Field format and field type are not the same thing. You can use data formatting in the Inspector to control how the date is displayed (but not how it is entered.)
And a lot of text fields using conditional formatting have to be entered manually,
What exactly is the issue there and how will you use a custom field type to solve that issue? (Exactly what are you "entering manually"?) (Note that if you select 5 fields while in layout mode first, you can apply the same conditional format to all of them by specifying a single such conditional format expression and color in the conditional format dialog.)
All my date fields use dd-mm-yy as format (which is not one of the predefined formats), their width is 90 points and they use a dropdown calendar with the little arrow to show and hide that calendar. I have lots of layouts with date fields. If I have to add 5 fields it is fine to format them at the same time. But I still have to remember my exact formatting guidelines each time (or look them up). And if I add a 6th field later on, I can start over.
Worse, if I decide to change the default data format to dd-mm-yyyy, I have to go back to each layout and find the date fields in them. This is tedious and error prone. It's like custom functions. We don't really need them. We could just type them out each time. :-)
I don't think I'd call that a custom field type, but being able to define specific data format settings and incorporating them as part of a layout's theme would be a useful new feature...
It's like custom functions. We don't really need them. We could just type them out each time.
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