cancel
Showing results for 
Search instead for 
Did you mean: 
Reply
shadowfox
Frequent Visitor

Change in PCF Controls load null data on initial load

Recently a control I have had published for quiet some time started to break (in July). This code base has not changed and has been working fine for some time. Trying to determine what update is causing this change in behavior. The issue is on initial load the field mapped to the control shows null data. But if you do a post back again (F5) it will work on the second load and if you exit the record and re-open it will work fine. Trying to understand why all of a sudden it's displaying null on initial load. As I have said - the code hasn't changed since Mar 18, 2020.  This is a modified version of the PeoplePicker control -

 

import { IInputs, IOutputs } from "./generated/ManifestTypes";
import * as React from 'react';
import * as ReactDOM from 'react-dom';
import { PeoplePickerTypes, IPeopleProps, IPeoplePersona } from './Peoplepicker';

export class OfficeUIFabricReactPeoplePicker implements ComponentFramework.StandardControl<IInputs, IOutputs> {
	private theContainer: HTMLDivElement;
	private notifyOutputChanged: () => void;
	private _context: ComponentFramework.Context<IInputs>;
	private props: IPeopleProps = {
		//tableValue: this.numberFacesChanged.bind(this),
		peopleList: this.peopleList.bind(this),
	}

	/**
	 * Empty constructor.
	 */
	constructor() {

	}

	/**
	 * Used to initialize the control instance. Controls can kick off remote server calls and other initialization actions here.
	 * Data-set values are not initialized here, use updateView.
	 * @Param context The entire property bag available to control via Context Object; It contains values as set up by the customizer mapped to property names defined in the manifest, as well as utility functions.
	 * @Param notifyOutputChanged A callback method to alert the framework that the control has new outputs ready to be retrieved asynchronously.
	 * @Param state A piece of data that persists in one session for a single user. Can be set at any point in a controls life cycle by calling 'setControlState' in the Mode interface.
	 * @Param container If a control is marked control-type='standard', it will receive an empty div element within which it can render its content.
	 */
	public init(context: ComponentFramework.Context<IInputs>, notifyOutputChanged: () => void, state: ComponentFramework.Dictionary, container: HTMLDivElement) {
		// Add control initialization code
		this.notifyOutputChanged = notifyOutputChanged;
		this._context = context;
		this.theContainer = container;
	}


	/**
	 * Called when any value in the property bag has changed. This includes field values, data-sets, global values such as container height and width, offline status, control metadata values such as label, visible, etc.
	 * @Param context The entire property bag available to control via Context Object; It contains values as set up by the customizer mapped to names defined in the manifest, as well as utility functions
	 */
	public async updateView(context: ComponentFramework.Context<IInputs>) {
		// Add code to update control view
		this.props.context = context;
		if (context.parameters.peoplePicker.raw !== null) {
			if (context.parameters.peoplePicker.raw!.indexOf("text") > 1) {
				this.props.preselectedpeople = JSON.parse(context.parameters.peoplePicker.raw!);
			}
		}

		ReactDOM.render(
			React.createElement(
				PeoplePickerTypes,
				this.props
			),
			this.theContainer
		);

	}

	/** 
	 * It is called by the framework prior to a control receiving new data. 
	 * @returns an object based on nomenclature defined in manifest, expecting object[s] for property marked as “bound” or “output”
	 */
	public getOutputs(): IOutputs {
		return {
			peoplePicker: JSON.stringify(this.props.people)
		};
	}

	private peopleList(newValue: IPeoplePersona[]) {
		if (this.props.people !== newValue) {
			if (newValue.length === 0) {
				this.props.people = undefined;
			}
			else {
				this.props.people = newValue;
			}

			this.notifyOutputChanged();
		}
	}

	/** 
	 * Called when the control is to be removed from the DOM tree. Controls should use this call for cleanup.
	 * i.e. cancelling any pending remote calls, removing listeners, etc.
	 */
	public destroy(): void {
		// Add code to cleanup control if necessary
		ReactDOM.unmountComponentAtNode(this.theContainer);
	}
}

 

1 ACCEPTED SOLUTION

Accepted Solutions

No, the "null first, value second" thing is something I've seen before, that's why I knew to guess it. I am not sure how to reliably reproduce (or avoid) it, which is why I just take approaches that circumvent it. So again, make sure your nullcheck is safe (you already have a !== null, so that should safely avoid any exceptions) then add in a line right before your reactdom.render, basically the same thing you are doing in Dispose:

 

ReactDOM.unmountComponentAtNode(this.theContainer);

 

This will let your component run once, with a null string, which will render nothing in the picker. But then when updateView gets called again and has a value, it will unload that empty version of the control and reload with an actual value.

