cdf

class ModelChoiceField

from django.forms import ModelChoiceField
Documentation Source code 
A ChoiceField whose choices are a model QuerySet.

Ancestors (MRO)

  1. ModelChoiceField
  2. ChoiceField
  3. Field

Attributes

  Defined in
creation_counter = 0 Field
default_error_messages = {'invalid_choice': 'Select a valid choice. That choice is not one of the available choices.'} ModelChoiceField
default_error_messages = {'invalid_choice': 'Select a valid choice. %(value)s is not one of the available choices.'} ChoiceField
default_error_messages = {'required': 'This field is required.'} Field
default_validators = [] Field
empty_values = [None, '', [], (), {}] Field
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Properties

def choices(): ModelChoiceField

Getter

    def _get_choices(self):
        # If self._choices is set, then somebody must have manually set
        # the property self.choices. In this case, just return self._choices.
        if hasattr(self, '_choices'):
            return self._choices

        # Otherwise, execute the QuerySet in self.queryset to determine the
        # choices dynamically. Return a fresh ModelChoiceIterator that has not been
        # consumed. Note that we're instantiating a new ModelChoiceIterator *each*
        # time _get_choices() is called (and, thus, each time self.choices is
        # accessed) so that we can ensure the QuerySet has not been consumed. This
        # construct might look complicated but it allows for lazy evaluation of
        # the queryset.
        return self.iterator(self)

Setter

    def _set_choices(self, value):
        # Setting choices also sets the choices on the widget.
        # choices can be any iterable, but we call list() on it because
        # it will be consumed more than once.
        if callable(value):
            value = CallableChoiceIterator(value)
        else:
            value = list(value)

        self._choices = self.widget.choices = value

def choices(): ChoiceField

Getter

    def _get_choices(self):
        return self._choices

Setter

    def _set_choices(self, value):
        # Setting choices also sets the choices on the widget.
        # choices can be any iterable, but we call list() on it because
        # it will be consumed more than once.
        if callable(value):
            value = CallableChoiceIterator(value)
        else:
            value = list(value)

        self._choices = self.widget.choices = value

def queryset(): ModelChoiceField

Getter

    def _get_queryset(self):
        return self._queryset

Setter

    def _set_queryset(self, queryset):
        self._queryset = queryset
        self.widget.choices = self.choices
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Methods

def bound_data(self, data, initial): Field 

        Return the value that should be shown for this field on render of a
        bound form, given the submitted POST data for the field and the initial
        data, if any.

        For most fields, this will simply be data; FileFields need to handle it
        a bit differently.
        
    def bound_data(self, data, initial):
        """
        Return the value that should be shown for this field on render of a
        bound form, given the submitted POST data for the field and the initial
        data, if any.

        For most fields, this will simply be data; FileFields need to handle it
        a bit differently.
        """
        if self.disabled:
            return initial
        return data

def clean(self, value): Field 

        Validates the given value and returns its "cleaned" value as an
        appropriate Python object.

        Raises ValidationError for any errors.
        
    def clean(self, value):
        """
        Validates the given value and returns its "cleaned" value as an
        appropriate Python object.

        Raises ValidationError for any errors.
        """
        value = self.to_python(value)
        self.validate(value)
        self.run_validators(value)
        return value

def get_bound_field(self, form, field_name): Field 

        Return a BoundField instance that will be used when accessing the form
        field in a template.
        
    def get_bound_field(self, form, field_name):
        """
        Return a BoundField instance that will be used when accessing the form
        field in a template.
        """
        return BoundField(form, self, field_name)

def get_limit_choices_to(self): ModelChoiceField 

        Returns ``limit_choices_to`` for this form field.

        If it is a callable, it will be invoked and the result will be
        returned.
        
    def get_limit_choices_to(self):
        """
        Returns ``limit_choices_to`` for this form field.

