Basically I try to do a port of
GoldCcCvcInput to a dart implementation, instead of wrapping of a js implementation.
@PolymerRegister('nbdate-input') class NbdateInput extends PolymerElement with PaperInputBehavior, IronControlState, IronA11yKeysBehavior ...
Minimal test project
The project initialize without dumping any error messages and displays the iron-input elements ok. But when one of the iron-input elements are put in focus, the exception below is dumped in the console:
Uncaught TypeError: Cannot read property 'focus' of undefined Polymer.PaperInputBehaviorImpl._onFocus handler Polymer.Base._addFeature.fire Polymer.IronControlState._focusBlurHandler
This has an override of method
In dart a corresponding Observer is triggered, with a printout occurring after the exception dump.
For my case the needed functionality was provided by
With Dart following the structure of last example (Social Security Number) in
Answered By – Jonas Bojesen
Answer Checked By – Katrina (FlutterFixes Volunteer)