Flutter树形视图插件tree_view_flutter的使用

概述

tree_view_flutter 是一个用于创建可自定义的树形视图的 Flutter 包。通过这个包，您可以轻松地在您的应用中展示具有层次结构的数据。

示例

安装

首先，在您的 pubspec.yaml 文件中添加以下依赖：

dependencies:
  tree_view_flutter: ^1.0.2

然后运行以下命令以获取依赖项：

flutter packages get

示例代码

让我们通过一个具体的例子来展示如何使用 tree_view_flutter 插件。

示例数据结构

假设我们想要展示一个这样的文件系统结构：

Desktop
|-- projects
|   |-- flutter_app
|       |-- README.md
|       |-- pubspec.yaml
|       |-- pubspec.lock
|       |-- .gitignore
|       |-- lib
|           |-- main.dart
|-- test.sh
|-- image.png
|-- image2.png
|-- image3.png

完整示例代码

以下是完整的代码实现：

import 'package:flutter/material.dart';
import 'package:tree_view_flutter/tree_view_flutter.dart';

// 假设这是我们的数据模型
class Document {
  final String name;
  final DateTime dateModified;
  final bool isFile;
  final List<Document>? childData;

  Document({
    required this.name,
    required this.dateModified,
    required this.isFile,
    this.childData,
  });
}

// 目录组件
class DirectoryWidget extends StatelessWidget {
  final String directoryName;
  final DateTime lastModified;

  DirectoryWidget({required this.directoryName, required this.lastModified});

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(directoryName),
        Text("Last modified: ${lastModified.toString()}"),
      ],
    );
  }
}

// 文件组件
class FileWidget extends StatelessWidget {
  final String fileName;
  final DateTime lastModified;

  FileWidget({required this.fileName, required this.lastModified});

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Row(
      children: [
        Icon(Icons.file_copy),
        Text(fileName),
        Text("Last modified: ${lastModified.toString()}"),
      ],
    );
  }
}

void main() => runApp(MainApplication());

class MainApplication extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      home: HomePage(),
    );
  }
}

class HomePage extends StatefulWidget {
  HomePage({Key? key, this.title}) : super(key: key);

  final String? title;

  [@override](/user/override)
  _HomePageState createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  List<Document> documentList = [
    Document(
      name: 'Desktop',
      dateModified: DateTime.now(),
      isFile: false,
      childData: [
        Document(
          name: 'projects',
          dateModified: DateTime.now(),
          isFile: false,
          childData: [
            Document(
              name: 'flutter_app',
              dateModified: DateTime.now(),
              isFile: false,
              childData: [
                Document(
                  name: 'README.md',
                  dateModified: DateTime.now(),
                  isFile: true,
                ),
                Document(
                  name: 'pubspec.yaml',
                  dateModified: DateTime.now(),
                  isFile: true,
                ),
                Document(
                  name: 'pubspec.lock',
                  dateModified: DateTime.now(),
                  isFile: true,
                ),
                Document(
                  name: '.gitignore',
                  dateModified: DateTime.now(),
                  isFile: true,
                ),
                Document(
                  name: 'lib',
                  dateModified: DateTime.now(),
                  isFile: false,
                  childData: [
                    Document(
                      name: 'main.dart',
                      dateModified: DateTime.now(),
                      isFile: true,
                    ),
                  ],
                ),
              ],
            ),
          ],
        ),
        Document(
          name: 'test.sh',
          dateModified: DateTime.now(),
          isFile: true,
        ),
        Document(
          name: 'image.png',
          dateModified: DateTime.now(),
          isFile: true,
        ),
        Document(
          name: 'image2.png',
          dateModified: DateTime.now(),
          isFile: true,
        ),
        Document(
          name: 'image3.png',
          dateModified: DateTime.now(),
          isFile: true,
        ),
      ],
    ),
  ];

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title ?? 'Tree View demo'),
      ),
      body: TreeView(
        startExpanded: false,
        children: _getChildList(documentList),
      ),
    );
  }

  List<Widget> _getChildList(List<Document> childDocuments) {
    return childDocuments.map((document) {
      if (!document.isFile) {
        return Container(
          margin: EdgeInsets.only(left: 8),
          child: TreeViewChild(
            parent: _getDocumentWidget(document: document),
            children: _getChildList(document.childData!),
          ),
        );
      }
      return Container(
        margin: const EdgeInsets.only(left: 4.0),
        child: _getDocumentWidget(document: document),
      );
    }).toList();
  }

  Widget _getDocumentWidget({required Document document}) => document.isFile
      ? _getFileWidget(document: document)
      : _getDirectoryWidget(document: document);

  DirectoryWidget _getDirectoryWidget({required Document document}) =>
      DirectoryWidget(
        directoryName: document.name,
        lastModified: document.dateModified,
      );

  FileWidget _getFileWidget({required Document document}) => FileWidget(
        fileName: document.name,
        lastModified: document.dateModified,
      );
}