Sync subscription to ReactiveCommand that subscribes to accelerometer readings and displays them.

diplay accelerometer readings

// enable the scenario when enable is executed
from(observable(enable))
    .where([this](RoutedEventPattern)
    {
        return accelerometer != nullptr;
    })
    .select_many([=](RoutedEventPattern)
    {
        return from(visible)
            .select_many([=](bool)
            {
                // enable sensor input 
                return rx::from(readingChanged)
                    .take_until(invisible);
            })
            .take_until(endScenario); // this is a subscription to the disable ReactiveCommand
    })
    .subscribe([this](AccelerometerReading^ reading)
    {
        // on the ui thread
        this->ScenarioOutput_X->Text = reading->AccelerationX.ToString();
        this->ScenarioOutput_Y->Text = reading->AccelerationY.ToString();
        this->ScenarioOutput_Z->Text = reading->AccelerationZ.ToString();
    });