bukan penggunaan siklus hidup reaksi yang tepat

Saya memiliki komponen web Sharepoint Framework yang pada dasarnya memiliki bilah sisi properti tempat saya dapat memilih Daftar Sharepoint, dan berdasarkan pilihan itu akan membuat item daftar dari daftar itu menjadi Komponen Daftar Detail UI Office.

Saat saya men-debug, panggilan REST semuanya baik-baik saja, namun masalahnya adalah saya tidak pernah menampilkan data apa pun di layar.

jadi jika saya memilih GenericList, ia harus menanyakan Daftar Generik, jika saya memilih Direktori, ia harus menanyakan daftar Direktori, namun ketika saya memilih Direktori, ia masih mengatakan bahwa pilihannya adalah GenericList, bukan direktori.

Ini adalah kode komponen web saya

import * as React from "react";
import * as ReactDom from "react-dom";
import { Version } from "@microsoft/sp-core-library";
import {
  BaseClientSideWebPart,
  IPropertyPaneConfiguration,
  PropertyPaneTextField,
  PropertyPaneDropdown,
  IPropertyPaneDropdownOption,
  IPropertyPaneField,
  PropertyPaneLabel
} from "@microsoft/sp-webpart-base";

import * as strings from "FactoryMethodWebPartStrings";
import FactoryMethod from "./components/FactoryMethod";
import { IFactoryMethodProps } from "./components/IFactoryMethodProps";
import { IFactoryMethodWebPartProps } from "./IFactoryMethodWebPartProps";
import * as lodash from "@microsoft/sp-lodash-subset";
import List from "./components/models/List";
import { Environment, EnvironmentType } from "@microsoft/sp-core-library";
import IDataProvider from "./components/dataproviders/IDataProvider";
import MockDataProvider from "./test/MockDataProvider";
import SharePointDataProvider from "./components/dataproviders/SharepointDataProvider";

export default class FactoryMethodWebPart extends BaseClientSideWebPart<IFactoryMethodWebPartProps> {
  private _dropdownOptions: IPropertyPaneDropdownOption[];
  private _selectedList: List;
  private _disableDropdown: boolean;
  private _dataProvider: IDataProvider;
  private _factorymethodContainerComponent: FactoryMethod;

  protected onInit(): Promise<void> {
    this.context.statusRenderer.displayLoadingIndicator(this.domElement, "Todo");

    /*
    Create the appropriate data provider depending on where the web part is running.
    The DEBUG flag will ensure the mock data provider is not bundled with the web part when you package the
     solution for distribution, that is, using the --ship flag with the package-solution gulp command.
    */
    if (DEBUG && Environment.type === EnvironmentType.Local) {
      this._dataProvider = new MockDataProvider();
    } else {
      this._dataProvider = new SharePointDataProvider();
      this._dataProvider.webPartContext = this.context;
    }

    this.openPropertyPane = this.openPropertyPane.bind(this);

    /*
    Get the list of tasks lists from the current site and populate the property pane dropdown field with the values.
    */
    this.loadLists()
      .then(() => {
        /*
         If a list is already selected, then we would have stored the list Id in the associated web part property.
         So, check to see if we do have a selected list for the web part. If we do, then we set that as the selected list
         in the property pane dropdown field.
        */
        if (this.properties.spListIndex) {
          this.setSelectedList(this.properties.spListIndex.toString());
          this.context.statusRenderer.clearLoadingIndicator(this.domElement);
        }
      });

    return super.onInit();
  }

  // render method of the webpart, actually calls Component
  public render(): void {
    const element: React.ReactElement<IFactoryMethodProps > = React.createElement(
      FactoryMethod,
      {
        spHttpClient: this.context.spHttpClient,
        siteUrl: this.context.pageContext.web.absoluteUrl,
        listName: this._dataProvider.selectedList === undefined ? "GenericList" : this._dataProvider.selectedList.Title,
        dataProvider: this._dataProvider,
        configureStartCallback: this.openPropertyPane
      }
    );

    // reactDom.render(element, this.domElement);
    this._factorymethodContainerComponent = <FactoryMethod>ReactDom.render(element, this.domElement);

