How to write a patch formula to allow users to update existing list items in SP-integrated power apps form

[acoliva]

I created a SharePoint-integrated power apps form where I have added a second screen that collects product IDs and names from a gallery into a data table as well as concatenating service options from a combo box to a text label. My patch that adds a new item to the list works 100% fine but I am struggling on how to write a patch formula when user wants to update existing record by either adding more services/products or removing values.

This is what my screen looks like:

And below is the working patch formula to create a new item where

• Authorized Countries is a combo box on 1st screen with different data source
• Product Identifier is a multi-line text field in list that displays the collected data table values 
• Services Selected is also a mutli-line text field in list that displays the concatenated services in the text label 

ForAll(
Gallery1.AllItems.Checkbox1,
Collect(
ProductsSelected,ThisRecord)
);
Patch(
PATestMaster,
Defaults(PATestMaster),
{
'AuthorizedCountries' :ComboBox1.SelectedItems
};
SharePointForm1.Updates,
{
ProductIdentifier: Concat(ProductsSelected,ThisRecord.Value & " | "),
'Services Selected': ServicesDisplayed_TXT.Text
});
NewForm(SharePointForm1)

What formula would I create on if I added an "Update Item" button on this same screen, visible only when item's ID already exists so that any edits to product or services selection would populate back to the list?

[FLMike · Accepted solution]

Hello,

In your Patch there you see you say Default(XXX) which  means create new

You replace Defaults(xxx) which a pointer to the record you want to update

Example

Patch(XXX, LookUp(XXX, Id = IdfromScreen),

{ }

);

Your LookUp returns the record pointer so Patch knows what to update. You can do Title = "" or Number = Value or within reason anything that returns a single record to the LookUp

Cheers
If you like my answer, please Mark it as Resolved, and give it a thumbs up, so it can help others
Thank You
Michael Gernaey MCT | MCSE | MCP | Self-Contractor| Ex-Microsoft
https://gernaeysoftware.com
LinkedIn: https://www.linkedin.com/in/michaelgernaey

[acoliva]

Thanks for the response! Lookup makes sense but when I use it, it doesn't recognize any of my fields from the form. I tried ID and Title and also tried to reference them on the screen in a hidden text label instead of referring to the data card but the first value is not recognized in this syntax:

Patch(PATestMaster, LookUp(PATestMaster, Id = DataCardValue4.Text),

or

Patch(PATestMaster, LookUp(PATestMaster, Id = lblREFID.Text),

(also tried both ways with Title)

[FLMike]

Hello,

I would need to see your datacard and all its fields as well as that full syntax you typed and the error itself, please

[FLMike]

Here is my example

I have an edit form bound to TestList, and you can see my Patch. Works fine. Hence why I want to see your card and your full patch statement. Something is wrong with it for sure.

Cheers
If you like my answer, please Mark it as Resolved, and give it a thumbs up, so it can help others
Thank You
Michael Gernaey MCT | MCSE | MCP | Self-Contractor| Ex-Microsoft
https://gernaeysoftware.com
LinkedIn: https://www.linkedin.com/in/michaelgernaey

[acoliva]

My SharePoint form fields/data cards are not on the second screen . I provided the screen image for the second screen and patch in original post. My original patch for new item works correctly. 

I am hoping to use an update button on screen 2 when user edits existing list item.

According to your instructions, I copied the same patch formula but replaced Defaults with Lookup:

ForAll(
Gallery1.AllItems.Checkbox1,
Collect(
ProductsSelected,ThisRecord)
);

Patch(
PATestMaster,
Lookup(PATestMaster,Title=DataCardValue1.Text),
{
'AuthorizedCountries (AuthorizedCountriesNew)':ComboBox1.SelectedItems
};
SharePointForm1.Updates,
{
ProductIdentifier: Concat(ProductsSelected,ThisRecord.Value & " | "),
'Services Selected': ServicesDisplayed_TXT.Text
});
NewForm(SharePointForm1)

(I get multiple errors including Lookup unknown/unsupported function, Patch has invalid arguments and Name not valid/recognized (whether ID or Title)

Here is the first screen with SP list datacards: 

[FLMike]

When I look at your code you copied and pasted you spelled it Lookup its spelled LookUp

Cheers
If you like my answer, please Mark it as Resolved, and give it a thumbs up, so it can help others
Thank You
Michael Gernaey MCT | MCSE | MCP | Self-Contractor| Ex-Microsoft
https://gernaeysoftware.com
LinkedIn: https://www.linkedin.com/in/michaelgernaey

[FLMike]

Just write this and tell me what you see.

Patch(
PATestMaster,
LookUp(PATestMaster,Title=DataCardValue1.Text),
{
'AuthorizedCountries (AuthorizedCountriesNew)':ComboBox1.SelectedItems
}
);

Comment out everything in the patch button except that. Im not sure what all that other stuff is for in there. 

If you us an Edit form it works one way. If you want to do a Patch, a straight Patch it works another, so now sure what all that other stuff is you have in the button. But you need to construct a valid patch statement. Lets see what error if any you get from this.

And please copy and paste the error I would like to see it.

[acoliva]

WOW. I completely missed that. I can't believe I missed that small detail all along. I had tried LookUp previously with no success but surely it was because I did not capitalize. the U.

Thank you so much for your time and responses!