx;
});
},
child: Container(
child: Row(
crossAxisAlignment: CrossAxisAlignment.end,
mainAxisAlignment: MainAxisAlignment.start,
children: bars.map((int height) {
Color color = barItem + 1 < bar2Position / barWidth
? Colors.deepPurple
: Colors.blueGrey;
barItem++;
return Container(
color: color,
height: height.toDouble(),
width: 5.0,
);
}).toList(),
),
),
),
],
),
),
);
}
}