  }

  // loads lists from the site and fill the dropdown.
  private loadLists(): Promise<any> {
    return this._dataProvider.getLists()
      .then((lists: List[]) => {
        // disable dropdown field if there are no results from the server.
        this._disableDropdown = lists.length === 0;
        if (lists.length !== 0) {
          this._dropdownOptions = lists.map((list: List) => {
            return {
              key: list.Id,
              text: list.Title
            };
          });
        }
      });
  }

  protected get dataVersion(): Version {
    return Version.parse("1.0");
  }

  protected onPropertyPaneFieldChanged(propertyPath: string, oldValue: any, newValue: any): void {
    /*
    Check the property path to see which property pane feld changed. If the property path matches the dropdown, then we set that list
    as the selected list for the web part.
    */
    if (propertyPath === "spListIndex") {
      this.setSelectedList(newValue);
    }

    /*
    Finally, tell property pane to re-render the web part.
    This is valid for reactive property pane.
    */
    super.onPropertyPaneFieldChanged(propertyPath, oldValue, newValue);
  }

  // sets the selected list based on the selection from the dropdownlist
  private setSelectedList(value: string): void {
    const selectedIndex: number = lodash.findIndex(this._dropdownOptions,
      (item: IPropertyPaneDropdownOption) => item.key === value
    );

    const selectedDropDownOption: IPropertyPaneDropdownOption = this._dropdownOptions[selectedIndex];

    if (selectedDropDownOption) {
      this._selectedList = {
        Title: selectedDropDownOption.text,
        Id: selectedDropDownOption.key.toString()
      };

      this._dataProvider.selectedList = this._selectedList;
    }
  }


  // we add fields dynamically to the property pane, in this case its only the list field which we will render
  private getGroupFields(): IPropertyPaneField<any>[] {
    const fields: IPropertyPaneField<any>[] = [];

    // we add the options from the dropdownoptions variable that was populated during init to the dropdown here.
    fields.push(PropertyPaneDropdown("spListIndex", {
      label: "Select a list",
      disabled: this._disableDropdown,
      options: this._dropdownOptions
    }));

    /*
    When we do not have any lists returned from the server, we disable the dropdown. If that is the case,
    we also add a label field displaying the appropriate message.
    */
    if (this._disableDropdown) {
      fields.push(PropertyPaneLabel(null, {
        text: "Could not find tasks lists in your site. Create one or more tasks list and then try using the web part."
      }));
    }

    return fields;
  }

  private openPropertyPane(): void {
    this.context.propertyPane.open();
  }

  protected getPropertyPaneConfiguration(): IPropertyPaneConfiguration {
    return {
      pages: [
        {
          header: {
            description: strings.PropertyPaneDescription
          },
          groups: [
            {
              groupName: strings.BasicGroupName,
              /*
              Instead of creating the fields here, we call a method that will return the set of property fields to render.
              */
              groupFields: this.getGroupFields()
            }
          ]
        }
      ]
    };
  }
}

Ini adalah kode komponen saya

//#region Imports
import * as React from "react";
import styles from "./FactoryMethod.module.scss";
import  { IFactoryMethodProps } from "./IFactoryMethodProps";
import {
  IDetailsListItemState,
  IDetailsNewsListItemState,
  IDetailsDirectoryListItemState,
  IDetailsAnnouncementListItemState,
  IFactoryMethodState
} from "./IFactoryMethodState";
import { IListItem } from "./models/IListItem";
import { IAnnouncementListItem } from "./models/IAnnouncementListItem";
import { INewsListItem } from "./models/INewsListItem";
import { IDirectoryListItem } from "./models/IDirectoryListItem";
import { escape } from "@microsoft/sp-lodash-subset";
import { SPHttpClient, SPHttpClientResponse } from "@microsoft/sp-http";
import { ListItemFactory} from "./ListItemFactory";
import { TextField } from "office-ui-fabric-react/lib/TextField";
import {
  DetailsList,
  DetailsListLayoutMode,
  Selection,
  buildColumns,
  IColumn
} from "office-ui-fabric-react/lib/DetailsList";
import { MarqueeSelection } from "office-ui-fabric-react/lib/MarqueeSelection";
import { autobind } from "office-ui-fabric-react/lib/Utilities";
import PropTypes from "prop-types";
//#endregion

export default class FactoryMethod extends React.Component<IFactoryMethodProps, IFactoryMethodState> {
  constructor(props: IFactoryMethodProps, state: any) {
    super(props);
    this.setInitialState();
  }


