XUserRegisterForChangeEvent

Registers a callback for a user change event.

Syntax

HRESULT XUserRegisterForChangeEvent(  
         XTaskQueueHandle queue,  
         void* context,  
         XUserChangeEventCallback* callback,  
         XTaskQueueRegistrationToken* token  
)  

Parameters

queue   _In_opt_
Type: XTaskQueueHandle

A handle to the asynchronous queue to perform the operation on.

context   _In_opt_
Type: void*

User defined context to pass to the callback.

callback   _In_
Type: XUserChangeEventCallback*

User defined callback to register.

token   _Out_
Type: XTaskQueueRegistrationToken*

Contains a token identifying the registered callback. Use the token to un-register the callback.

Return value

Type: HRESULT

HRESULT success or error code.
For a list of error codes, see Error Codes.

Remarks

Note

This function isn't safe to call on a time-sensitive thread. For more information, see Time-sensitive threads.

The XUserChangeEvent enumeration specifies a change event type. XUserChangeEventCallback is a callback for a user change event.

To unregister a previously registered user change callback, call XUserUnregisterForChangeEvent.

The following example demonstrates how to handle user change events.

HRESULT RegisterForChanges()
{
    RETURN_HR_IF(E_UNEXPECTED, _token.token != 0);
    RETURN_IF_FAILED(XUserRegisterForChangeEvent(
        _queue,
        this,
        UserChangeEventHandler,
        &_token));
    return S_OK;
}

void UnregisterForChanges()
{
    XUserUnregisterForChangeEvent(_token, false);
    _token.token = 0;
}

void UserChangeEventHandler(
    XUserLocalId userLocalId,
    XUserChangeEvent event)
{
    auto iter = std::find_if(
        _users.begin(),
        _users.end(),
        [&userLocalId](const User& candidate)
    {
        XUserLocalId candidateUserLocalId;
        XUserGetLocalId(candidate.Handle(), &candidateUserLocalId);
        return candidateUserLocalId == userLocalId;
    });

    // User not known
    if (iter == _users.end())
    {
        return;
    }

    auto handle = iter->Handle();

    // If a guest gets signed out, immediately close the handle
    bool isGuest;
    if (SUCCEEDED_LOG(XUserGetIsGuest(handle, &isGuest)) &&
        isGuest &&
        event == XUserChangeEvent::SignedOut)
    {
        _users.erase(iter);
    }

    if (event == XUserChangeEvent::SigningOut)
    {
        // Delay the user signing out just for fun
        XUserSignOutDeferralHandle deferral;
        if (SUCCEEDED_LOG(XUserGetSignOutDeferral(&deferral)))
        {
            // Hold the deferral for 5 seconds then close it
            std::thread completeDeferralThread(
                [deferral]()
            {
                std::this_thread::sleep_for(std::chrono::milliseconds(5000));
                XUserCloseSignOutDeferralHandle(deferral);
            });

            completeDeferralThread.detach();
        }
    }

    if (event == XUserChangeEvent::GamerPicture)
    {
        iter->LoadGamerPicAsync(_queue);
    }
}

Requirements

Header: XUser.h

Library: xgameruntime.lib

Supported platforms: Windows, Xbox One family consoles and Xbox Series consoles

See also

XUser

XUserChangeEvent

XUserChangeEventCallback

XUserUnregisterForChangeEvent