Added in [API level 20](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Methods](https://developer.android.com/reference/android/app/Notification.Extender#pubmethods)

# Notification.Extender

*** ** * ** ***

` public static interface Notification.Extender `   
` `

|---|
| android.app.Notification.Extender |

Known indirect subclasses [Notification.CarExtender](https://developer.android.com/reference/android/app/Notification.CarExtender), [Notification.ProjectedExtender](https://developer.android.com/reference/android/app/Notification.ProjectedExtender), [Notification.TvExtender](https://developer.android.com/reference/android/app/Notification.TvExtender), [Notification.WearableExtender](https://developer.android.com/reference/android/app/Notification.WearableExtender) [Notification.CarExtender](https://developer.android.com/reference/android/app/Notification.CarExtender) Helper class to add Android Auto extensions to notifications.
[Notification.ProjectedExtender](https://developer.android.com/reference/android/app/Notification.ProjectedExtender) Helper class to add projection-specific extensions to a notification. [Notification.TvExtender](https://developer.android.com/reference/android/app/Notification.TvExtender) Helper class to add Android TV extensions to notifications.
[Notification.WearableExtender](https://developer.android.com/reference/android/app/Notification.WearableExtender) Helper class to add wearable extensions to notifications.   

*** ** * ** ***

Extender interface for use with `https://developer.android.com/reference/android/app/Notification.Builder#extend(android.app.Notification.Extender)`. Extenders may be used to add metadata or change options on a notification builder.

## Summary

| ### Public methods ||
|---|---|
| ` abstract https://developer.android.com/reference/android/app/Notification.Builder` | ` https://developer.android.com/reference/android/app/Notification.Extender#extend(android.app.Notification.Builder)(https://developer.android.com/reference/android/app/Notification.Builder builder) ` Apply this extender to a notification builder. |

## Public methods

### extend

Added in [API level 20](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public abstract Notification.Builder extend (Notification.Builder builder)
```

Apply this extender to a notification builder.

<br />

| Parameters ||
|---|---|
| `builder` | `Notification.Builder`: the builder to be modified. This value cannot be `null`. <br /> |

| Returns ||
|---|---|
| `https://developer.android.com/reference/android/app/Notification.Builder` | the build object for chaining. This value cannot be `null`. <br /> |