  // lifecycle help here: https://staminaloops.github.io/undefinedisnotafunction/understanding-react/
  //#region Mouting events lifecycle
  // the data returned from render is neither a string nor a DOM node.
  // it's a lightweight description of what the DOM should look like.
  // inspects this.state and this.props and create the markup.
  // when your data changes, the render method is called again.
  // react diff the return value from the previous call to render with
  // the new one, and generate a minimal set of changes to be applied to the DOM.
  public render(): React.ReactElement<IFactoryMethodProps> {
    if (this.state.hasError) {
      // you can render any custom fallback UI
      return <h1>Something went wrong.</h1>;
    } else {
      switch(this.props.listName) {
          case "GenericList":
            // tslint:disable-next-line:max-line-length
            return <this.ListMarqueeSelection items={this.state.DetailsListItemState.items} columns={this.state.columns} />;
          case "News":
            // tslint:disable-next-line:max-line-length
            return <this.ListMarqueeSelection items={this.state.DetailsNewsListItemState.items} columns={this.state.columns}/>;
          case "Announcements":
            // tslint:disable-next-line:max-line-length
            return <this.ListMarqueeSelection items={this.state.DetailsAnnouncementListItemState.items} columns={this.state.columns}/>;
          case "Directory":
            // tslint:disable-next-line:max-line-length
            return <this.ListMarqueeSelection items={this.state.DetailsDirectoryListItemState.items} columns={this.state.columns}/>;
          default:
            return null;
      }
    }
  }

  public componentDidCatch(error: any, info: any): void {
    // display fallback UI
    this.setState({ hasError: true });
    // you can also log the error to an error reporting service
    console.log(error);
    console.log(info);
  }



  // componentDidMount() is invoked immediately after a component is mounted. Initialization that requires DOM nodes should go here.
  // if you need to load data from a remote endpoint, this is a good place to instantiate the network request.
  // this method is a good place to set up any subscriptions. If you do that, don’t forget to unsubscribe in componentWillUnmount().
  // calling setState() in this method will trigger an extra rendering, but it is guaranteed to flush during the same tick.
  // this guarantees that even though the render() will be called twice in this case, the user won’t see the intermediate state.
  // use this pattern with caution because it often causes performance issues. It can, however, be necessary for cases like modals and
  // tooltips when you need to measure a DOM node before rendering something that depends on its size or position.
   public componentDidMount(): void {
    this._configureWebPart = this._configureWebPart.bind(this);
    this.readItemsAndSetStatus();
  }

  //#endregion
  //#region Props changes lifecycle events (after a property changes from parent component)
  // componentWillReceiveProps() is invoked before a mounted component receives new props.
  // if you need to update the state in response to prop
  // changes (for example, to reset it), you may compare this.props and nextProps and perform state transitions
  // using this.setState() in this method.
  // note that React may call this method even if the props have not changed, so make sure to compare the current
  // and next values if you only want to handle changes.
  // this may occur when the parent component causes your component to re-render.
  // react doesn’t call componentWillReceiveProps() with initial props during mounting. It only calls this
  // method if some of component’s props may update
  // calling this.setState() generally doesn’t trigger componentWillReceiveProps()
  public componentWillReceiveProps(nextProps: IFactoryMethodProps): void {
    if(nextProps.listName !== this.props.listName) {
      this.readItemsAndSetStatus();
    }
  }

  //#endregion
  //#region private methods
  private _configureWebPart(): void {
    this.props.configureStartCallback();
  }

  public setInitialState(): void {
    this.state = {
      hasError: false,
      status: this.listNotConfigured(this.props)
        ? "Please configure list in Web Part properties"
        : "Ready",
      columns:[],
      DetailsListItemState:{
        items:[]
      },
      DetailsNewsListItemState:{
        items:[]
      },
      DetailsDirectoryListItemState:{
        items:[]
      },
      DetailsAnnouncementListItemState:{
        items:[]
      },
    };
  }

