I have a series of form fields (UITextField) that have as their "Done" action (which I changed to "Next") the ability to set the firstResponder to the next field down the line, such that when a user is filling out the field they can click next to keep progressing:
fields[i-1].addTarget(fields[i], action: "becomeFirstResponder", forControlEvents: UIControlEvents.EditingDidEndOnExit)
The date picker emits
.ValueChanged when the user rotates a wheel. So hook that to whatever you hooked that text field's
.EditingDidEndOnExit to. Or hook it to something else. But the point is that you can respond directly to the date picker being changed.