Flutter占位符展示插件mr_skeleton的使用
在Flutter开发中，占位符展示插件mr_skeleton可以帮助开发者快速实现加载状态的UI效果。通过使用该插件，可以轻松地为应用添加骨架屏（Skeleton Screen）效果，从而提升用户体验。
使用步骤
以下是一个完整的示例，展示如何使用mr_skeleton插件来创建一个带有动态调整宽度的侧边栏和顶部栏的骨架屏。
完整示例代码
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:mr_skeleton/mr_skeleton.dart';
import 'package:resonant_ui/resonant_ui.dart';
import 'package:syncfusion_flutter_sliders/sliders.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 MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: const SkeletonPage(),
);
}
}
class SkeletonPage extends StatelessWidget {
final bool isDebug = false;
const SkeletonPage({Key? key}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
Get.put(SkeletonDemoStateController(isDebug: isDebug));
return Obx(() {
final controller = SkeletonDemoStateController.to;
final isLeftExpanded = controller.isLeftSideMenuExpanded();
final isRightExpanded = controller.isRightSideMenuExpanded();
final expandedLeftWidth = controller.expandedLeftWidth();
final collapsedLeftWidth = controller.collapsedLeftWidth();
final expandedRightWidth = controller.expandedRightWidth();
final isDesktop = controller.isDesktop();
return MRSkeleton(
isLeftExpanded: isLeftExpanded,
isRightExpanded: isRightExpanded,
expandedLeftWidth: expandedLeftWidth,
collapsedLeftWidth: collapsedLeftWidth,
expandedRightWidth: expandedRightWidth,
onDesktopBreakpointChanged: (isDesktop) {
controller.isDesktop(isDesktop);
},
left: _LeftWidget(
isCollapsed: !isLeftExpanded,
),
top: const TopBar(
children: [
_CircularLetter(
letter: '1',
color: Colors.purple,
),
_CircularLetter(
letter: '2',
color: Colors.orange,
),
Spacer(),
_CircularLetter(
letter: '3',
color: Colors.yellow,
),
],
),
right: const _RightWidget(),
body: _SkeletonDemoInteractionBox(
isDesktop: isDesktop,
),
mobileBuilder: (child) {
return Scaffold(
body: SafeArea(
child: Padding(
padding: const EdgeInsets.all(16),
child: child,
),
),
appBar: AppBar(
elevation: 0,
automaticallyImplyLeading: false,
title: const Text(
'App Bar',
style: TextStyle(color: Colors.black),
),
leading: const _CircularLetter(
letter: 'W',
color: Colors.pink,
),
backgroundColor: Colors.transparent,
actions: const [
_CircularLetter(
letter: '1',
color: Colors.purple,
padding: EdgeInsets.all(8),
),
_CircularLetter(
letter: '2',
color: Colors.orange,
padding: EdgeInsets.all(8),
),
],
),
bottomNavigationBar: BottomNavigationBar(
items: const [
BottomNavigationBarItem(
icon: Icon(Icons.call),
label: 'Calls',
),
BottomNavigationBarItem(
icon: Icon(Icons.camera),
label: 'Camera',
),
BottomNavigationBarItem(
icon: Icon(Icons.chat),
label: 'Chats',
),
],
),
);
},
);
});
}
}
class _SkeletonDemoInteractionBox extends StatelessWidget {
final bool isDesktop;
const _SkeletonDemoInteractionBox({Key? key, required this.isDesktop})
: super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
var children = !isDesktop
? [
const Padding(
padding: EdgeInsets.all(16),
child: Text(
'You are on a non-desktop version, expand your screen size or change to a web browser'),
),
]
: [
Obx(() {
return SwitchListTile(
title: const Text('Left expanded'),
value: SkeletonDemoStateController.to.isLeftSideMenuExpanded(),
onChanged: (newValue) {
SkeletonDemoStateController.to
.isLeftSideMenuExpanded(newValue);
},
);
}),
const Divider(),
Obx(() {
return SwitchListTile(
title: const Text('Right expanded'),
value: SkeletonDemoStateController.to.isRightSideMenuExpanded(),
onChanged: (newValue) {
SkeletonDemoStateController.to
.isRightSideMenuExpanded(newValue);
},
);
}),
const Divider(),
Obx(() {
return Column(
children: [
SwitchListTile(
title: const Text('Collapsed Left Width'),
value: SkeletonDemoStateController.to
.enableCollapsedLeftWidthEdition(),
onChanged: (newValue) {
SkeletonDemoStateController.to
.enableCollapsedLeftWidthEdition(newValue);
},
),
Padding(
padding: const EdgeInsets.all(16),
child: SfSlider(
value: SkeletonDemoStateController.to.collapsedLeftWidth(),
