# MediaRouteProvider.Callback

Artifact: [androidx.mediarouter:mediarouter](https://developer.android.com/jetpack/androidx/releases/mediarouter) [View Source](https://cs.android.com/search?q=file:androidx/mediarouter/media/MediaRouteProvider.java+class:androidx.mediarouter.media.MediaRouteProvider.Callback) Added in [1.1.0](https://developer.android.com/jetpack/androidx/releases/mediarouter#1.1.0)

*** ** * ** ***


```
public abstract class MediaRouteProvider.Callback
```

<br />

*** ** * ** ***

Callback which is invoked when route information becomes available or changes.

## Summary

| ### Public constructors |
|---|
| `https://developer.android.com/reference/androidx/mediarouter/media/MediaRouteProvider.Callback#Callback()()` |

| ### Public methods |
|---|---|
| `void` | `https://developer.android.com/reference/androidx/mediarouter/media/MediaRouteProvider.Callback#onDescriptorChanged(androidx.mediarouter.media.MediaRouteProvider,androidx.mediarouter.media.MediaRouteProviderDescriptor)( @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/mediarouter/media/MediaRouteProvider provider, @https://developer.android.com/reference/androidx/annotation/Nullable https://developer.android.com/reference/androidx/mediarouter/media/MediaRouteProviderDescriptor descriptor )` Called when information about a route provider and its routes change. |

## Public constructors

### Callback

Added in 1.1.0

```
public Callback()
```

## Public methods

### onDescriptorChanged

Added in [1.1.0](https://developer.android.com/jetpack/androidx/releases/mediarouter#1.1.0)

```
public void onDescriptorChanged(
    @NonNull MediaRouteProvider provider,
    @Nullable MediaRouteProviderDescriptor descriptor
)
```

Called when information about a route provider and its routes change.

| Parameters |
|---|---|
| `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/mediarouter/media/MediaRouteProvider provider` | The media route provider that changed, never null. |
| `@https://developer.android.com/reference/androidx/annotation/Nullable https://developer.android.com/reference/androidx/mediarouter/media/MediaRouteProviderDescriptor descriptor` | The new media route provider descriptor, or null if none. |