Devextreme内置主题在React应用中不生效，求排查方案

问题现状 #

• 使用Devextreme 23.1.3 + React框架，测试页面包含DataGrid，未引入本地SCSS/CSS文件
• 在index.html中添加了以下主题引用：

<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/23.1.5/css/dx.contrast.css" />

• Chrome网络面板显示加载了以下文件，但页面未应用Darkmoon主题：
  • https://cdn3.devexpress.com/jslib/23.1.5/css/dx.darkmoon.css
  • https://fonts.googleapis.com/css?family=Roboto:300,400,500,700
  • https://fonts.googleapis.com/earlyaccess/notokufiarabic.css

测试页面代码如下：

import React, { useState, useEffect, useRef } from 'react';
import DataGrid, { HeaderFilter, Editing, Paging, Pager, FilterRow, SearchPanel, StateStoring, Column, Scrolling } from 'devextreme-react/data-grid';
import {stringify} from "flatted";
//import 'devextreme/dist/css/dx.light.css';
//import './meters.scss';

const MetersPage = () => {
  const [data, setData] = useState([]); // Manage the data state
  const [filterValues, setFilterValues] = useState("");
  const dataGridRef = useRef(null);

  /*
  const applyFilter = () => {
    let values = filterValues.replace(/\s+/g, "").split(',');
    if (dataGridRef.current) {
      dataGridRef.current.instance.columnOption("EXTNL_MTR_ID", "filterValues", values);
    }
  };

  const clearFilter = () => {
    setFilterValues(""); // Clear the filter values
    if (dataGridRef.current) {
      dataGridRef.current.instance.columnOption("EXTNL_MTR_ID", "filterValues", null);
    }
  };
*/

  const fetchData = () => {
    // Make an API call to fetch data from the Django backend
    fetch('https://vm-devmdms02/meters2/')
      .then((response) => response.json())
      .then((data) => setData(data))
      .catch((error) => {
        console.error(error);
      });
  };

  const handleSave = (changes: any) => {
    // Clone the changes object to avoid modifying the original object
    const clonedChanges = { ...changes };

    // Remove properties with circular references
    const serializedData = stringify(clonedChanges);

    // Make an API call to save the modified changes in the Django backend
    fetch('https://vm-devmdms02/meters2/', {
      method: 'POST',
      body: serializedData,
      headers: {
        'Content-Type': 'application/json',
      },
    })
      .then((response) => response.json())
      .then(() => {
        // On success, fetch updated data and refresh the grid
        fetchData();
      });
  };

  useEffect(() => {
    fetchData(); // Fetch data on component mount
  }, []);

  return (
  <div>
    < DataGrid
      ref={dataGridRef}
      dataSource={data} 
      showBorders={true} 
      remoteOperations={true}
      onSaving={handleSave}
    >
      <Editing
          mode="cell"
          allowAdding={true}
          allowUpdating={true}
          allowDeleting={true}
          useIcons={true}/>
        <FilterRow visible={true} />
        <HeaderFilter allowSearch={true} />
        <Column
          dataField='DMI_DEVICE'
          caption='DMI_DEVICE'
        />
        <Column
          dataField='EXTNL_MTR_ID'
          caption='EXTNL_MTR_ID'
        />
        <Column
          dataField='DEVICE_NAME'
          caption='DEVICE_NAME'
        />
        <Column
          dataField='EIS_DEV_TYPE'
          caption='EIS_DEV_TYPE'
        />

        <Column
          dataField='DMI_RCDR_SP_NM'
          caption='DMI_RCDR_SP_NM'
        />
        <Column
          dataField='DMI_DP_MDM'
          caption='DMI_DP_MDM'
        />
        <Column
          dataField='DMI_DP'
          caption='DMI_DP'
        />
        <Column
          dataField='DMI_MTR'
          caption='DMI_MTR'
        />
        <Column
          dataField='DMI_MTR_CFG'
          caption='DMI_MTR_CFG'
        />
        <SearchPanel visible={true}/>
        <Paging defaultPageSize={10} />
        <StateStoring enabled={true} type={"localStorage"}/>
        <Pager showPageSizeSelector={true} showInfo={true} />
      </ DataGrid>
    </ div>
  );
};

export default MetersPage;

错误点分析 #

1. 版本不匹配：项目依赖的Devextreme是23.1.3，但CDN加载的样式文件是23.1.5版本，版本不一致会导致样式规则不兼容，无法正确应用主题。
2. 主题引用错误：你想要应用Darkmoon主题，但index.html中引用的是dx.contrast.css，网络中出现的dx.darkmoon.css可能是被其他依赖自动引入，导致多个主题样式冲突，最终生效的不是目标主题。
3. 潜在的默认主题引入：Devextreme React组件可能默认会引入基础主题（如light），如果多个主题文件同时加载，后加载的样式会覆盖先加载的，导致目标主题不生效。

解决步骤 #

1. 统一版本：将index.html中的主题CDN链接版本改为23.1.3，与项目依赖版本一致，同时直接引用Darkmoon主题：

<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/23.1.3/css/dx.darkmoon.css" />

2. 清理多余主题：检查项目中是否有其他地方（如package.json依赖、配置文件）自动引入了其他主题，确保只保留目标主题的引用。
3. 调整加载顺序：确保主题样式文件在Devextreme组件脚本之前加载，保证样式能优先应用到组件上。
4. 清除浏览器缓存：Chrome的缓存可能保留了旧的样式文件，清除缓存后重新加载页面测试。

内容的提问来源于stack exchange，提问作者Gregory Williams