min: 60,
max: 300,
interval: 40,
showTicks: true,
showLabels: true,
enableTooltip: true,
onChanged: SkeletonDemoStateController.to
.enableCollapsedLeftWidthEdition()
? (newValue) {
SkeletonDemoStateController.to
.collapsedLeftWidth(newValue);
}
: null,
),
)
],
);
}),
const Divider(),
Obx(() {
return Column(
children: [
SwitchListTile(
title: const Text('Expanded Left Width'),
value: SkeletonDemoStateController.to
.enableExpandedLeftWidthEdition(),
onChanged: (newValue) {
SkeletonDemoStateController.to
.enableExpandedLeftWidthEdition(newValue);
},
),
Padding(
padding: const EdgeInsets.all(16),
child: SfSlider(
value: SkeletonDemoStateController.to.expandedLeftWidth(),
min: 60,
max: 300,
interval: 40,
showTicks: true,
showLabels: true,
enableTooltip: true,
onChanged: SkeletonDemoStateController.to
.enableExpandedLeftWidthEdition()
? (newValue) {
SkeletonDemoStateController.to
.expandedLeftWidth(newValue);
}
: null,
),
)
],
);
}),
const Divider(),
Obx(() {
return Column(
children: [
SwitchListTile(
title: const Text('Expanded Right Width'),
value: SkeletonDemoStateController.to
.enableExpandedRightWidthEdition(),
onChanged: (newValue) {
SkeletonDemoStateController.to
.enableExpandedRightWidthEdition(newValue);
},
),
Padding(
padding: const EdgeInsets.all(16),
child: SfSlider(
value:
SkeletonDemoStateController.to.expandedRightWidth(),
min: 60,
max: 460,
interval: 40,
showTicks: true,
showLabels: true,
enableTooltip: true,
onChanged: SkeletonDemoStateController.to
.enableExpandedRightWidthEdition()
? (newValue) {
SkeletonDemoStateController.to
.expandedRightWidth(newValue);
}
: null,
),
)
],
);
}),
];
return Padding(
padding: const EdgeInsets.all(16),
child: SizedBox(
width: double.infinity,
height: double.infinity,
child: Center(
child: ConstrainedRoundedCard(
title: 'Skeleton demo',
children: children,
),
),
),
);
}
}
class TopBar extends StatelessWidget {
final List<Widget> children;
const TopBar({Key? key, required this.children}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return ColorDebuggable(
color: Colors.amber.shade300,
child: Container(
height: 60,
decoration: BoxDecoration(
border: Border(
bottom: BorderSide(
color: Colors.grey.shade300,
width: 0.5,
),
),
),
child: Row(
mainAxisAlignment: MainAxisAlignment.end,
children: children,
),
),
);
}
}
class _LeftWidget extends StatelessWidget {
final bool isCollapsed;
const _LeftWidget({
Key? key,
this.isCollapsed = false,
}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return ColorDebuggable.amber(
child: Container(
height: double.infinity,
decoration: BoxDecoration(
border: Border(
right: BorderSide(
color: Colors.grey.shade300,
width: 0.5,
),
),
),
child: Column(
crossAxisAlignment: isCollapsed
? CrossAxisAlignment.center
: CrossAxisAlignment.start,
children: [
Container(
width: double.infinity,
height: 60,
decoration: BoxDecoration(
border: Border(
bottom: BorderSide(
color: Colors.grey.shade300,
width: 0.5,
),
),
),
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
const _CircularLetter(
letter: 'L',
color: Colors.cyanAccent,
),
if (!isCollapsed) const Spacer(),
],
),
),
const _CircularLetter(
letter: 'A',
color: Colors.red,
),
const _CircularLetter(
letter: 'B',
color: Colors.green,
),
const Spacer(),
const _CircularLetter(
letter: 'C',
color: Colors.blue,
),
],
),
),
);
}
}
class _RightWidget extends StatelessWidget {
const _RightWidget({Key? key}) : super(key: key);
[@override](/user/override)
Widget build(BuildContext context) {
return ColorDebuggable.amber(
child: Container(
height: double.infinity,
decoration: BoxDecoration(
border: Border(
left: BorderSide(
color: Colors.grey.shade300,
width: 0.5,
),
),
),
child: Column(
children: [
Container(
width: double.infinity,
height: 60,
decoration: BoxDecoration(
border: Border(
bottom: BorderSide(
color: Colors.grey.shade300,
width: 0.5,
),
),
),
child: Row(
children: const [
_CircularLetter(
letter: 'W',
color: Colors.pink,