  // reusable inline component
  private ListMarqueeSelection = (itemState: {columns: IColumn[], items: IListItem[] }) => (
      <div>
          <DetailsList
            items={ itemState.items }
            columns={ itemState.columns }
            setKey="set"
            layoutMode={ DetailsListLayoutMode.fixedColumns }
            selectionPreservedOnEmptyClick={ true }
            compact={ true }>
          </DetailsList>
      </div>
  )

  // read items using factory method pattern and sets state accordingly
  private readItemsAndSetStatus(): void {
    this.setState({
      status: "Loading all items..."
    });

    const factory: ListItemFactory = new ListItemFactory();
    factory.getItems(this.props.spHttpClient, this.props.siteUrl, this.props.listName)
    .then((items: any[]) => {

      var myItems: any = null;
      switch(this.props.listName) {
          case "GenericList":
              myItems = items as IListItem[];
              break;
          case "News":
              myItems = items as INewsListItem[];
              break;
          case "Announcements":
              myItems = items as IAnnouncementListItem[];
              break;
          case "Directory":
              myItems = items as IDirectoryListItem[];
              break;
      }

      const keyPart: string = this.props.listName === "GenericList" ? "" : this.props.listName;
        // the explicit specification of the type argument `keyof {}` is bad and
        // it should not be required.
        this.setState<keyof {}>({
          status: `Successfully loaded ${items.length} items`,
          ["Details" + keyPart + "ListItemState"] : {
            myItems
          },
          columns: buildColumns(myItems)
        });
    });
  }

  private listNotConfigured(props: IFactoryMethodProps): boolean {
    return props.listName === undefined ||
      props.listName === null ||
      props.listName.length === 0;
  }

  //#endregion
}

Saya pikir kode lainnya tidak diperlukan

Perbarui SharepointDataProvider.ts

import {
    SPHttpClient,
    SPHttpClientBatch,
    SPHttpClientResponse
  } from "@microsoft/sp-http";
  import { IWebPartContext } from "@microsoft/sp-webpart-base";
  import List from "../models/List";
  import IDataProvider from "./IDataProvider";

  export default class SharePointDataProvider implements IDataProvider {
      private _selectedList: List;
      private _lists: List[];
      private _listsUrl: string;
      private _listItemsUrl: string;
      private _webPartContext: IWebPartContext;

      public set selectedList(value: List) {
        this._selectedList = value;
        this._listItemsUrl = `${this._listsUrl}(guid'${value.Id}')/items`;
      }

      public get selectedList(): List {
        return this._selectedList;
      }

      public set webPartContext(value: IWebPartContext) {
        this._webPartContext = value;
        this._listsUrl = `${this._webPartContext.pageContext.web.absoluteUrl}/_api/web/lists`;
      }

      public get webPartContext(): IWebPartContext {
        return this._webPartContext;
      }

      // get all lists, not only tasks lists
      public getLists(): Promise<List[]> {
        // const listTemplateId: string = '171';
        // const queryString: string = `?$filter=BaseTemplate eq ${listTemplateId}`;
        // const queryUrl: string = this._listsUrl + queryString;
        return this._webPartContext.spHttpClient.get(this._listsUrl, SPHttpClient.configurations.v1)
          .then((response: SPHttpClientResponse) => {
            return response.json();
          })
          .then((json: { value: List[] }) => {
            return this._lists = json.value;
          });
      }
    }

Idataprovider.ts

import { IWebPartContext } from "@microsoft/sp-webpart-base";
import List from "../models/List";
import {IListItem} from "../models/IListItem";

interface IDataProvider {
  selectedList: List;
  webPartContext: IWebPartContext;
  getLists(): Promise<List[]>;
}

export default IDataProvider;

