The previous auto validation API for theForm andFormField widgets didn't control when auto validation should occur. So the auto validation for these widgets always happened on first build when the widget was first visible to the user, and you weren't able to control when the auto validation should happen.

Due to the original API not allowing developers to change the auto validation behavior for validating only when the user interacts with the form field, we added new API that allows developers to configure how they want auto validation to behave for theForm andFormField widgets.

The following changes were made:

• Theautovalidate parameter is deprecated.
• A new parameter calledautovalidateMode, an Enum that accepts values from theAutovalidateMode Enum class, is added.

To migrate to the new auto validation API you need to replace the usage of the deprecatedautovalidate parameter to the newautovalidateMode parameter. If you want the same behavior as before you can use:autovalidateMode = AutovalidateMode.always. This makes yourForm andFormField widgets auto validate on first build and every time it changes.

Code before migration:

classMyWidgetextendsStatelessWidget{@overrideWidgetbuild(BuildContextcontext){returnFormField(autovalidate:true,builder:(FormFieldStatestate){returnContainer();},);}}

Code after migration:

classMyWidgetextendsStatelessWidget{@overrideWidgetbuild(BuildContextcontext){returnFormField(autovalidateMode:AutovalidateMode.always,builder:(FormFieldStatestate){returnContainer();},);}}

Landed in version: 1.21.0-5.0.pre
In stable release: 1.22

API documentation:

• AutovalidateMode

Relevant issues:

• Issue 56363
• Issue 18885
• Issue 15404
• Issue 36154
• Issue 48876

Relevant PRs:

• PR 56365: FormField should autovalidate only if its content was changed
• PR 59766: FormField should autovalidate only if its content was changed (fixed)