Added in [API level 27](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary:

# Transformation

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` public interface Transformation `   
` `

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| android.service.autofill.Transformation |

Known indirect subclasses [CharSequenceTransformation](https://developer.android.com/reference/android/service/autofill/CharSequenceTransformation), [DateTransformation](https://developer.android.com/reference/android/service/autofill/DateTransformation), [ImageTransformation](https://developer.android.com/reference/android/service/autofill/ImageTransformation) [CharSequenceTransformation](https://developer.android.com/reference/android/service/autofill/CharSequenceTransformation) Replaces a `https://developer.android.com/reference/android/widget/TextView` child of a `https://developer.android.com/reference/android/service/autofill/CustomDescription` with the contents of one or more regular expressions (regexs). [DateTransformation](https://developer.android.com/reference/android/service/autofill/DateTransformation) Replaces a `https://developer.android.com/reference/android/widget/TextView` child of a `https://developer.android.com/reference/android/service/autofill/CustomDescription` with the contents of a field that is expected to have a `https://developer.android.com/reference/android/view/autofill/AutofillValue#forDate(long)`. [ImageTransformation](https://developer.android.com/reference/android/service/autofill/ImageTransformation) Replaces the content of a child `https://developer.android.com/reference/android/widget/ImageView` of a `https://developer.android.com/reference/android/widget/RemoteViews` with the first image that matches a regular expression (regex).   

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Helper class used to change a child view of a `https://developer.android.com/reference/android/widget/RemoteViews` at runtime, using the values of fields contained in the screen.

Typically used by `https://developer.android.com/reference/android/service/autofill/CustomDescription` to provide a customized autofill save UI.

**Note:** This interface is not meant to be implemented by app developers; only implementations provided by the Android System can be used in other Autofill APIs.