The best way is to patch your collection using a record from that collection, and using multiple forms to gather the data that you want to patch
So let's say that
1. You have a collection: colYourCollection which is shown in a gallery
2. You've setup up 2 forms to contain the information that you want to edit (Form1 and Form2) and these forms are on two screens (Screen_Form1 and Screen_Form2 respetively)
For Form1 and Form 2 you'll need to set
Datasource = colYourCollection
Item = varRecordFromYourCollection
In your gallery add in a button and in the onSelect run the following code
ResetForm(Form1);
ResetForm(Form2);
Set(varRecordFromYourCollection, ThisItem);
Set(Form1, FormMode.Edit);
Navigate(Screen_Form1,ScreenTransition.Fade);
When you navigate to Screen_Form1 you have a button that navigates to Screen_Form2
Navigate(Screen_Form2,ScreenTransition.Fade);
And then finally on Screen_Form2 you have a save button that adds in the edits from Form 1 and Form 2 - and shows if the operation was successful or not.
Patch(colYourCollection, varRecordFromYourCollection, Form1.Updates, Form2.Updates);
If(IsEmpty(Errors(colYourCollection)),
// If no errors
Notify("Success", NotificationType.Success);
Navigate(Screen_StartingScreen),
//If we have errors
Notify(First(Errors(colYourCollection)).Message, NotificationType.Error)
);
You can add in more than 2 forms of course, and there are other things you can do as part of this flow to make it all run together better, but this is the best way IMHO.
