Decrementing count in collection when collection is edited

Hi all,

I have created a gallery which uses a collection as its data source, this collection is generated when the screen becomes visible as such - ClearCollect(Findings, {no:1}). I also have a button that creates additional rows in the collection - Patch(auditFindings, Defaults(Findings), {no:CountRows(Findings)+1). In the gallery, I have a field called reportnumber-00X whereby X is thisitem.no

The problem comes in when I try to delete the entry in the gallery (done through a button in the gallery with onSelect property of RemoveIf(Findings, no=thisitem.no) . I would like the field reportnumber-00X to update automatically. E.g. if i have reportnumber-001, reportnumber-002, reportnumber-003, reportnumber-004 and I delete reportnumber-002, the gallery should show reportnumber-001, reportnumber-002, reportnumber-003 instead of reportnumber-001, reportnumber-003, reportnumber-004. How can this be achieved? TIA!

Hi @ccqn ,

I have had to do something similar. This is how I achieved what you are trying to do:

1) In the OnVisible of a Screen, use:

ClearCollect(Findings, {no:1,Title:"Item1"})

2) Add a Gallery to the Screen and a "+" icon above it:

3) Set the Gallery Data Source to "Findings". Add two Labels to the Template for the Gallery and link them to the "no" value and the "Title" value.

4) For the "+" icon, set the OnSelect to:

Collect(Findings, {no:CountRows(Findings)+1, Title:"Item" & Text(CountRows(Findings)+1)})

5) In the Template for the Gallery, add a "Trash"can icon. Set the OnSelect to:

RemoveIf(
 Findings,
 no = ThisItem.no
);
ClearCollect(
 Findings,
 With(
 {records: Findings},
 ForAll(
 Sequence(CountRows(records)),
 Patch(
 Last(
 FirstN(
 records,
 Value
 )
 ),
 {no: Value}
 )
 )
 )
);

With the example, you should now be able to add and delete items. The "no" field will update. See below:

The item with the Title "Item3" was deleted and the other items renumbered.

I pulled this example together using this article:

https://powerapps.co.nz/auckland/index.php/our-blog/41-add-alternating-row-colours-to-power-apps-gallery

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Thanks.

-Mark