BubbleMapDashboardItem.ColorScale Property

Gets or sets the scale that defines the distribution of colors in the color range.

Namespace: DevExpress.DashboardCommon

Assembly: DevExpress.Dashboard.v19.1.Core.dll

Declaration

C#

[DefaultValue(null)]
public MapScale ColorScale { get; set; }

VB.NET

<DefaultValue(Nothing)>
Public Property ColorScale As MapScale

Property Value

Type	Default	Description
MapScale	*null*	A MapScale descendant specifying the scale that defines distribution of colors in the color range.

Remarks

Use the BubbleMapDashboardItem.ColorPalette property to specify the palette used to color bubbles on the map.

Example

The following example demonstrates how to bind a Bubble Map dashboard item to data in code and customize its palette.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-bind-a-bubble-map-dashboard-item-to-data-and-customize-its-palette-t119682.

Form1.cs

using System;
using System.Collections.Generic;
using DevExpress.DashboardCommon;
using DevExpress.DataAccess.ConnectionParameters;
using DevExpress.DataAccess.Sql;
using DevExpress.XtraEditors;

namespace Dashboard_CreateBubbleMap {
    public partial class Form1 : XtraForm {
        public Form1() {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e) {
            // Creates a new dashboard and a data source for this dashboard.
            Dashboard dashboard = new Dashboard();
            DashboardSqlDataSource dataSource = new DashboardSqlDataSource(); 
            dataSource.ConnectionParameters =
                new XmlFileConnectionParameters(@"..\..\Data\DashboardEnergyStatictics.xml");
            SelectQuery sqlQuery = SelectQueryFluentBuilder
                .AddTable("Countries")
                .SelectColumns("Latitude", "Longitude", "Production", "Import", "Country")
                .Build("Countries");

            dataSource.Queries.Add(sqlQuery);
            dashboard.DataSources.Add(dataSource);

            // Creates a Bubble Map dashboard item and specifies its data source.
            BubbleMapDashboardItem bubbleMap = new BubbleMapDashboardItem();
            bubbleMap.DataSource = dashboard.DataSources[0];
            bubbleMap.DataMember = "Countries";

            // Loads the map of the world.
            bubbleMap.Area = ShapefileArea.Europe;

            // Provides cities' coordinates.
            bubbleMap.Latitude = new Dimension("Latitude");
            bubbleMap.Longitude = new Dimension("Longitude");

            // Specifies measures used to evaluate bubble weights and colors.
            bubbleMap.Weight = new Measure("Production", SummaryType.Sum);
            bubbleMap.Color = new Measure("Import", SummaryType.Sum); 
            bubbleMap.Color.NumericFormat.FormatType = DataItemNumericFormatType.General;

            // Provides additional values displayed within bubble tooltips.
            bubbleMap.TooltipDimensions.Add(new Dimension("Country"));

            // Specifies a custom scale and shows map legends.
            CustomizeScale(bubbleMap);
            ShowLegends(bubbleMap);

            // Adds the Bubble Map dashboard item to the dashboard and opens this
            // dashboard in the Dashboard Viewer.
            dashboard.Items.Add(bubbleMap);
            dashboardViewer1.Dashboard = dashboard;
        }

        private void CustomizeScale(BubbleMapDashboardItem map) {
            CustomScale customScale = new CustomScale();
            List<double> rangeStops = new List<double>();

            // Specifies that the absolute scale is used to define a set of range stops.
            customScale.IsPercent = false;

            // Specifies custom range stops.   
            rangeStops.Add(20);
            rangeStops.Add(200);
            rangeStops.Add(500);
            rangeStops.Add(2000);            

            // Adds custom range stops to a custom scale.  
            customScale.RangeStops.AddRange(rangeStops);

            map.ColorScale = customScale;
        }

        private void ShowLegends(BubbleMapDashboardItem map) {
            // Enables map legends and specifies its position and orientation.
            map.Legend.Visible = true;
            map.Legend.Orientation = MapLegendOrientation.Horizontal;
            map.WeightedLegend.Visible = true;
            map.WeightedLegend.Position = MapLegendPosition.BottomLeft;
        }
    }
}

