處理事件型統計資料變更

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

XblRealTimeActivitySubscriptionHandle subscriptionHandle{ nullptr };

HRESULT hr = XblUserStatisticsSubscribeToStatisticChange(
    xboxLiveContext,
    xboxUserId,
    scid,
    statisticName.c_str(),
    &subscriptionHandle
);

XblUserStatisticsRemoveStatisticChangedHandler(
        xboxLiveContext,
        statisticChangedFunctionContext
);

hr = XblUserStatisticsUnsubscribeFromStatisticChange(
    xboxLiveContext,
    statisticChangeSubscriptionHandle
);