),
Spacer(),
],
),
),
const Expanded(
child: Center(
child: Text('Right'),
),
),
],
),
),
);
}
}
class _CircularLetter extends StatelessWidget {
const _CircularLetter({
Key? key,
this.onTap,
this.padding,
required this.letter,
this.color = Colors.transparent,
}) : super(key: key);
final Function()? onTap;
final EdgeInsets? padding;
final String letter;
final Color? color;
[@override](/user/override)
Widget build(BuildContext context) {
return ColorDebuggable.blue(
child: Container(
padding: padding ?? const EdgeInsets.all(6),
child: ClipOval(
child: Material(
color: color, // Button color
child: InkWell(
splashColor: Colors.blueGrey.shade100, // Splash color
onTap: onTap,
child: SizedBox(
width: 40,
height: 40,
child: Center(
child: Text(letter),
),
),
),
),
),
),
);
}
}
class SkeletonDemoStateController extends GetxController {
final bool isDebug;
SkeletonDemoStateController({
this.isDebug = false,
});
var isLayoutDebug = false.obs;
var enableCollapsedLeftWidthEdition = false.obs;
var enableExpandedLeftWidthEdition = false.obs;
var enableExpandedRightWidthEdition = false.obs;
static SkeletonDemoStateController get to => Get.find();
[@override](/user/override)
void onReady() {
isLayoutDebug(isDebug);
super.onReady();
}
var currentIndex = 0.obs;
var isLeftSideMenuExpanded = true.obs;
var isRightSideMenuExpanded = true.obs;
var isDesktop = true.obs;
var collapsedLeftWidth = 60.0.obs;
var expandedLeftWidth = 180.0.obs;
var expandedRightWidth = 300.0.obs;
Rx<Color> color = Colors.black.obs;
String get currentRoute => Get.currentRoute;
void toggleLeftSide() {
isLeftSideMenuExpanded.toggle();
}
void toggleRightSide() {
isRightSideMenuExpanded.toggle();
}
void reset(Color? newColor) {
color(newColor ?? Colors.black);
isLeftSideMenuExpanded(true);
isRightSideMenuExpanded(true);
}
void changePage(int? index) {
currentIndex.value = index ?? 0;
}
}
1 回复
更多关于Flutter占位符展示插件mr_skeleton的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html
mr_skeleton 是一个用于在 Flutter 应用中展示占位符（Skeleton）效果的插件。它可以帮助你在数据加载时展示一个骨架屏，提升用户体验。以下是如何使用 mr_skeleton 插件的详细步骤：
1. 添加依赖
首先，你需要在 pubspec.yaml 文件中添加 mr_skeleton 插件的依赖：
dependencies:
flutter:
sdk: flutter
mr_skeleton: ^1.0.0 # 请使用最新版本然后运行 flutter pub get 来安装依赖。
2. 基本使用
mr_skeleton 提供了 Skeleton 和 SkeletonList 两个主要的组件，分别用于单个占位符和列表占位符。
单个占位符 (Skeleton)
你可以使用 Skeleton 组件来创建一个简单的占位符：
import 'package:flutter/material.dart';
import 'package:mr_skeleton/mr_skeleton.dart';
class MyHomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Skeleton Example'),
),
body: Center(
child: Skeleton(
width: 200,
height: 100,
borderRadius: BorderRadius.circular(8),
),
),
);
}
}列表占位符 (SkeletonList)
如果你需要展示一个列表的占位符，可以使用 SkeletonList 组件：
import 'package:flutter/material.dart';
import 'package:mr_skeleton/mr_skeleton.dart';
class MyHomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Skeleton List Example'),
),
body: SkeletonList(
length: 5, // 列表项的数量
builder: (context, index) => Skeleton(
width: double.infinity,
height: 100,
borderRadius: BorderRadius.circular(8),
margin: EdgeInsets.symmetric(vertical: 8),
),
),
);
}
}3. 自定义占位符
你可以通过 Skeleton 组件的参数来自定义占位符的外观，例如颜色、圆角、边距等。
Skeleton(
width: 200,
height: 100,
borderRadius: BorderRadius.circular(8),
color: Colors.grey[300], // 占位符颜色
margin: EdgeInsets.all(8), // 外边距
padding: EdgeInsets.all(8), // 内边距
)4. 控制占位符的显示与隐藏
通常，你会在数据加载时显示占位符，数据加载完成后隐藏占位符。你可以通过 Visibility 组件或条件渲染来控制占位符的显示与隐藏。
bool isLoading = true; // 假设这是一个加载状态
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Skeleton Example'),
),
body: Center(
child: isLoading
? Skeleton(
width: 200,
height: 100,
borderRadius: BorderRadius.circular(8),
)
: Text('Data Loaded!'),
),
);
}5. 动画效果
mr_skeleton 默认会为占位符添加一个渐变动画效果，你可以通过 animationDuration 和 animationCurve 参数来自定义动画的持续时间和曲线。
Skeleton(
width: 200,
height: 100,
borderRadius: BorderRadius.circular(8),
animationDuration: Duration(seconds: 2), // 动画持续时间
animationCurve: Curves.easeInOut, // 动画曲线
)