person Luis Valencia    schedule 15.05.2018    source sumber
comment
apakah metode render Anda dipanggil dengan benar? dapatkah Anda mencatat this.props.listName dan mendapatkan nilai yang benar?   -  person azium    schedule 15.05.2018
comment
pertama kali sebenarnya tidak terdefinisi. screencast.com/t/kBChpQtLIs   -  person Luis Valencia    schedule 15.05.2018
comment
Sepertinya this._dataProvider.selectedList.Title tidak disetel dengan benar. Apakah Anda menggunakan new MockDataProvider(); atau new SharePointDataProvider();? Itu akan membantu Anda mempersempitnya.   -  person Chase DeAnda    schedule 15.05.2018
comment
Saya menggunakan meja kerja online sharepoint, jadi dengan menggunakan SharepointDataProvider, saya benar-benar bisa mendapatkan data. Saya akan menempelkan lebih banyak kode di atas   -  person Luis Valencia    schedule 15.05.2018
comment
izinkan saya membagikan kode saya di github, mungkin itu lebih mudah   -  person Luis Valencia    schedule 15.05.2018
comment
inilah metode saya saat ini, yang dapat dikompilasi tetapi tidak berfungsi dengan benar, github.com/levalencia/sp-dev-fx-webparts/tree/   -  person Luis Valencia    schedule 15.05.2018
comment
masuk akal jika pertama kali adalah undefined karena render akan dipanggil sebelum semua metode siklus hidup lainnya.   -  person azium    schedule 16.05.2018


Jawaban (2)


Saat nama daftar berubah, Anda memanggil readItemsAndSetStatus:

  public componentWillReceiveProps(nextProps: IFactoryMethodProps): void {
    if(nextProps.listName !== this.props.listName) {
      this.readItemsAndSetStatus();
    }
  }

Namun, readItemsAndSetStatus tidak mengambil parameter, dan terus menggunakan this.props.listName, yang belum berubah.

private readItemsAndSetStatus(): void {       
    ...
    const factory: ListItemFactory = new ListItemFactory();
    factory.getItems(this.props.spHttpClient, this.props.siteUrl, this.props.listName)
    ...
}

Coba lewati nextProps.listName ke readItemsAndSetStatus:

  public componentWillReceiveProps(nextProps: IFactoryMethodProps): void {
    if(nextProps.listName !== this.props.listName) {
      this.readItemsAndSetStatus(nextProps.listName);
    }
  }

Kemudian gunakan parameter masuk, atau default ke this.props.listName:

private readItemsAndSetStatus(listName): void {       
    ...
    const factory: ListItemFactory = new ListItemFactory();
    factory.getItems(this.props.spHttpClient, this.props.siteUrl, listName || this.props.listName)
    ...
}
person lux    schedule 24.05.2018
comment
bagaimana dengan ComponentDIdMount, saya juga menggunakan readItemAndSetStatus di sana tanpa parameter - person Luis Valencia; 24.05.2018
comment
@LuisValencia Anda pasti dapat meneruskan this.readItemAndSetStatus(this.props.listName) dalam CDM, yang akan lebih eksplisit daripada sekadar menetapkan default ke this.props.listName dalam panggilan factory.getItems jika tidak ada parameter yang diteruskan. Artinya, jika Anda melakukan default ke this.props.listName dalam panggilan itu, maka aman untuk tidak meneruskan apa pun, seperti yang Anda lakukan sekarang, di CDM, karena, defaultnya akan tetap this.props.listName. - person lux; 24.05.2018

Dalam "kode komponen web" pertama Anda, metode onInit() kembali sebelum loadLists() selesai:

onInit() {
  this.loadLists()  // <-- Sets this._dropdownOptions
    .then(() => {
      this.setSelectedList();
    });

  return super.onInit();  // <-- Doesn't wait for the promise to resolve
}

Artinya getGroupFields() mungkin tidak memiliki data untuk _dropdownOptions. Artinya getPropertyPaneConfiguration() mungkin tidak memiliki data yang benar.

Saya tidak yakin itu masalahnya, atau satu-satunya masalah. Saya tidak punya pengalaman apa pun dengan SharePoint, jadi anggap saja semua ini sepele.


Saya melihatnya di react-todo-basic mereka melakukan hal yang sama seperti Anda.

Namun, di tempat lain saya melihat orang-orang melakukan tindakan tambahan dalam Janji super.onInit:

person Reed Dunkle    schedule 23.05.2018