# showAutocorrectionPromptRect method added to TextInputClient

> A new method, void showAutocorrectionPromptRect(int start, int end), was added to the TextInputClient interface




:::important
These breaking change docs are accurate, as of the release
under which they are published. Over time, the
workarounds described here might become inaccurate.
We don't, in general, keep these breaking change docs up
to date as of each release.

The [breaking change index file](/release/breaking-changes)
lists the docs created for each release.
:::


## Summary

A new method,`void showAutocorrectionPromptRect(int start, int end)`,
was added to the `TextInputClient` interface.

## Context

In order to display the iOS autocorrection highlight,
the iOS text input plugin needed a way to inform the
Flutter framework of the highlight's start and end position.

## Description of change

A new method, `void showAutocorrectionPromptRect(int start, int end)`,
was added to the `TextInputClient` interface. iOS calls this method
when it finds a new potential autocorrect candidate
in the current user input, or when the range of a previously
highlighted candidate changes.

## Migration guide

If your application doesn't implement or subclass `TextInputClient`,
no migration is needed. If your application doesn't target iOS,
or the class that implemented the `textInputClient` interface doesn't
support autocorrect, you only need to add an empty implementation
for the new method:

```dart
class CustomTextInputClient implements TextInputClient {
  void showAutocorrectionPromptRect(int start, int end) {}
}
```

Otherwise, if your app targets iOS and supports autocorrect on iOS,
we recommend that you add a sensible implementation of
`void showAutocorrectionPromptRect(int start, int end)`
to your `TextInputClient` subclass.

Code after migration:

```dart
// Assume your `TextInputClient` is a `State` subclass, and it has a variable
// `_currentPromptRectRange` that controls the autocorrection highlight.
class CustomTextInputClient extends State<...> implements TextInputClient {
  @override
  void updateEditingValue(TextEditingValue value) {
    // When the text changes, the highlight needs to be dismissed.
    if (value.text != _value.text) {
      setState(() {
        _currentPromptRectRange = null;
      });
    }
  }

  void _handleFocusChanged() {
    // When this text input loses focus, the autocorrection highlight needs
    // to be dismissed.
    if (!_hasFocus) {
      setState(() {
        _currentPromptRectRange = null;
      });
    }
  }

  @override
  void showAutocorrectionPromptRect(int start, int end) {
    // Updates the range of the highlight, as iOS requested.
    // This method isn't called when iOS decides to
    // dismiss the highlight.
    setState(() {
      _currentPromptRectRange = TextRange(start: start, end: end);
    });
  }
}
```

## Timeline

In stable release: 1.20

## References

API documentation:

* [`TextInputClient`][]

Relevant issue:

* [Issue 12920][]

Relevant PR:

* [iOS UITextInput autocorrection prompt][]


[iOS UITextInput autocorrection prompt]: https://github.com/flutter/flutter/pull/54119/
[Issue 12920]: https://github.com/flutter/flutter/issues/12920
[`TextInputClient`]: https://api.flutter.dev/flutter/services/TextInputClient-class.html