How to validate only dropdown search field?

[ffd114]

I run into issue where I need to validate only the dropdown search field, usually when using TextFormField I can just set the key with GlobalKey<FormFieldState>(), but I cannot find the way to do this on dropdown search, is there a way to to validate only the drop down search field?

[salim-lachdhaf]

yes, in the same way as the TextFormField .
just add a key to your DropdownSearch like :

final myKey = GlobalKey<DropdownSearchState<T>>();

DropdownSearch<T>(
     key: myKey  ,
     ...
)

then call
myKey.currentState?.validate()

[ffd114]

But DropdownSearchState does not have validate() function, so it throws error on me. Anyway for now I just forked this package and add some access to inner FormField key, even though it is not very clean but for now it's sufficient.

Thanks for this awesome package!

[salim-lachdhaf]

Yes, you are right. you can only change validationMode.
But why did not put your DropdownSearch inside a Form and call validate on form that contains your DropdownSearch ?

[ffd114]

In my use case, I use DropdownSearch to list foreign currencies, below the DropdownSearch there are text field to fill the exchange rate and a button to fetch the exchange rate from my server. When I click this button, I need to validate only the selected currency from DropdownSearch, if it is valid, it will call the API and the text field will be filled with the data from my server. If I use form valid, it will also check another field unrelated for my API calls

[salim-lachdhaf]

no, i meant you create a Form only for DropdownSearch Which will give you a structure like this

Form
--TextFormField1
--TextFormField2
--TextFormField..
--Form <--- to validate only your `DropdownSearch`
----DropdownSearch
--TextFormFieldx
...

[ffd114]

Ahh sorry I misunderstood your question, I haven't tried it that way and did not know if that will works. Thanks for the insight!

But for now even if it works, I think I will stick with the current implementation, since I still need to access the DropdownSearchState key and by using Form key I need to declare another key