views:

21

answers:

1

I have a form that looks similar to the following (simplified for brevity):

PRICING_PATTERN = r'(?:^\$?(?P<flat_price>\d+|\d?\.\d\d)$)|(?:^(?P<percent_off>\d+)\s*\%\s*off$)'
class ItemForm(forms.Form):
    pricing = forms.RegexField(
        label='Pricing',
        regex=PRICING_PATTERN
    )

    pricing_type = forms.CharField(
        label='Deal type',
        widget=forms.RadioSelect(
            choices=(
                ('flat_price','Flat price'),
                ('percent_off','Percentage off'),
            ),
           attrs={'style': 'display: none;'})
        ),
    )

    pricing_flat_price = forms.DecimalField(
        label='Flat price',
        max_digits=5,
        decimal_places=2,
        widget=forms.TextInput(attrs={'style': 'display: none;'})
    )

    pricing_percent_off = forms.IntegerField(
        label='Percent off',
        required=False,
        min_value=0,
        max_value=100,
        widget=forms.TextInput(attrs={'style': 'display: none;'})
    )

Initially, for the purpose of graceful degradation, only pricing is visible. If the user has javascript enabled, I hide pricing and make pricing_type visible. Now, on a pricing_type radio selection, I make either pricing_flat_cost or pricing_percent_off visible. This makes for a more precise and user-friendly UI.

My questions: How should I go about coding the logic that figures out where to take the values from---the RegexField or the pricing_flat_price and pricing_percent_off fields? Should I perhaps create a function in ItemForm that figures it out and returns the correct value?

Or perhaps there's a cleaner approach that someone could suggest?

A: 

Define a custom widget for the type selection and include the JavaScript code as a separate .js file.

Ignacio Vazquez-Abrams