Question

我尝试更新指向azure-devops-ui/Filter的功能组件。我正在使用azure-devops-extension-sdk来返回异步响应，以便使用此组件：
https://developer.microsoft.com/en-us/azure-devops/components/filter 在Azure DevOps上的WorkItem中

我已经分别使用this.state / componentDidMount和useState / useEffect使用基于类和函数的组件进行编码。我关注了this SO post。

但是，我只能重新渲染状态。更新状态后，类或功能组件中的UI组件都不会更新。

我有两个版本的代码，它们都等待响应并成功更新状态。但是，两个都不会等待UI的渲染。

常规组件：

import {
    IWorkItemChangedArgs,
    IWorkItemFieldChangedArgs,
    IWorkItemFormService,
    IWorkItemLoadedArgs,
    WorkItemTrackingServiceIds,
  } from "azure-devops-extension-api/WorkItemTracking";

import * as React from "react";
import * as SDK from "azure-devops-extension-sdk";

import { Header } from "azure-devops-ui/Header";
import { Page } from "azure-devops-ui/Page";

import { Filter, getKeywordFilterItem } from "azure-devops-ui/Filter";
import { IListBoxItem } from "azure-devops-ui/ListBox";
import { AggregateItemProvider } from "azure-devops-ui/Utilities/AggregateItemProvider";
import {
    Filter as FilterStore,
    FILTER_CHANGE_EVENT,
    IFilterState
} from "azure-devops-ui/Utilities/Filter";
import { GroupedItemProvider } from "azure-devops-ui//Utilities/GroupedItemProvider";
import { groupedItems, groups, statusItems } from "./data";
        export class WorkItemComponent extends React.Component<{} & ExtendedProps, any> {

    private provider: AggregateItemProvider<IListBoxItem>;

    private filterStore = new FilterStore();

    private textoStore = "second";

    private groupedProvider = new GroupedItemProvider([], [], true);
    private filterItems = [
        getKeywordFilterItem(this.filterStore),
        { name: "Status", id: "status", items: statusItems, filterItemKey: "status" },
        {
            name: "Group Items",
            id: "groupItems",
            items: this.groupedProvider,
            filterItemKey: "groupItems"
        }
    ];

    constructor(props: {}) {
        super(props);
        this.provider = new AggregateItemProvider<IListBoxItem>();
        this.groupedProvider.push(...groupedItems);
        this.groupedProvider.pushGroups(...groups);
        this.provider.push(statusItems);
        this.provider.push(this.groupedProvider);


        if(this.props.pdata==="first")
        this.filterStore = new FilterStore(
          {defaultState: {    groupItems: {        value: [this.props.pdata,this.textoStore]    }}} 
          );
          else
          this.filterStore = new FilterStore(
            {defaultState: {    groupItems: {        value: [this.textoStore,this.props.pdata,]    }}} 
            );


          this.filterStore.subscribe(this.onFilterChanged, FILTER_CHANGE_EVENT);


        this.state = {
            //currentState: ""
            currentState: JSON.stringify(this.filterStore.getState(), null, 4)
        };

    }

    public render():JSX.Element {

        return (
            <Page className="sample-hub flex-grow">
                <Header title="Filter" />
                <div className="page-content">
                <Filter 
                    filterStore={this.filterStore}
                    filterItems={this.filterItems}
                    items={this.provider}
                />
                    <div style={{ marginTop: "16px" }} className="monospaced-text">
                        <span>Current state:</span>
                        <span>{this.state.currentState}</span>
                        <span>{this.props.pdata}</span>
                    </div>
                </div>
            </Page>
        );
    }

    private onFilterChanged = (changedState: IFilterState) => {
        this.setState({
            currentState: JSON.stringify(this.filterStore.getState(), null, 4)
        });
        this.onFilterChangedExtended(JSON.stringify(this.filterStore.getState(), null, 4))
    };

    private async onFilterChangedExtended(estadoActual: string) {
        const workItemFormService = await SDK.getService<IWorkItemFormService>(
          WorkItemTrackingServiceIds.WorkItemFormService
        );

        workItemFormService.setFieldValue(SDK.getConfiguration().witInputs.FieldName, estadoActual);

      }

第一个在useFunction组件中具有useState和useEffect的调用者：

        import { WorkItemComponent } from "./WorkItemComponent";

  const WorkItemFilterAsync: React.FC = props => {

    let respuestaAsync="";

    const [data, setData] = React.useState<string>('');
    React.useEffect(() => {
    const fetchdata = async() =>{
      const result = await fngetFieldName()

         setData(result);

