Issue updating a SharePoint list within a gallery using OnChange property

[marclotorto1]

Hello,

I am currently building an app for a client that utilizes a gallery and SharePoint Online list to replicate the repeating table functionality of InfoPath/SharePoint 2010. For each item in the table, I am collecting a link (single line text), the name of the link (single line text, also the Title field), the name of a reviewer (people picker), date reviewed (date picker), and a reviewed checkbox (Yes/No).

I utilize the OnChange property to update the change to each field on each edit with the Patch function. Example code:

OnChange: 

Patch('Links-Spare Parts', ThisItem,
   {Title: txtSPDocName.Text,
   Link: txtSPDocLink.Text,
   'Person Who Verified': drpSparePartsDocReviewer.Selected,
   'Date Verified': dteSparePartsReviewedDate.SelectedDate,
   ReviewCompleted: chkSparePartsReviewCompleted.Value,
   Section: "Spare Parts"});

The behavior works as expected when updated just the text input fields DocName and Link. But when I update the Reviewer people picker, date selector, or review complete check box, it clears the values in the Reviewer people picker and the date selector. The OnChange property isn't clearing or resetting those fields, just patching to the list. What's weirder is when I just set a label to the Reviewer.Selected.DisplayName, it shows the DisplayName as expected. So the data is there in the people picker, but the name doesn't show from the outside and get's cleared. Any ideas for a fix for this?

Some screenshots: 

When searching for name, and then selecting

After selecting the name - notice it pulls it into the label as selected, but clears the people picker box above

Same for the date picker

After selecting the date, the value in the picker clears but it shows that the date is still selected with the label

Thanks in advance

[RandyHayes]

@marclotorto1 

I would first change the formula you had to:

UpdateIf('Links-Spare Parts', ID=ThisItem.ID,
   {Title: txtSPDocName.Text,
   Link: txtSPDocLink.Text,
   'Person Who Verified': drpSparePartsDocReviewer.Selected,
   'Date Verified': dteSparePartsReviewedDate.SelectedDate,
   ReviewCompleted: chkSparePartsReviewCompleted.Value,
   Section: "Spare Parts"}
);

This will be more precice in that action.

As for the controls and their values after the update...this is going to depend on:

- the Default properties of the checkbox and datepicker

- the DefaultSelectedItems property of the combobox

- the Items property of the combobox

- the Items property of your Gallery.

So, if you can fill in those details, perhaps the answer will come from that.

[marclotorto1]

Thanks for the response Randy. I've updated all patch functions to UpdateIf.

My values for the other properties are as follows:

- the Default properties of the checkbox and datepicker - these were blank, I've updated themn to ThisItem.Reviewer and ThisItem.DateReviewed. This eliminated the clearing of the date picker, but the Reviewer picker is still clearing...

- the DefaultSelectedItems property of the combobox - this is blank

- the Items property of the combobox - it is Choices([@'Links-Spare Parts'].'Person Who Verified')

- the Items property of your Gallery - this is my SharePoint list filtered where the Parent ID 'Master ID' = the ID of these items, which are set on creation. It's a one to many relationship: Filter('Links-Spare Parts', varRecord.ID = MasterID).

I am now getting this error which has been popping up and I can't seem to find much after googling: 

Any ideas?

[RandyHayes]

@marclotorto1 

So the error you are seeing is that there is a conflict in the record.  This means that for some reason the record in the list has changed and you are trying to update with older record information. \

For the combobox, you will need to set the DefaultSelectedItems property.  Based on what I see, it should be ThisItem.'Person Who Verified'

[marclotorto1]

Hey Randy,

So I updated the DefaultSelectedItems to ThisItem.'Person Who Verified' and it accepted it. However now I am getting a super weird error where I am getting a ton of runtime errors on the OnChange property for the reviewer box - 

Seems similar to the issue before: 

These error will flicker and duplicate it anyway from 6-8 times in the OnCheck list. Any ideas? Thanks for your help.

[marclotorto1]

Walked away for about 15 mins and came back and now there's 483 runtime errors... would love some clarity if anyone else has run into this.

[RandyHayes · Accepted solution]

@marclotorto1 

Yes, this is because the Combobox OnChange action that you are using will happen because you are technically changing the selection in the combobox...so it runs your formula...which changes the selection (even though it is the same) and then runs the formula again...and again...and again!

Be cautious with Comboboxes and using the OnChange action as this is one of the few controls that will do what you are seeing.

I would suggest trying to avoid using any of the OnSomething actions in PowerApps except for very basic actions (and there are exceptions to this rule).  But, using those actions is very "program-like" and PowerApps is not a programming platform.  

However, working around this is going to be a combination of design choices and function.  

Typically the design choice is to say that you would have a specific "save" button/icon on each row and it is visible when a value is changed.  The user would then click on that save button/icon to THEN perform the formula you have.

Another option is to perform the saves by a button outside of the gallery to save them all, or have an automatic save running by - when the screen is changed or at specific times.

All design choices.

Functionality choices are to determine if the function of automatically saving (and thus producing data actions on every control) is needed.  If not, then consider the design choices above.  If so, then you need to work around the OnChange situation of a combobox.  That can be done with "flag" variables to exclude actions when they are not needed...it's a hassle to deal with though.

[marclotorto1]

Thanks for the indepth response Randy. Will work on this and get back to you. Thanks again.

[RandyHayes]

@marclotorto1 

Happy to help!