View solution in original post

18 REPLIES 18
cchannon
Super User
Super User

Nothing is jumping out at me as problematic in this code. What do you see when you debug the control using browser developer tools?

DianaBirkelbach
Super User
Super User

Hi @shadowfox 

 

 I don't know if that has something to do with it, but what's the reason of searching the "text" inside the peoplePicker parameter?

context.parameters.peoplePicker.raw!.indexOf("text")

 

If after the reload it works, maybe the first render triggers the "peopleList" witch changes the value.


Otherweise, I agree with @cchannon  , it depends on which values are passed to updateView when it's triggered. 

 

Kind regards,

Diana

 

Kind regards,
Diana
----------
Please click "Accept as Solution" if my post answered your question so that others may find it more quickly. If you found this post helpful consider giving it a "Thumbs Up."

@cchannon When using the debug tool - on the initial load when it first hits the updateview this is what I see (image below which shows the field being null) -

shadowfox_0-1628085445069.png

But then on the second call of the updateview is shows the data but at this point it's not rendering.

shadowfox_1-1628085522565.png

If I close the page and re-open the initial load this time has a value - 

shadowfox_2-1628085618220.png

This is the part that makes no sense to me. The fact on a cold load - the initial is null but then after closing and re-opening it's fine. As I said - this has been working wonderfully for over a year with no issues but this behavior just started. I did also try to update my npm packages and see if that fixed it but no luck.

 

Thanks.

 

@DianaBirkelbach thanks for the reply! The indexOf("text") is verifying the JSON has the label text in it to get the label for the control. Otherwise if text is missing, then the JSON main part is malformed and won't work. Hope that helps better explain that. Sadly - with the issue I'm having - I'm not hitting this part since the field is passing null on the initial cold load.

 

Thanks!

Hi @shadowfox , 

 

Now I'm making some wild guessing.
Maybe the "this.props" makes some trouble because the props is reserved in react, and the PCFs are based on react. Thinking of it, you actually don't need the private "props" in your class, which you also pass as a reference to the component PeoplePickerTypes as props. I also suppose that the changing of the content inside the props won't be reflected, since you render the PeoplePickerTypes with the same reference of the props, but you change the content (props should be immutable).

In your class, you only need the value (in your case the people).
So I suggest, not to define a private "props" in your class. The props you pass to your PeoplePickerTypes can be defined just where you call the render function. All you need to keep in the class is the value for people, and the function itself (peopleList).

 

I've also saw that the updateView is declared "async". Not so sure if it's supposed to work that way, but I also don't see where you have the await. I suggest to delete the async.

 

It the explanation is not clear enough, please let me know.

Hope it helps.

 

Kind regards,

Diana

Kind regards,
Diana
----------
Please click "Accept as Solution" if my post answered your question so that others may find it more quickly. If you found this post helpful consider giving it a "Thumbs Up."

@shadowfox When you say, "the field is passing null" do you mean

context.parameters.peoplePicker.raw

is coming through as null even though the attrib does contain a JSON value?

@cchannon Yes - that was on the debugger image I grabbed. The context.parameters.peoplePicker.raw is null on initial cold load. Very crazy - this is something new I'm experiencing. 

