Multi Form Validation — Flutter

This blog is regarding the validation of multiple textformfields.

The demonstration had divided into two parts:

Building UI with a basic form.

Validate the fields.

Building UI with a basic form

This form contains an appbar, four textformfeilds, and a raisedbutton.

Basic UI for validation.

Validate the fields

• Declare a variable ‘_key’ as GlobalKey<FormState>, where we use this as a key for Form.
• Declare a variable ‘_autoValidate’ as boolean and assign value equals to false, where we use this to autovalidate the Form.
• Now, add the validations to each textformfield.

_validateName

_validateUserName

_validateAge

_validateBio

All these validations will be different based on textformfeild usage.

Now, we can validate the all textformfields with raisedbutton.

RaisedButton(
     color: Colors.blue,
     child: Text('Save'),
     onPressed: () {
         if(_key.currentState.validate()){
          showDialog(
          context: context,
          child: AlertDialog(
          title: Text('Validated'),
          )
        );
      }
    },
  ),

When we click the raisedbutton, if all the textformfields are not filled then it returns the validator message.

When you click save without filling the fields.

When you click the save with wrong format input in textformfield it returns the validation message as shown in below image.

When the input is in wrong format.

When we click the save with correct input, then it validates the textformfields as true and show an alertdialog as ‘Validated’.

In this way we can validate the multiple textformfields.

For GitHub Code — Click Here

If there are any suggetions for better approch to write my next blog. Please let me know!