/// <summary>
/// Event handler for user request to plot data based on sensor # and time constraints.
/// </summary>
/// <param name="sender">Instance of object raising event.</param>
/// <param name="e">Generic event args.</param>
private void buttonChart_Click(object sender, EventArgs e)
{
TemperatureSensor temperatureSensor = GetSelectedTemperatureSensor();
//UI Selection Validations.
if (dateTimePickerStop.Value < dateTimePickerStart.Value)
{
MessageBox.Show("Time selection for stop cannot be less than start time.",
"Invalid Time Selections",
MessageBoxButtons.OK,
MessageBoxIcon.Error);
return;
}
//Attempt to query data.
if (temperatureSensor != null)
{
//Convert timestamps to UTC for MooseBox query.
DateTime startTimeUTC = dateTimePickerStart.Value.ToUniversalTime();
DateTime stopTimeUTC = dateTimePickerStop.Value.ToUniversalTime();
//Query temperature readings within selected range.
List <Tuple <DateTime, Single> > readings = AsyncHelper.RunSync(() => { return(temperatureSensor.QueryHistoricalReadings(startTimeUTC, stopTimeUTC)); });
//Clear the graph so we don't get stale date on redraws.
Debug.Assert(chartTemperatureHistory.Series.Count > 0);
chartTemperatureHistory.Series[0].Points.Clear();
//Re-populate the chart with this batch of historical data.
Single minFahrenheit = Single.MaxValue;
Single maxFahrenheit = Single.MinValue;
foreach (var reading in readings)
{
Single fahrenheit = ConvertUnits.Temperature.CelsiusToFahrenheit(reading.Item2);
DateTime localTimestamp = reading.Item1.ToLocalTime();
//Add plot point.
chartTemperatureHistory.Series[0].Points.AddXY(localTimestamp, fahrenheit);
//Update minimum value.
if (fahrenheit < minFahrenheit)
{
minFahrenheit = fahrenheit;
}
//Update maximum value.
if (fahrenheit > maxFahrenheit)
{
maxFahrenheit = fahrenheit;
}
}
//Update the bounds/scaling so it looks better.
chartTemperatureHistory.ChartAreas[0].AxisY.Minimum = minFahrenheit - TempPlotPadding;
chartTemperatureHistory.ChartAreas[0].AxisY.Maximum = maxFahrenheit + TempPlotPadding;
//Redraw the graph.
chartTemperatureHistory.Update();
}
}
