Flutter正弦波生成与展示插件flutter_sinusoidals_v2的使用
Flutter正弦波生成与展示插件flutter_sinusoidals_v2的使用
flutter_sinusoidals_v2 是一个用于可视化正弦波的 Flutter 包。它支持多种内置波形，并且可以创建自定义波形。
功能
- 创建正弦波。
- 创建正弦波堆叠。
- 将多个正弦波组合在一起。
- 理论上，你可以将该包应用于任何小部件。例如，在底部带有波形的AppBar。
开始使用
在你的 Flutter 项目的 pubspec.yaml 文件中添加以下依赖：
dependencies:
...
flutter_sinusoidals_v2:
在你的代码中添加以下导入：
import 'package:flutter_sinusoidals_v2/flutter_sinusoidals_v2.dart';
内置波形
正弦波 (Sinusoidal)
帮助你可视化正弦波的小部件。
示例代码：
Sinusoidal(
model: const SinusoidalModel(
formular: WaveFormular.standing,
amplitude: 25,
waves: 2.5,
frequency: 1.5,
),
child: Container(
height: 100,
color: Colors.blue,
),
),
多个正弦波 (Sinusoidals)
帮助你可视化多个正弦波堆叠的小部件。
示例代码：
Sinusoidals(
itemCount: 3,
builder: (context, index) {
return SinusoidalItem(
model: SinusoidalModel(
formular: WaveFormular.travelling,
amplitude: _amplitude,
waves: _waves,
translate: 5.0 * (index + 1),
center: 5.0 * (index + 1),
),
child: Container(
height: _height,
color: _colors[index],
),
);
},
);
组合波 (CombinedWave)
帮助你可视化由多个正弦波组合而成的波形。
示例代码：
CombinedWave(
reverse: true,
models: const [
SinusoidalModel(
amplitude: 25,
waves: 20,
translate: 2.5,
frequency: 0.5,
),
SinusoidalModel(
amplitude: 25,
waves: 15,
translate: 7.5,
frequency: 1.5,
),
],
child: Container(
height: 200,
color: Colors.blue,
),
),
岩浆波 (MagmaWave)
模拟岩浆运动的预定义波形。
示例代码：
MagmaWave(
reverse: true,
child: Container(
height: 200,
color: Colors.red,
),
),
完整示例代码
import 'package:flutter/material.dart';
import 'package:flutter_sinusoidals_v2/flutter_sinusoidals_v2.dart';
void main() => runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return const MaterialApp(
title: 'Material App',
home: Scaffold(
body: _MagmaWaveDemo(),
),
);
}
}
const _colors = [
Colors.brown,
Colors.amber,
Colors.teal,
Colors.cyan,
Colors.blue,
Colors.grey,
];
class _SinusoidalsDemo extends StatelessWidget {
const _SinusoidalsDemo({Key? key}) : super(key: key);
static const _amplitude = 45.0;
static const _waves = 3.0;
static const _height = 200.0;
[@override](/user/override)
Widget build(BuildContext context) {
return Column(
children: [
const SizedBox(height: 32),
Sinusoidals(
reverse: true,
itemCount: 3,
builder: (context, index) {
return SinusoidalItem(
model: SinusoidalModel(
formular: WaveFormular.standing,
amplitude: _amplitude,
waves: _waves,
translate: 5.0 * (index + 1),
center: 5.0 * (index + 1),
frequency: 0.5,
),
child: Container(
height: _height,
color: _colors[index],
),
);
},
),
const Spacer(),
Sinusoidals(
itemCount: 3,
builder: (context, index) {
return SinusoidalItem(
model: SinusoidalModel(
formular: WaveFormular.travelling,
amplitude: _amplitude,
waves: _waves,
translate: 5.0 * (index + 1),
center: 5.0 * (index + 1),
frequency: 0.5,
),
child: Container(
height: _height,
color: _colors[index],
),
);
},
),
],
);
}
}
class _SinusoidalDemo extends StatelessWidget {
const _SinusoidalDemo({Key? key}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
const SizedBox(height: 32),
Sinusoidal(
reverse: true,
model: const SinusoidalModel(
amplitude: 15,
waves: 5,
frequency: -0.5,
),
child: Container(
height: 100,
color: Colors.blue,
),
),
const SizedBox(height: 50),
Sinusoidal(
model: const SinusoidalModel(
amplitude: 15,
waves: 5,
),
child: Container(
height: 100,
color: Colors.blue,
),
),
const SizedBox(height: 50),
Sinusoidal(
model: const SinusoidalModel(
formular: WaveFormular.standing,
translate: 5.0,
amplitude: 25,
waves: 2,
frequency: 0.5,
),
child: Container(
height: 100,
color: Colors.blue,
),
),
const SizedBox(height: 50),
Sinusoidal(
model: const SinusoidalModel(
formular: WaveFormular.travelling,
amplitude: 25,
waves: 2.5,
frequency: 0.5,
),
child: Container(
height: 100,
color: Colors.blue,
),
),
],
);
}
}
class _CombinedWaveDemo extends StatelessWidget {
const _CombinedWaveDemo({Key? key}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
const SizedBox(height: 32),
CombinedWave(
reverse: true,
models: const [
SinusoidalModel(
amplitude: 25,
waves: 20,
translate: 2.5,
frequency: 0.5,
),
SinusoidalModel(
amplitude: 25,
waves: 15,
translate: 7.5,
frequency: 1.5,
),
],
child: Container(
height: 200,
color: Colors.blue,
),
),
const Spacer(),
CombinedWave(
models: const [
