in this below code _invoiceInformation
in first initialize is null
and i'm trying to use dart
null safe to manage that in my flutter
applications
in this code although i used ?
operation i still get error:
Error:
RangeError (index): Index out of range: no indices are valid: 0
what i want to try:
_invoiceInformation = Hive.box<InvoiceInformation>('invoice_information');
_province.text=_invoiceInformation?.getAt(0)?.province??'';
_province.text=_invoiceInformation?.getAt(0)?.province??'';
If the list _invoiceInformation
is empty ie having zero elements, then the null aware operator ?
will allow you to access the element at 0, which is causing the error.
You will also have to check whether the list is empty or not before accessing its elements.
if(_invoiceInformation != null && _invoiceInformation.isNotEmpty) {
_province.text=_invoiceInformation.getAt(0)?.province ?? '';
}
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