openproject/frontend/app/components/wp-edit/wp-edit-field/wp-edit-date-field.directive.html

<op-date-picker
  on-change="vm.submit()"
  on-deactivate="vm.deactivate()"
  ng-model="vm.workPackage[vm.fieldName]">

  <input ng-model="vm.workPackage[vm.fieldName]"
         type="text"
         focus/>

</op-date-picker>