SinusoidalModel(
amplitude: 25,
waves: 20,
translate: 2.5,
frequency: 0.5,
),
SinusoidalModel(
amplitude: 25,
waves: 15,
translate: 7.5,
frequency: 1.5,
),
],
child: Container(
height: 200,
color: Colors.blue,
),
),
],
);
}
}
class _MagmaWaveDemo extends StatelessWidget {
const _MagmaWaveDemo({Key? key}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return Column(
children: [
const SizedBox(height: 32),
MagmaWave(
reverse: true,
child: Container(
height: 200,
color: Colors.red,
),
),
const Spacer(),
MagmaWave(
child: Container(
height: 200,
color: Colors.red,
),
),
],
);
}
}
更多关于Flutter正弦波生成与展示插件flutter_sinusoidals_v2的使用的实战教程也可以访问 https://www.itying.com/category-92-b0.html
1 回复
更多关于Flutter正弦波生成与展示插件flutter_sinusoidals_v2的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
当然，以下是如何在Flutter项目中使用flutter_sinusoidals_v2插件来生成并展示正弦波的示例代码。这个插件假设它提供了绘制正弦波的基本功能。请注意，实际插件的API可能会有所不同，因此下面的代码是基于假设的API编写的。如果实际插件的API有所不同，请查阅该插件的官方文档进行调整。
首先，确保在你的pubspec.yaml文件中添加了对flutter_sinusoidals_v2插件的依赖：
dependencies:
flutter:
sdk: flutter
flutter_sinusoidals_v2: ^latest_version # 替换为实际版本号
然后，运行flutter pub get来安装依赖。
接下来，在你的Flutter项目中创建一个展示正弦波的页面。以下是一个简单的示例：
import 'package:flutter/material.dart';
import 'package:flutter_sinusoidals_v2/flutter_sinusoidals_v2.dart'; // 假设插件的导入路径
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Sine Wave Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: SineWaveScreen(),
);
}
}
class SineWaveScreen extends StatefulWidget {
@override
_SineWaveScreenState createState() => _SineWaveScreenState();
}
class _SineWaveScreenState extends State<SineWaveScreen> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Sine Wave Demo'),
),
body: Center(
child: SineWaveWidget(
amplitude: 100.0, // 振幅
frequency: 1.0, // 频率
phase: 0.0, // 相位
offset: Offset(0, 0), // 偏移量
color: Colors.blue,
strokeWidth: 2.0,
height: 300.0,
width: MediaQuery.of(context).size.width,
),
),
);
}
}
// 假设的SineWaveWidget，实际插件可能有不同的API
class SineWaveWidget extends StatelessWidget {
final double amplitude;
final double frequency;
final double phase;
final Offset offset;
final Color color;
final double strokeWidth;
final double height;
final double width;
SineWaveWidget({
required this.amplitude,
required this.frequency,
required this.phase,
required this.offset,
required this.color,
required this.strokeWidth,
required this.height,
required this.width,
});
@override
Widget build(BuildContext context) {
// 注意：这里假设flutter_sinusoidals_v2有一个SineWaveCanvas可以绘制正弦波
// 如果实际插件不同，请查阅其文档进行调整
return CustomPaint(
size: Size(width, height),
painter: SineWavePainter(
amplitude: amplitude,
frequency: frequency,
phase: phase,
offset: offset,
color: color,
strokeWidth: strokeWidth,
),
);
}
}
// 自定义Painter绘制正弦波
class SineWavePainter extends CustomPainter {
final double amplitude;
final double frequency;
final double phase;
final Offset offset;
final Color color;
final double strokeWidth;
SineWavePainter({
required this.amplitude,
required this.frequency,
required this.phase,
required this.offset,
required this.color,
required this.strokeWidth,
});
@override
void paint(Canvas canvas, Size size) {
final Paint paint = Paint()
..color = color
..style = PaintingStyle.stroke
..strokeWidth = strokeWidth;
final Path path = Path();
final double startX = offset.dx;
final double startY = size.height / 2 + amplitude * Math.sin(phase);
path.moveTo(startX, startY);
for (double x = startX; x <= size.width + offset.dx; x += 1.0) {
final double y = size.height / 2 + amplitude * Math.sin(frequency * x + phase);
path.lineTo(x, y);
}
canvas.drawPath(path, paint);
}
@override
bool shouldRepaint(covariant CustomPainter oldDelegate) {
// 如果参数改变，返回true
if (oldDelegate is SineWavePainter) {
final SineWavePainter oldPainter = oldDelegate as SineWavePainter;
return oldPainter.amplitude != amplitude ||
oldPainter.frequency != frequency ||
oldPainter.phase != phase ||
oldPainter.offset != offset ||
oldPainter.color != color ||
oldPainter.strokeWidth != strokeWidth;
}
return true;
}
}
请注意，上述代码中的SineWaveWidget和SineWavePainter是假设性的，实际使用时，你应该根据flutter_sinusoidals_v2插件的实际API进行调整。如果插件提供了现成的绘制正弦波的组件，你应该直接使用该组件而不是自己实现CustomPainter。
此外，如果插件的API与假设的不同，请查阅该插件的官方文档或示例代码，了解如何正确使用该插件来绘制正弦波。
