updated combobox widget to set proper data-default-value and set domain suborganization form to use new combobox widget

src/registrar/forms/domain.py

@@ -4,6 +4,7 @@ import logging
 from django import forms
 from django.core.validators import MinValueValidator, MaxValueValidator, RegexValidator, MaxLengthValidator
 from django.forms import formset_factory
+from registrar.forms.utility.combobox import ComboboxWidget
 from registrar.models import DomainRequest, FederalAgency
 from phonenumber_field.widgets import RegionalPhoneNumberWidget
 from registrar.models.suborganization import Suborganization
@@ -161,9 +162,10 @@ class DomainSuborganizationForm(forms.ModelForm):
     """Form for updating the suborganization"""
 
     sub_organization = forms.ModelChoiceField(
+        label = "Suborganization name",
         queryset=Suborganization.objects.none(),
         required=False,
-        widget=forms.Select(),
+        widget=ComboboxWidget,
     )
 
     class Meta:
@@ -178,20 +180,6 @@ class DomainSuborganizationForm(forms.ModelForm):
         portfolio = self.instance.portfolio if self.instance else None
         self.fields["sub_organization"].queryset = Suborganization.objects.filter(portfolio=portfolio)
 
-        # Set initial value
-        if self.instance and self.instance.sub_organization:
-            self.fields["sub_organization"].initial = self.instance.sub_organization
-
-        # Set custom form label
-        self.fields["sub_organization"].label = "Suborganization name"
-
-        # Use the combobox rather than the regular select widget
-        self.fields["sub_organization"].widget.template_name = "django/forms/widgets/combobox.html"
-
-        # Set data-default-value attribute
-        if self.instance and self.instance.sub_organization:
-            self.fields["sub_organization"].widget.attrs["data-default-value"] = self.instance.sub_organization.pk
-
 
 class BaseNameserverFormset(forms.BaseFormSet):
     def clean(self):

src/registrar/forms/domain_request_wizard.py

@@ -298,23 +298,6 @@ class OrganizationContactForm(RegistrarForm):
         label="Urbanization (required for Puerto Rico only)",
     )
 
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-
-        # Initialize federal_agency combobox widget
-        # Domain requests forms have prefix associated with step
-        prefix = kwargs.get("prefix", "")
-        prefixed_name = f"{prefix}-federal_agency" if prefix else "federal_agency"
-
-        # For combobox widget, need to set the data-default-value to selected value
-        if self.is_bound and self.data.get(prefixed_name):
-            # If form is bound (from a POST), use submitted value
-            self.fields["federal_agency"].widget.attrs["data-default-value"] = self.data.get(prefixed_name)
-        elif self.domain_request and self.domain_request.federal_agency:
-            # If form is not bound, set initial
-            self.fields["federal_agency"].initial = self.domain_request.federal_agency
-            self.fields["federal_agency"].widget.attrs["data-default-value"] = self.domain_request.federal_agency.pk
-
     def clean_federal_agency(self):
         """Require something to be selected when this is a federal agency."""
         federal_agency = self.cleaned_data.get("federal_agency", None)

src/registrar/templates/django/forms/widgets/combobox.html

@@ -11,6 +11,7 @@ for now we just carry the attribute to both the parent element and the select.
         {{ name }}="{{ value }}"
     {% endif %}
 {% endfor %}
+data-default-value="{% for group_name, group_choices, group_index in widget.optgroups %}{% for option in group_choices %}{% if option.selected %}{{ option.value }}{% endif %}{% endfor %}{% endfor %}"
 >
     {% include "django/forms/widgets/select.html" %}
 </div>