@DianaBirkelbach thanks for the reply. You did catch something I was trying just to see if it made a difference but it didn't. Here is the original code for that part. I was initially just using context.parameters.peoplePicker.raw but wanted to see if the this.props.context made any difference (mostly because I'm stuck and nothing else I tried worked so figured I'd try it just to rule it out). As for the async - this was initially developed as part of the PCF Gallery control - People Picker | PCF Gallery. I have modified the React code quiet a bit to handle any entity and fixed an issue with the async promise. But the index.ts page has been left untouched since I pulled it down. What's blogging my head its been working for over a year now just fine. This makes me think something with how controls are being rendered on cold load and binding has been changed. Thanks for the help!

public async updateView(context: ComponentFramework.Context<IInputs>) {
		// Add code to update control view
		this.props.context = context;
		if (context.parameters.peoplePicker.raw !== null) {
			if (context.parameters.peoplePicker.raw!.indexOf("text") > 1) {
				this.props.preselectedpeople = JSON.parse(context.parameters.peoplePicker.raw!);
			}
		}

		ReactDOM.render(
			React.createElement(
				PeoplePickerTypes,
				this.props
			),
			this.theContainer
		);

	}

 

Well, updateView gets called multiple times onLoad (at least two, could be more depending on what's happening on your form) and you can even force it to fire with Client Script by using the fireOnChange() function.

 

So try debugging again and just put your breakpoint at the top of updateView. Is contex.parameters.peoplePicker null every time updateView gets called, or maybe just the first time?

Helpful resources

Announcements

Power Platform Connections - Episode 7 | March 30, 2023

Episode Seven of Power Platform Connections sees David Warner and Hugo Bernier talk to Dian Taylor, alongside the latest news, product reviews, and community blogs.     Use the hashtag #PowerPlatformConnects on social media for a chance to have your work featured on the show.     

Announcing | Super Users - 2023 Season 1

Super Users – 2023 Season 1    We are excited to kick off the Power Users Super User Program for 2023 - Season 1.  The Power Platform Super Users have done an amazing job in keeping the Power Platform communities helpful, accurate and responsive. We would like to send these amazing folks a big THANK YOU for their efforts.      Super User Season 1 | Contributions July 1, 2022 – December 31, 2022  Super User Season 2 | Contributions January 1, 2023 – June 30, 2023    Curious what a Super User is? Super Users are especially active community members who are eager to help others with their community questions. There are 2 Super User seasons in a year, and we monitor the community for new potential Super Users at the end of each season. Super Users are recognized in the community with both a rank name and icon next to their username, and a seasonal badge on their profile.    Power Apps  Power Automate  Power Virtual Agents  Power Pages  Pstork1*  Pstork1*  Pstork1*  OliverRodrigues  BCBuizer  Expiscornovus*  Expiscornovus*  ragavanrajan  AhmedSalih  grantjenkins  renatoromao    Mira_Ghaly*  Mira_Ghaly*      Sundeep_Malik*  Sundeep_Malik*      SudeepGhatakNZ*  SudeepGhatakNZ*      StretchFredrik*  StretchFredrik*      365-Assist*  365-Assist*      cha_cha  ekarim2020      timl  Hardesh15      iAm_ManCat  annajhaveri      SebS  Rhiassuring      LaurensM  abm      TheRobRush  Ankesh_49      WiZey  lbendlin      Nogueira1306  Kaif_Siddique      victorcp  RobElliott      dpoggemann  srduval      SBax  CFernandes      Roverandom  schwibach      Akser  CraigStewart      PowerRanger  MichaelAnnis      subsguts  David_MA      EricRegnier  edgonzales      zmansuri  GeorgiosG      ChrisPiasecki  ryule      AmDev  fchopo      phipps0218  tom_riha      theapurva  takolota     Akash17  momlo     BCLS776  Shuvam-rpa     rampprakash  ScottShearer     Rusk  ChristianAbata     cchannon  Koen5     a33ik   Heartholme     AaronKnox        Matren        Alex_10        Jeff_Thorpe        poweractivate        Ramole        DianaBirkelbach        DavidZoon        AJ_Z        PriyankaGeethik        BrianS        StalinPonnusamy        HamidBee        CNT        Anonymous_Hippo        Anchov        KeithAtherton        alaabitar        Tolu_Victor        KRider        sperry1625        IPC_ahaas      zuurg    rubin_boer   cwebb365   Dorrinda   G1124   Gabibalaban   Manan-Malhotra   jcfDaniel   WarrenBelz   Waegemma      If an * is at the end of a user's name this means they are a Multi Super User, in more than one community. Please note this is not the final list, as we are pending a few acceptances.  Once they are received the list will be updated. 

