MeasureRules.ApproximateValues Property

Gets or sets a value indicating whether or not it's necessary to approximate values for measure rules.

Namespace: DevExpress.XtraMap

Assembly: DevExpress.XtraMap.v20.1.dll

Declaration

[DefaultValue(false)]
public bool ApproximateValues { get; set; }
<DefaultValue(False)>
Public Property ApproximateValues As Boolean

Property Value

Type Default Description
Boolean

false

true, to approximate values; otherwise, false.

Examples

This example demonstrates how to generate bubble charts for a map control. Do the following:

    // Specify data for the bubble layer.
    BubbleLayer.Data = CreateData();
private IMapDataAdapter CreateData() {
    BubbleChartDataAdapter adapter = new BubbleChartDataAdapter() {
        DataSource = LoadData(),
        MeasureRules = CreateMeasureRules(),
        ItemMaxSize = 60,
        ItemMinSize = 10
    };

    #region #Mappings
    // Map the properties of chart items to the appropriate fields in the data source.
    adapter.Mappings.Latitude = "glat";
    adapter.Mappings.Longitude = "glon";
    adapter.Mappings.Value = "mag";
    #endregion #Mappings

    // Create attribute mappings to provide additional information about map items to the map.
    adapter.AttributeMappings.Add(new MapItemAttributeMapping("Magnitude", "mag"));
    adapter.AttributeMappings.Add(new MapItemAttributeMapping("Year", "yr"));
    adapter.AttributeMappings.Add(new MapItemAttributeMapping("Month", "mon"));
    adapter.AttributeMappings.Add(new MapItemAttributeMapping("Day", "day"));
    adapter.AttributeMappings.Add(new MapItemAttributeMapping("Depth", "dep"));

    return adapter;
}

private DataTable LoadData() {
    DataSet ds = new DataSet();
    ds.ReadXml(dataPath);
    DataTable dt = ds.Tables[0];
    dt.DefaultView.RowFilter = string.Format(CultureInfo.InvariantCulture, "(mag >= {0}) AND (mag <= {1})", minMagnitude, maxMagnitude);

    return ds.Tables[0];
}

private MeasureRules CreateMeasureRules() {
    MeasureRules measureRules = new MeasureRules();

    measureRules.ApproximateValues = true;
    measureRules.RangeDistribution = new LinearRangeDistribution();

    for (int i = minMagnitude; i < maxMagnitude; i++) {
        measureRules.RangeStops.Add(i);
    }

    return measureRules;
}

Implements

DevExpress.Map.Native.IMeasureRules.ApproximateValues
See Also