    }      
      // Execute the created function directly
      fetchdata();

    }, []);


    async function fngetFieldName(): Promise<string> {
      const workItemFormService = await SDK.getService<IWorkItemFormService>(
        WorkItemTrackingServiceIds.WorkItemFormService
      );

      const respuesta = workItemFormService.getFieldValue(SDK.getConfiguration().witInputs.FieldName);
      respuestaAsync = (await respuesta).toString();
      return JSON.stringify(respuesta);
    }
  return <WorkItemComponent pdata={data}/>
}
export default WorkItemFilterAsync;

第二个在类上具有componentDidMount的调用者：

import {
    IWorkItemChangedArgs,
    IWorkItemFieldChangedArgs,
    IWorkItemFormService,
    IWorkItemLoadedArgs,
    WorkItemTrackingServiceIds,
  } from "azure-devops-extension-api/WorkItemTracking";


import * as React from "react";
import { showRootComponent } from "../../Common";
import * as SDK from "azure-devops-extension-sdk";

import { WorkItemComponent } from "./WorkItemComponent";

//const WorkItemComponent = React.lazy (() => import('./WorkItemComponent'));


class WorkItemFilter extends React.Component{
    state = {
        externalData: false,
      };

      public componentDidMount() {
          this.onLoadExtended();
    }

    render():JSX.Element {

            return(

                <div className="page-content">
                    {this.state.externalData ? <WorkItemComponent pdata="first"/> : <WorkItemComponent pdata="third"/>}
                </div>

            );
        }


        private async onLoadExtended() {
            const workItemFormService = await SDK.getService<IWorkItemFormService>(
              WorkItemTrackingServiceIds.WorkItemFormService
            );

            let varaux = workItemFormService.getFieldValue(SDK.getConfiguration().witInputs.FieldName);

            if ((await varaux).toString()!=="")
            {

                this.setState({
                    externalData: true,
                });

            }

          }


}


  showRootComponent(<WorkItemFilter />);

这是父组件：

export function showRootComponent(component: React.ReactElement<any>) {
    ReactDOM.render(component, document.getElementById("root"));
}

Azure Dev Ops扩展（azure-devops-extension.json）的配置：

{
    "contributions": [
        {
            "id": "work-item-filter",
            "type": "ms.vss-work-web.work-item-form-control",
            "description": "Custom Filter",
            "targets": [
                "ms.vss-work-web.work-item-form"
            ],
            "properties": {
                "name": "BHD Filter",
                "uri": "dist/WorkItemFilter/WorkItemFilter.html",
                "height": 600,
                "inputs": [
                    {
                        "id":"FieldName",
                        "name": "Select the field for this control.",
                        "type": "WorkItemField",
                        "properties": {
                            "workItemFieldTypes": ["String", "PlainText", "HTML"]
                        },
                        "validation": {
                            "dataType": "String",
                            "isRequired": true
                        }

我还尝试将ReactDOM.render放在浏览器事件中，但是我不能这样做，因为UI扩展需要一个字段来保存数据：

Answer 1

使用新的React Hooks编写功能性React组件非常简单。在下面的示例中，我正在使用"${command:PickProcess}"和useState。 useEffect钩子在基于类的React组件中与useState同义。 this.state/this.setState挂钩类似于useEffect + componentDidMount。它也可以成为componentDidUpdate。

代码执行的方式是从上到下。因为它是功能性的，所以它将运行一次并使用在componentDidUnmount的参数处设置的默认状态进行渲染。它不会阻止在useState函数中从API获取数据。因此，您需要能够在没有数据的情况下处理加载。每当useEffect或props.apiConfig发生更改时，组件都会重新渲染，并且所有props.id都会重新渲染。 如果useEffect和useEffect在首次运行后确实发生更改，它只会调用props.apiConfig。唯一讨厌的部分是props.id不能是{{ 1}}函数，因此您必须不使用useEffect来调用函数async。 API接收到数据后，会将数据存储在getDataWrapper中，这将触发组件的重新呈现。

总结：

使用默认状态渲染一次
- 呼叫await，后者呼叫state
- 返回初始值为useEffect的组件
一旦API通过getDataWrapper / useState函数接收到数据，请通过useEffect设置状态并将getDataWrapper设置为setState
重新呈现isLoading现在包含的具有更新后值的组件
- 避免使用false控制路径，因为setState的第二个参数中的值未更改。（例如：useEffect和useEffect）。

props.apiConfig

承诺解决后如何重新渲染React组件？ |如何阻止渲染直到数据加载？

1 个答案: