Flutter色彩处理插件hue_craft的使用
Flutter色彩处理插件hue_craft的使用
hue_craft
是一个用于在 Flutter 中构建自定义颜色选择器的简单包。
示例
下图展示了 hue_craft
插件提供的两个颜色选择器的示例:
包含的部件
hue_craft
包包含以下部件:
- HorizontalHuePicker
- VerticalHuePicker
- HorizontalOpacityPicker
- VerticalOpacityPicker
- SaturationValuePicker
如果你想要为这些部件构建一个自定义的滑块(或选择器),你可以通过实现 CustomPainter
类来完成。这允许你设计一个与你的独特风格匹配的滑块。要实现这一点,你需要:
- 创建一个类,例如
CustomThumb
,它扩展CustomPainter
。 - 实现
paint
和shouldRepaint
方法来定义滑块(或选择器)的外观。
class SquareThumbPainter extends CustomPainter {
final double width;
final double height;
final Color squareColor;
final double borderWidth;
SquareThumbPainter({
required this.width,
required this.height,
required this.squareColor,
this.borderWidth = 2.0,
});
[@override](/user/override)
void paint(Canvas canvas, Size size) {
// 填充画笔
final Paint fillPaint = Paint()..color = squareColor;
// 边框画笔
final Paint borderPaint = Paint()
..color = Colors.white
..style = PaintingStyle.stroke
..strokeWidth = borderWidth;
// 绘制矩形
final Rect rect = Rect.fromCenter(
center: Offset(size.width / 2, size.height / 2),
width: width,
height: height,
);
canvas.drawRect(rect, fillPaint); // 绘制填充矩形
canvas.drawRect(rect, borderPaint); // 绘制边框矩形
}
[@override](/user/override)
bool shouldRepaint(covariant CustomPainter oldDelegate) {
return true;
}
}
现在你可以将其实例传递给任何由该包提供的部件。例如:
HorizontalHuePicker(
customThumbPainter: SquareThumbPainter(...),
...
)
你也可以对其他部件执行相同的操作。
完整示例
以下是完整的示例代码,展示了如何使用 hue_craft
插件。
import 'package:flutter/material.dart';
import 'utils/utils.dart';
import 'dialog/color_picker_one.dart';
import 'dialog/color_picker_two.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
[@override](/user/override)
Widget build(BuildContext context) {
return const MaterialApp(
debugShowCheckedModeBanner: false,
home: MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({super.key});
[@override](/user/override)
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
[@override](/user/override)
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.white,
appBar: AppBar(
title: const Text(
'Example',
style: TextStyle(
color: Colors.white,
fontSize: 20
),
),
backgroundColor: Colors.blue,
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
ElevatedButton(
onPressed: () {
showDialogBox(
context: context,
child: const ColorPickerOneDialog()
);
},
child: const Text(
"Show color picker one"
),
),
ElevatedButton(
onPressed: () {
showDialogBox(
context: context,
child: const ColorPickerTwoDialog()
);
},
child: const Text(
"Show color picker two"
),
)
],
),
),
);
}
}
更多关于Flutter色彩处理插件hue_craft的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
更多关于Flutter色彩处理插件hue_craft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,下面是一个关于如何在Flutter项目中使用hue_craft
插件进行色彩处理的示例代码。hue_craft
插件允许你调整颜色的色调、饱和度、亮度等属性,非常适合需要复杂色彩操作的应用。
首先,确保你已经在pubspec.yaml
文件中添加了hue_craft
依赖:
dependencies:
flutter:
sdk: flutter
hue_craft: ^最新版本号 # 请替换为实际发布的最新版本号
然后运行flutter pub get
来安装依赖。
接下来,我们来看一个完整的示例,展示如何使用hue_craft
插件来调整颜色:
import 'package:flutter/material.dart';
import 'package:hue_craft/hue_craft.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Hue Craft Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: HueCraftDemo(),
);
}
}
class HueCraftDemo extends StatefulWidget {
@override
_HueCraftDemoState createState() => _HueCraftDemoState();
}
class _HueCraftDemoState extends State<HueCraftDemo> {
Color originalColor = Colors.red;
Color adjustedColor = Colors.red;
double hue = 0.0;
double saturation = 1.0;
double lightness = 0.5;
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Hue Craft Demo'),
),
body: Padding(
padding: const EdgeInsets.all(16.0),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
ColorBox(color: originalColor, label: 'Original Color'),
SizedBox(height: 16.0),
ColorBox(color: adjustedColor, label: 'Adjusted Color'),
SizedBox(height: 32.0),
Slider(
value: hue,
min: 0.0,
max: 1.0,
divisions: 10,
label: 'Hue',
onChanged: (newValue) {
setState(() {
hue = newValue;
adjustedColor = HslColor.fromColor(originalColor)
.withHue(hue * 360)
.toColor();
});
},
),
Slider(
value: saturation,
min: 0.0,
max: 1.0,
divisions: 10,
label: 'Saturation',
onChanged: (newValue) {
setState(() {
saturation = newValue;
adjustedColor = HslColor.fromColor(originalColor)
.withSaturation(saturation)
.toColor();
});
},
),
Slider(
value: lightness,
min: 0.0,
max: 1.0,
divisions: 10,
label: 'Lightness',
onChanged: (newValue) {
setState(() {
lightness = newValue;
adjustedColor = HslColor.fromColor(originalColor)
.withLightness(lightness)
.toColor();
});
},
),
],
),
),
);
}
}
class ColorBox extends StatelessWidget {
final Color color;
final String label;
ColorBox({required this.color, required this.label});
@override
Widget build(BuildContext context) {
return Column(
children: <Widget>[
Text(label),
Container(
width: 100,
height: 100,
color: color,
),
],
);
}
}
在这个示例中,我们创建了一个简单的Flutter应用,其中包含了三个滑块用于调整色调(Hue)、饱和度(Saturation)和亮度(Lightness)。我们使用HslColor
类(来自hue_craft
插件)来处理这些调整,并实时更新显示的颜色。
注意,HslColor.fromColor(originalColor)
将RGB颜色转换为HSL颜色,然后我们使用.withHue()
、.withSaturation()
和.withLightness()
方法来调整HSL值,并最终使用.toColor()
方法将HSL颜色转换回RGB颜色以供显示。
你可以根据实际需求进一步扩展这个示例,比如添加更多的颜色操作功能或者优化用户界面。