Microsoft Power Platform Conference | Registration Open | Oct. 3-5 2023

We are so excited to see you for the Microsoft Power Platform Conference in Las Vegas October 3-5 2023! But first, let's take a look back at some fun moments and the best community in tech from MPPC 2022 in Orlando, Florida.   Featuring guest speakers such as Charles Lamanna, Heather Cook, Julie Strauss, Nirav Shah, Ryan Cunningham, Sangya Singh, Stephen Siciliano, Hugo Bernier and many more.   Register today: https://www.powerplatformconf.com/   

Check out the new Power Platform Communities Front Door Experience!

We are excited to share the ‘Power Platform Communities Front Door’ experience with you!   Front Door brings together content from all the Power Platform communities into a single place for our community members, customers and low-code, no-code enthusiasts to learn, share and engage with peers, advocates, community program managers and our product team members. There are a host of features and new capabilities now available on Power Platform Communities Front Door to make content more discoverable for all power product community users which includes ForumsUser GroupsEventsCommunity highlightsCommunity by numbersLinks to all communities Users can see top discussions from across all the Power Platform communities and easily navigate to the latest or trending posts for further interaction. Additionally, they can filter to individual products as well.       Users can filter and browse the user group events from all power platform products with feature parity to existing community user group experience and added filtering capabilities.     Users can now explore user groups on the Power Platform Front Door landing page with capability to view all products in Power Platform.    Explore Power Platform Communities Front Door today. Visit Power Platform Community Front door to easily navigate to the different product communities, view a roll up of user groups, events and forums.

Welcome to the Power Apps Community

Welcome! Congratulations on joining the Microsoft Power Apps community! You are now a part of a vibrant group of peers and industry experts who are here to network, share knowledge, and even have a little fun! Now that you are a member, you can enjoy the following resources:   The Microsoft Power Apps Community Forums If you are looking for support with any part of Microsoft Power Apps, our forums are the place to go. They are titled "Get Help with Microsoft Power Apps " and there you will find thousands of technical professionals with years of experience who are ready and eager to answer your questions. You now have the ability to post, reply and give "kudos" on the Power Apps community forums! Make sure you conduct a quick search before creating a new post because your question may have already been asked and answered!   Microsoft Power Apps IdeasDo you have an idea to improve the Microsoft Power Apps experience, or a feature request for future product updates? Then the "Power Apps Ideas" section is where you can contribute your suggestions and vote for ideas posted by other community members. We constantly look to the most voted Ideas when planning updates, so your suggestions and votes will always make a difference.   Community Blog & NewsOver the years, more than 600 Power Apps Community Blog Articles have been written and published by our thriving community. Our community members have learned some excellent tips and have keen insights on building Power Apps. On the Power Apps Community Blog, read the latest Power Apps related posts from our community blog authors around the world. Let us know if you would like to become an author and contribute your own writing — everything Power Apps related is welcome!   Power Apps Samples, Learning and Videos GalleriesOur galleries have a little bit of everything to do with Power Apps. Our galleries are great for finding inspiration for your next app or component. You can view, comment and kudo the apps and component gallery to see what others have created! Or share Power Apps that you have created with other Power Apps enthusiasts. Along with all of that awesome content, there is the Power Apps Community Video & MBAS gallery where you can watch tutorials and demos by Microsoft staff, partners, and community gurus in our community video gallery.   Again, we are excited to welcome you to the Microsoft Power Apps community family! Whether you are brand new to the world of process automation or you are a seasoned Power Apps veteran. Our goal is to shape the community to be your ‘go to’ for support, networking, education, inspiration and encouragement as we enjoy this adventure together!   Let us know in the Community Feedback if you have any questions or comments about your community experience.To learn more about the community and your account be sure to visit our Community Support Area boards to learn more! We look forward to seeing you in the Power Apps Community!The Power Apps Team

Top Kudoed Authors
Users online (2,655)