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# XGameStreamingRegisterClientPropertiesChanged

> XGameStreamingRegisterClientPropertiesChanged

# XGameStreamingRegisterClientPropertiesChanged

Registers a callback to be invoked when any streaming client device's properties change.

<Note>Upon registration, the callback will be invoked for the client device's current client properties.</Note>

## Syntax

```cpp theme={null}
HRESULT XGameStreamingRegisterClientPropertiesChanged(  
         XGameStreamingClientId client,  
         XTaskQueueHandle queue,  
         void* context,  
         XGameStreamingClientPropertiesChangedCallback* callback,  
         XTaskQueueRegistrationToken* token  
)  
```

### Parameters

*client*   \_In\_\
Type: XGameStreamingClientId

ID of the game streaming client that you are registering to get callbacks for.

*queue*   \_In\_opt\_\
Type: XTaskQueueHandle

Handle to the asynchronous queue to put the change callback on.

*context*   \_In\_opt\_\
Type: void\*

An optional pointer to a context that will be passed to the callback function.

*callback*   \_In\_\
Type: [XGameStreamingClientPropertiesChangedCallback\*](/reference/system/xgamestreaming/functions/xgamestreamingclientpropertieschangedcallback)

The callback function that will be invoked when the properties of the client change.

*token*   \_Out\_\
Type: XTaskQueueRegistrationToken\*

A pointer to the registration token which can be used to unregister from the event.

### Return value

Type: HRESULT

Returns **S\_OK** if successful; otherwise, returns an error code.

#### Potential Errors

| Error Code                               | Error Value | Reason for Error                                                                                                                                                                     |
| ---------------------------------------- | ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| E\_GAMESTREAMING\_NOT\_INITIALIZED       | 0x89245400  | The XGameStreaming runtime has not been initialized. Call [XGameStreamingInitialize](/reference/system/xgamestreaming/functions/xgamestreaminginitialize) before calling other APIs. |
| E\_GAMESTREAMING\_CLIENT\_NOT\_CONNECTED | 0x89245401  | The specified client is not connected.                                                                                                                                               |

For a list of error codes, see [Error Codes](/reference/errorcodes).

## Remarks

<Note>This function isn't safe to call on a time-sensitive thread. For more information, see [Time-sensitive threads](https://learn.microsoft.com/gaming/gdk/docs/gdk-dev/console-dev/overviews/threads/time-sensitive-threads).</Note>

This API allows the game to receive a `XGameStreamingClientPropertiesChangedCallback` whenever a [XGameStreamingClientProperty](/reference/system/xgamestreaming/enums/xgamestreamingclientproperty), like stream physical dimensions, changes.

Registration **WILL** cause the callback to invoked with all applicable `XGameStreamingClientProperty`, so that querying for current property details can be done.

When the streaming client device disconnects, please use [XGameStreamingUnregisterClientPropertiesChanged](/reference/system/xgamestreaming/functions/xgamestreamingunregisterclientpropertieschanged) to unregister the callback.

## Example

```cpp theme={null}
    // On client connection maintain a list of clients and do per client initialization
    void GameStreamingClientManager::OnClientConnected(XGameStreamingClientId client)
    {
        StreamingClient connectedClient;
        connectedClient.clientId = client;
        connectedClient.propertiesChangedToken = token;

        // Do per-client initialization
        XGameStreamingClientPropertiesChangedRegistrationToken token = {0};
        XGameStreamingRegisterClientPropertiesChanged(
            client, m_taskQueue, this, &OnClientPropertiesChanged, &token);        

        connectedClient.propertiesChangedToken = token;
        m_streamingClients.push_back(connectedClient);
    }

    // Some of the properties of our streaming client have changed, react to any of the changes which apply to our game
    void GameStreamingClientManager::OnClientPropertiesChanged(
        void* context,
        XGameStreamingClientId client,
        uint32_t updatedPropertiesCount,
        XGameStreamingClientProperty* updatedProperties)
    {
        GameStreamingClientManager* gsClientManager = reinterpret_cast<GameStreamingClientManager*>(context);

        for (uint32_t i = 0; i < updatedPropertiesCount; ++i)
        {
            switch (updatedProperties[i])
            {
                // The client now has a new physical size of the game stream - update our list of stream
                // sizes to reflect this.
            case XGameStreamingClientProperty::StreamPhysicalDimensions:
                gsClientManager->UpdateClientPhysicalDimensions(client); 
                break;

            case XGameStreamingClientProperty::TouchInputEnabled: 
                gsClientManager->UpdateClientTouchEnabled(client); 
                break;

            default:
                // A characteristic we are not tracking - do nothing
                break;
            }
        }
    }

```

## Requirements

**Header:** xgamestreaming.h

**Library:** xgameruntime.lib

**Supported platforms:** Windows, XBOX One family consoles and XBOX Series consoles

## Conceptual documentation

* [Time-sensitive threads](https://learn.microsoft.com/gaming/gdk/docs/gdk-dev/console-dev/overviews/threads/time-sensitive-threads)

## See also

[XGameStreamingClientProperty](/reference/system/xgamestreaming/enums/xgamestreamingclientproperty)\
[XGameStreamingClientPropertiesChangedCallback](/reference/system/xgamestreaming/functions/xgamestreamingclientpropertieschangedcallback)\
[XGameStreamingUnregisterClientPropertiesChanged](/reference/system/xgamestreaming/functions/xgamestreamingunregisterclientpropertieschanged)\
[XGameStreaming](/reference/system/xgamestreaming/xgamestreaming_members)


## Related topics

- [XGameStreamingUnregisterClientPropertiesChanged](/reference/system/xgamestreaming/functions/xgamestreamingunregisterclientpropertieschanged.md)
- [XGameStreamingClientPropertiesChangedCallback](/reference/system/xgamestreaming/functions/xgamestreamingclientpropertieschangedcallback.md)
- [XGameStreamingClientProperty](/reference/system/xgamestreaming/enums/xgamestreamingclientproperty.md)
- [XGameStreamingIsTouchInputEnabled](/reference/system/xgamestreaming/functions/xgamestreamingistouchinputenabled.md)
- [XGameStreaming](/reference/system/xgamestreaming/xgamestreaming_members.md)