        If it is a callable, it will be invoked and the result will be
        returned.
        """
        if callable(self.limit_choices_to):
            return self.limit_choices_to()
        return self.limit_choices_to

def has_changed(self, initial, data):

ModelChoiceField

    def has_changed(self, initial, data):
        if self.disabled:
            return False
        initial_value = initial if initial is not None else ''
        data_value = data if data is not None else ''
        return force_text(self.prepare_value(initial_value)) != force_text(data_value)

Field

        Return True if data differs from initial.
        
    def has_changed(self, initial, data):
        """
        Return True if data differs from initial.
        """
        # Always return False if the field is disabled since self.bound_data
        # always uses the initial value in this case.
        if self.disabled:
            return False
        try:
            data = self.to_python(data)
            if hasattr(self, '_coerce'):
                return self._coerce(data) != self._coerce(initial)
        except ValidationError:
            return True
        # For purposes of seeing whether something has changed, None is
        # the same as an empty string, if the data or initial value we get
        # is None, replace it with ''.
        initial_value = initial if initial is not None else ''
        data_value = data if data is not None else ''
        return initial_value != data_value

def label_from_instance(self, obj): ModelChoiceField 

        This method is used to convert objects into strings; it's used to
        generate the labels for the choices presented by this object. Subclasses
        can override this method to customize the display of the choices.
        
    def label_from_instance(self, obj):
        """
        This method is used to convert objects into strings; it's used to
        generate the labels for the choices presented by this object. Subclasses
        can override this method to customize the display of the choices.
        """
        return force_text(obj)

def prepare_value(self, value):

ModelChoiceField

    def prepare_value(self, value):
        if hasattr(value, '_meta'):
            if self.to_field_name:
                return value.serializable_value(self.to_field_name)
            else:
                return value.pk
        return super(ModelChoiceField, self).prepare_value(value)

Field

    def prepare_value(self, value):
        return value

def run_validators(self, value): Field 

    def run_validators(self, value):
        if value in self.empty_values:
            return
        errors = []
        for v in self.validators:
            try:
                v(value)
            except ValidationError as e:
                if hasattr(e, 'code') and e.code in self.error_messages:
                    e.message = self.error_messages[e.code]
                errors.extend(e.error_list)
        if errors:
            raise ValidationError(errors)

def to_python(self, value):

ModelChoiceField

    def to_python(self, value):
        if value in self.empty_values:
            return None
        try:
            key = self.to_field_name or 'pk'
            value = self.queryset.get(**{key: value})
        except (ValueError, TypeError, self.queryset.model.DoesNotExist):
            raise ValidationError(self.error_messages['invalid_choice'], code='invalid_choice')
        return value

ChoiceField

Returns a Unicode object.
    def to_python(self, value):
        "Returns a Unicode object."
        if value in self.empty_values:
            return ''
        return force_text(value)

Field

    def to_python(self, value):
        return value

def valid_value(self, value): ChoiceField 

Check to see if the provided value is a valid choice
    def valid_value(self, value):
        "Check to see if the provided value is a valid choice"
        text_value = force_text(value)
        for k, v in self.choices:
            if isinstance(v, (list, tuple)):
                # This is an optgroup, so look inside the group for options
                for k2, v2 in v:
                    if value == k2 or text_value == force_text(k2):
                        return True
            else:
                if value == k or text_value == force_text(k):
                    return True
        return False

def validate(self, value):

ModelChoiceField

    def validate(self, value):
        return Field.validate(self, value)

ChoiceField

        Validates that the input is in self.choices.
        
    def validate(self, value):
        """
        Validates that the input is in self.choices.
        """
        super(ChoiceField, self).validate(value)
        if value and not self.valid_value(value):
            raise ValidationError(
                self.error_messages['invalid_choice'],
                code='invalid_choice',
                params={'value': value},
            )

Field

    def validate(self, value):
        if value in self.empty_values and self.required:
            raise ValidationError(self.error_messages['required'], code='required')

def widget_attrs(self, widget): Field 

        Given a Widget instance (*not* a Widget class), returns a dictionary of
        any HTML attributes that should be added to the Widget, based on this
        Field.
        
    def widget_attrs(self, widget):
        """
        Given a Widget instance (*not* a Widget class), returns a dictionary of
        any HTML attributes that should be added to the Widget, based on this
        Field.
        """
        return {}