Make an interface element aware of its presence in a collection

[sloughcow]

Hi there - I'm new to PowerApps and just learned about collections. I can see how to make an interface element like a checkbox cause an item to get added to what's effectively an array, and it's really easy to cause items to be added or removed to a collection - that's joyful!

I can't quite figure out how to make that checkbox aware that ThisItem was removed from a collection - I want it to listen for the item's status in a collection, and act when the status changes.

For example...

I have a checkbox that adds an item to a collection, and I have a button that removes an item from a collection. But I could have multiple screens with different user interactions, so...

• The checkbox on screen 1 that adds the item to a collection works beautifully
• The button on screen 2 that removes the item from the collection also works beautifully
• ...but if a user adds ThisItem to the collection on screen 1 and removes ThisItem from the collection on screen 2, and navigates back to screen 1... the checkbox remains checked. I would like the checkbox to listen for ThisItem's addition or removal from that collection, and change its state as a result. 

It's possible, right? I'll appreciate advice!

[AmDev · Accepted solution]

Hi @sloughcow 

Set the Default property of your checkbox to:

ThisItem in YourCollectionName

Hope this helps

[sloughcow]

Thank you @AmDev !