Form1.vb

Imports System
Imports System.Collections.Generic
Imports DevExpress.DashboardCommon
Imports DevExpress.DataAccess.ConnectionParameters
Imports DevExpress.DataAccess.Sql
Imports DevExpress.XtraEditors

Namespace Dashboard_CreateBubbleMap
    Partial Public Class Form1
        Inherits XtraForm

        Public Sub New()
            InitializeComponent()
        End Sub

        Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
            ' Creates a new dashboard and a data source for this dashboard.
            Dim dashboard As New Dashboard()
            Dim dataSource As New DashboardSqlDataSource()
            dataSource.ConnectionParameters =
                New XmlFileConnectionParameters("..\..\Data\DashboardEnergyStatictics.xml")
            Dim sqlQuery As SelectQuery = SelectQueryFluentBuilder.AddTable("Countries") _
                                          .SelectColumns("Latitude", "Longitude", "Production", "Import", "Country") _
                                          .Build("Countries")

            dataSource.Queries.Add(sqlQuery)
            dashboard.DataSources.Add(dataSource)

            ' Creates a Bubble Map dashboard item and specifies its data source.
            Dim bubbleMap As New BubbleMapDashboardItem()
            bubbleMap.DataSource = dashboard.DataSources(0)
            bubbleMap.DataMember = "Countries"

            ' Loads the map of the world.
            bubbleMap.Area = ShapefileArea.Europe

            ' Provides cities' coordinates.
            bubbleMap.Latitude = New Dimension("Latitude")
            bubbleMap.Longitude = New Dimension("Longitude")

            ' Specifies measures used to evaluate bubble weights and colors.
            bubbleMap.Weight = New Measure("Production", SummaryType.Sum)
            bubbleMap.Color = New Measure("Import", SummaryType.Sum)
            bubbleMap.Color.NumericFormat.FormatType = DataItemNumericFormatType.General

            ' Provides additional values displayed within bubble tooltips.
            bubbleMap.TooltipDimensions.Add(New Dimension("Country"))

            ' Specifies a custom scale and shows map legends.
            CustomizeScale(bubbleMap)
            ShowLegends(bubbleMap)

            ' Adds the Bubble Map dashboard item to the dashboard and opens this
            ' dashboard in the Dashboard Viewer.
            dashboard.Items.Add(bubbleMap)
            dashboardViewer1.Dashboard = dashboard
        End Sub

        Private Sub CustomizeScale(ByVal map As BubbleMapDashboardItem)
            Dim customScale As New CustomScale()
            Dim rangeStops As New List(Of Double)()

            ' Specifies that the absolute scale is used to define a set of range stops.
            customScale.IsPercent = False

            ' Specifies custom range stops.   
            rangeStops.Add(20)
            rangeStops.Add(200)
            rangeStops.Add(500)
            rangeStops.Add(2000)

            ' Adds custom range stops to a custom scale.  
            customScale.RangeStops.AddRange(rangeStops)

            map.ColorScale = customScale
        End Sub

        Private Sub ShowLegends(ByVal map As BubbleMapDashboardItem)
            ' Enables map legends and specifies its position and orientation.
            map.Legend.Visible = True
            map.Legend.Orientation = MapLegendOrientation.Horizontal
            map.WeightedLegend.Visible = True
            map.WeightedLegend.Position = MapLegendPosition.BottomLeft
        End Sub
    End Class
End Namespace

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the ColorScale property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

how-to-bind-a-bubble-map-dashboard-item-to-data-and-customize-its-palette-t119682/CS/Dashboard_CreateBubbleMap/Form1.cs#L60

    map.ColorScale = customScale;
}

VB.NET

how-to-bind-a-bubble-map-dashboard-item-to-data-and-customize-its-palette-t119682/VB/Dashboard_CreateBubbleMap/Form1.vb#L58

    map.ColorScale = customScale
End Sub