SetFocus on unfilled fields in form

I would like to use SetFocus on a control that isn’t filled out (i.e. Text Input) in my form when the submit button is clicked. The simplest way is to manually check all the controls and focus on the first one that isn’t filled out.

If(IsBlank(TextInput1.Text), SetFocus(TextInput1));
If(IsBlank(TextInput2.Text), SetFocus(TextInput2));
...

Here’s the kicker though, there are 144 possible fields to be inputted. This would be extremely tedious to grab the names of each control and check every single field manually, which is why I’m trying to avoid doing it this way.

The following is what I’ve looked into.

The ForAll function only accepts records and if I convert the form to a record, it converts all of the controls into record types. I need it to stay as a control type so I can use the SetFocus function.
I’ve also discovered that the Parent Child relationship in PowerApps is very limited. I can only go one Parent up, refer to the object itself using “This”, and can’t go one layer down (no "Child" or "Children" properties).
I've tried converting the control into a collection but again, it converts the controls into a non-control type.

Is there any way to accomplish what I want to do, without checking every single field manually?

Solution

Unfortunately there is no way to do that in a simpler way today. In theory we could have something like the following:

With(
  { firstEmpty:LookUp([TextInput1, TextInput2, TextInput3, ...], IsBlank(Value.Text)) },
  If(Not IsBlank(firstEmpty), SetFocus(Value))
)

But there are a few problems with it:

You still would need to enter all of the control names in the expression
It will only work if all of the fields are of the same type (i.e., all text inputs; a date picker won't work there)
Even if all controls were of the same type, the SetFocus function today doesn't work with an argument that isn't a control itself (like in the example above, where it is a local variable declared within the With function). I don't see why this wouldn't work, so this is probably a bug

In this case I think the best option is what you have. You can also create a feature request (to access children of a form, and make the SetFocus work on this scenario) in https://aka.ms/powerapps-ideas