Flutter拖拽视图插件flutterx_drop_view的使用

发布于 1周前 作者 itying888 来自 Flutter

Flutter拖拽视图插件flutterx_drop_view的使用

flutterx_drop_view 是一个可以让你将文件拖放到其中的部件,并且可以从系统文件浏览器中选择文件的部件。

导入

导入库的方式如下:

import 'package:flutterx_drop_view/flutterx_drop_view.dart';

使用

以下是一个完整的示例,展示了如何在Flutter应用中使用 flutterx_drop_view 插件。

示例代码

import 'package:cross_file/cross_file.dart';
import 'package:flutter/material.dart';
import 'package:flutterx_drop_view/flutterx_drop_view.dart';
import 'package:flutterx_forms/flutterx_forms.dart';
import 'package:flutterx_live_data/flutterx_live_data.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  [@override](/user/override)
  Widget build(BuildContext context) => MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'Flutterx DropView Demo',
      theme: ThemeData(primarySwatch: Colors.deepOrange).applyAppTheme(),
      home: const DropViewExample());
}

extension _ThemeDataExt on ThemeData {
  ThemeData applyAppTheme() => copyWith(
      outlinedButtonTheme: OutlinedButtonThemeData(
          style: OutlinedButton.styleFrom(backgroundColor: Colors.blueAccent, side: const BorderSide())),
      inputDecorationTheme: InputDecorationTheme(
          labelStyle: const TextStyle(),
          floatingLabelStyle: TextStyle(color: colorScheme.primary),
          border: const OutlineInputBorder(),
          focusedBorder: OutlineInputBorder(borderSide: BorderSide(color: colorScheme.primary, width: 2))));
}

class DropViewExample extends StatefulWidget {
  const DropViewExample({Key? key}) : super(key: key);

  [@override](/user/override)
  State<DropViewExample> createState() => _DropViewExampleState();
}

class _DropViewExampleState extends State<DropViewExample> {
  final MutableLiveData<XFile?> _file = MutableLiveData();
  final GlobalKey<FormState> _form = GlobalKey();

  [@override](/user/override)
  Widget build(BuildContext context) => Scaffold(
      appBar: AppBar(title: const Text('DropView example')),
      body: Form(
        key: _form,
        child: Column(mainAxisSize: MainAxisSize.min, children: [
          Container(width: kMinInteractiveDimension * 8, padding: const EdgeInsets.all(8), child: TextFormField()),
          Container(
              width: kMinInteractiveDimension * 8,
              padding: const EdgeInsets.all(8),
              child: FileUploadFormField(
                  validator: [
                    nonNull(message: 'No file selected'),
                    fileMimeType(const {'application/pdf'}),
                  ].validator,
                  autovalidateMode: AutovalidateMode.onUserInteraction,
                  onMimeTypeNotMatch: (error) =>
                      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(error.toString()))),
                  value: _file)),
          ElevatedButton(onPressed: () => _form.currentState?.validate(), child: const Text('VALIDATE')),
        ]),
      ));
}

更多关于Flutter拖拽视图插件flutterx_drop_view的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html

1 回复

更多关于Flutter拖拽视图插件flutterx_drop_view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,以下是一个关于如何在Flutter项目中使用flutterx_drop_view插件来实现拖拽视图功能的示例代码。flutterx_drop_view是一个第三方库,允许你创建可拖拽和放置的视图组件。请注意,由于我无法实时验证第三方库的版本和可用性,下面的代码基于假设该库存在并且其API与我描述的一致。

首先,确保你的pubspec.yaml文件中已经添加了flutterx_drop_view依赖:

dependencies:
  flutter:
    sdk: flutter
  flutterx_drop_view: ^最新版本号  # 请替换为实际的最新版本号

然后运行flutter pub get来安装依赖。

接下来,在你的Flutter应用中实现拖拽视图功能。以下是一个简单的示例:

import 'package:flutter/material.dart';
import 'package:flutterx_drop_view/flutterx_drop_view.dart';  // 假设库提供了这样的导入路径

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Drag and Drop Example',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final List<String> items = ['Item 1', 'Item 2', 'Item 3'];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Flutter Drag and Drop Example'),
      ),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            // 可拖拽的列表项
            for (var item in items)
              DraggableWidget(
                key: ValueKey(item),
                data: item,
                child: Container(
                  padding: EdgeInsets.all(16.0),
                  margin: EdgeInsets.symmetric(vertical: 8.0),
                  decoration: BoxDecoration(
                    color: Colors.grey[200],
                    borderRadius: BorderRadius.circular(8.0),
                  ),
                  child: Text(item),
                ),
              ),
            // 放置区域
            SizedBox(height: 20.0),
            DropTargetWidget(),
          ],
        ),
      ),
    );
  }
}

class DraggableWidget extends StatelessWidget {
  final String data;
  final Widget child;

  const DraggableWidget({Key key, @required this.data, @required this.child})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Draggable<String>(
      data: data,
      child: child,
      feedback: Material(
        color: Colors.transparent,
        child: child,
      ),
      childWhenDragging: Container(
        decoration: BoxDecoration(
          color: Colors.grey[100],
          borderRadius: BorderRadius.circular(8.0),
        ),
        child: Center(child: CircularProgressIndicator()),
      ),
    );
  }
}

class DropTargetWidget extends StatefulWidget {
  @override
  _DropTargetWidgetState createState() => _DropTargetWidgetState();
}

class _DropTargetWidgetState extends State<DropTargetWidget> {
  String droppedItem;

  @override
  Widget build(BuildContext context) {
    return DropTarget<String>(
      onAccept: (data) {
        setState(() {
          droppedItem = data;
        });
      },
      onWillAccept: (data) {
        return true; // 允许接受所有拖拽的数据
      },
      builder: (context, candidateData, rejectedData) {
        return Container(
          padding: EdgeInsets.all(32.0),
          decoration: BoxDecoration(
            color: Colors.blue[100],
            borderRadius: BorderRadius.circular(8.0),
          ),
          child: droppedItem == null
              ? Text('Drop here')
              : Text('Dropped: $droppedItem'),
        );
      },
    );
  }
}

在这个示例中:

  1. DraggableWidget是一个封装了Draggable组件的自定义小部件,它允许你拖拽列表项。
  2. DropTargetWidget是一个封装了DropTarget组件的自定义小部件,它定义了放置区域,当拖拽项被放置在这里时,会显示被放置的项。
  3. MyHomePage构建了一个包含可拖拽列表项和放置区域的界面。

请注意,flutterx_drop_view库的具体API和实现可能有所不同,因此上述代码是一个基于假设的示例。如果flutterx_drop_view库不存在或API有所变化,你可能需要查阅该库的官方文档或源代码来调整代码。

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