Programming the RTA service

// Add a statistic changed handler.
void* context{ nullptr };
XblFunctionContext statisticChangedFunctionContext = XblUserStatisticsAddStatisticChangedHandler(
    xboxLiveContext,
    [](XblStatisticChangeEventArgs eventArgs, void* context)
    {
        // Handle statistic change. 
        LogToScreen("Statistic changed callback: stat changed (%s = %s)",
            eventArgs.latestStatistic.statisticName,
            eventArgs.latestStatistic.value);
    },
    context
    );

// Configure the statistics that you want RTA to track. Titles only receive real-time updates for tracked statistics.
// Note that you can update the set of tracked statistics independently from the handlers.
std::vector<const char*> statisticNames{ "TotalPuzzlesSolved" };
HRESULT hr = XblUserStatisticsTrackStatistics(
    xblContextHandle,
    &xboxUserId,
    1,
    scid,
    statisticNames.data(),
    statisticNames.size()
);

// Stop receiving updates for a particular statistic.   
std::vector<const char*> statisticNames{ "TotalPuzzlesSolved" }; 
HRESULT hr = XblUserStatisticsStopTrackingStatistics(
    xblContextHandle,
    &xboxUserId,
    1,
    scid,
    statisticNames.data(),
    statisticNames.size()
);

// Alternatively, stop receiving updates for statistics changes altogether.
XblUserStatisticsRemoveStatisticChangedHandler(
    xblContextHandle,
    statisticChangedFunctionContext
);