Invoice and Items Management Example

This example showcases a simple yet powerful use case of the Django Crispy Formset Modal package. Here, we are implementing an invoicing system where you can create an invoice and add multiple items to it dynamically using a modal formset.

The main form is used to enter the invoice details such as the invoice number, date, and client. Then, there's a formset inside a modal for managing the items related to that invoice. Each item consists of a description, quantity, and unit price.

class InvoiceItemForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.helper = ModalEditFormHelper()
        self.helper.layout = ModalEditLayout(
            "description",
            "quantity",
            "unit_price",
        )

    class Meta:
        model = InvoiceItem
        fields = "__all__"

class InvoiceForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.helper = FormHelper()
        self.helper.layout = Layout(
            Row(Column("invoice_number"), Column("date")),
            "client",
            Fieldset(
                "Items",
                ModalEditFormsetLayout(
                    "InvoiceItemInline",
                    list_display=["description", "quantity", "unit_price"],
                ),
            ),
            Submit("submit", "Save"),
        )

    class Meta:
        model = Invoice
        fields = "__all__"
        widgets = {"date": DateInput}

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