Hi @Anonymous ,
On Click on Button, you are setting the variable that is fine.
I am not sure how to are doing and what is your business requirements,
On gallery is not possible this variable to Update .
So you can use below approach ,
Step 1 : Select the Screen and Set the OnVisible Properties Like below.
ClearCollect(GalColl,AddColumns(ApproverList,"IsApproved",false))

Step 2: Now Set the Icon Visible Property Like below.

Step 3 . Now to Add the Patch Code to Update The Collection.
Patch(GalColl,ThisItem,{IsApproved:true});

Note - Use this Collection as Data source in Gallery Like Below -

Thanks,
Vijay
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