Migration guide for describeEnum and EnumProperty

The global method describeEnum has been deprecated. Previous uses of describeEnum(Enum.something) should use Enum.something.name instead.

The class EnumProperty was modified to extend <T extends Enum?> instead of <T>. Existing uses of EnumProperty<NotAnEnum> should use DiagnosticsProperty<NotAnEnum> instead.

Dart 2.17 introduced enhanced enums, which added Enum as a type. As a result, all enums got a name getter, which made describeEnum redundant. Before that, enum classes were often analyzed using an EnumProperty.

The describeEnum method was used to convert an enum value to a string, since Enum.something.toString() would produce Enum.something instead of something, which a lot of users wanted. Now, the name getter does this.

The describeEnum function is being deprecated, so the EnumProperty class is updated to only accept Enum objects.

Remove describeEnum.

• Replace describeEnum(Enum.something) with Enum.something.name.

The EnumProperty now expects null or an Enum; you can no longer pass it a non-Enum class.

If you previously used describeEnum(Enum.field) to access the string value from an enum, you can now call Enum.field.name.

If you previously used EnumProperty<NotAnEnum>, you can now use the generic DiagnosticsProperty<NotAnEnum>.

Code before migration:

enum MyEnum { paper, rock }

print(describeEnum(MyEnum.paper)); // output: paper

// TextInputType is not an Enum
properties.add(EnumProperty<TextInputType>( ... ));

Code after migration:

enum MyEnum { paper, rock }

print(MyEnum.paper.name); // output: paper

// TextInputType is not an Enum
properties.add(DiagnosticsProperty<TextInputType>( ... ));

Landed in version: 3.14.0-2.0.pre
In stable release: 3.16

API documentation:

• describeEnum
• EnumProperty

Relevant issues:

• Cleanup SemanticsFlag and SemanticsAction issue

Relevant PRs:

• Deprecate describeEnum PR

除非另有说明，本文档之所提及适用于 Flutter 的最新稳定版本，本页面最后更新时间: 2024-04-04。 查看文档源码 或者 为本页面内容提出建议。