Applying Row Number to Gallery Items

Creating a row number sequence within a Power Apps gallery is a powerful technique. It ensures consistent numbering even when items are dynamically added or removed. Let’s dive into the details:

1. Set Up Your Data Source:

Before creating the gallery, ensure you have a data source (such as a SharePoint list, Excel table, or custom collection) that contains the items you want to display. Each item should have a unique identifier (e.g., an “ID” field).

2. Create a Custom Collection for Numbering:

We’ll create a custom collection to store the numbered items. Here’s how:

1. Set the screen’s OnVisible property:

Clear(colNumberedItems); // colNumberedItems is a custom collection 

ForAll(yourDataSource,

       Collect(colNumberedItems,
               Last(FirstN(AddColumns(yourDataSource, "RowNumber", CountRows(colNumberedItems) + 1),
                            CountRows(colNumberedItems) + 1)
               )
       )
)

Replace yourDataSource with the name of your data source.

3. Design Your Gallery:
Create a gallery and bind it to colNumberedItems. Inside the gallery, add a label control to display the row number. Set the label’s Text property as follows:

LookUp(colNumberedItems, ID = ThisItem.ID).RowNumber
Replace ID with your data source’s unique identifier.



4. Test and Preview:
Save, publish, and preview your app. Now, when you add or delete items from the gallery, the numbering will adjust automatically.



5. Optional: User-Defined Sequence:
If you want users to input a specific sequence, consider using a text input control. For example:
Items = ForAll(Sequence(Value(txtEnterNumber.Text)), Blank())
Here, txtEnterNumber is a text input control where users can specify the desired sequence.
Remember to adapt these steps to your specific use case and data source. Happy app building!