GraphColorizer Class

Represents the Graph colorizer utilized to paint shapes that have a common border using different colors.

Namespace: DevExpress.XtraMap

Assembly: DevExpress.XtraMap.v18.1.dll

Declaration

C#

public class GraphColorizer :
    GenericColorizer<ColorizerColorItem>

VB.NET

Public Class GraphColorizer
    Inherits GenericColorizer(Of ColorizerColorItem)

Remarks

To colorize vector items using this colorizer, assign a GraphColorizer object to the VectorItemsLayer.Colorizer property. Then, add ColorizerColorItem objects to the GraphColorizer.ColorItems.

For more information, refer to Colorizers.

Example

This example demonstrates how to paint map contours loaded from a Shapefile (Countries.shp) using the graph colorizer.

To accomplish this task, create a graph colorizer (the GraphColorizer object) and assign it to the VectorItemsLayer.Colorizer property.

Then, specify the desired set of colors in the GenericColorizerItemCollection<T> object that is accessed via the GraphColorizer.ColorItems property.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-colorize-map-contours-loaded-from-shapefiles-using-the-graph-colorizer-e4723

Form1.cs

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;
using DevExpress.XtraMap;

namespace MapGraphColorizer {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e) {

            // Create a map control and specify its dock style.
            MapControl map = new MapControl();
            map.Dock = DockStyle.Fill;

            // Specify the map's initial view.  
            map.ZoomLevel = 2;
            map.CenterPoint = new GeoPoint(38, -100);

            // Create a file layer and assign a shape loader to it.
            map.Layers.Add(new VectorItemsLayer() {
                Data = CreateData(),
                Colorizer = CreateColorizer()
            });

            // Add the map control to the window. 
            this.Controls.Add(map);
        }

        private IMapDataAdapter CreateData() {
            // Create an object to load data from a shapefile.
            ShapefileDataAdapter loader = new ShapefileDataAdapter();

            // Determine the path to the Shapefile.
            Uri baseUri = new Uri(System.Reflection.Assembly.GetEntryAssembly().Location);
            string shapefilePath = "../../Data/Countries.shp";
            loader.FileUri = new Uri(baseUri, shapefilePath);

            return loader;
        }

        private MapColorizer CreateColorizer() {
            // Create a graph colorizer.
            GraphColorizer colorizer = new GraphColorizer();

            // Specify colors for the colorizer.
            colorizer.ColorItems.AddRange(new List<ColorizerColorItem> { 
                new ColorizerColorItem(Color.FromArgb(0xF1, 0xC1, 0x49)), 
                new ColorizerColorItem(Color.FromArgb(0xE5, 0xA8, 0x4D)),
                new ColorizerColorItem(Color.FromArgb(0xC5, 0x64, 0x50)),
                new ColorizerColorItem(Color.FromArgb(0xD6, 0x86, 0x4E)),
                new ColorizerColorItem(Color.FromArgb(0x79, 0x96, 0x89)), 
                new ColorizerColorItem(Color.FromArgb(0xA2, 0xA8, 0x75))
            });
            return colorizer;
        }
    }
}

Form1.vb

Imports System
Imports System.Collections.Generic
Imports System.Drawing
Imports System.Windows.Forms
Imports DevExpress.XtraMap

Namespace MapGraphColorizer
    Partial Public Class Form1
        Inherits Form

        Public Sub New()
            InitializeComponent()
        End Sub

        Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load

            ' Create a map control and specify its dock style.
            Dim map As New MapControl()
            map.Dock = DockStyle.Fill

            ' Specify the map's initial view.  
            map.ZoomLevel = 2
            map.CenterPoint = New GeoPoint(38, -100)

            ' Create a file layer and assign a shape loader to it.
            map.Layers.Add(New VectorItemsLayer() With {.Data = CreateData(), .Colorizer = CreateColorizer()})

            ' Add the map control to the window. 
            Me.Controls.Add(map)
        End Sub

        Private Function CreateData() As IMapDataAdapter
            ' Create an object to load data from a shapefile.
            Dim loader As New ShapefileDataAdapter()

            ' Determine the path to the Shapefile.
            Dim baseUri As New Uri(System.Reflection.Assembly.GetEntryAssembly().Location)
            Dim shapefilePath As String = "../../Data/Countries.shp"
            loader.FileUri = New Uri(baseUri, shapefilePath)

            Return loader
        End Function

        Private Function CreateColorizer() As MapColorizer
            ' Create a graph colorizer.
            Dim colorizer As New GraphColorizer()

            ' Specify colors for the colorizer.
            colorizer.ColorItems.AddRange(New List(Of ColorizerColorItem) From { _
                New ColorizerColorItem(Color.FromArgb(&HF1, &HC1, &H49)), _
                New ColorizerColorItem(Color.FromArgb(&HE5, &HA8, &H4D)), _
                New ColorizerColorItem(Color.FromArgb(&HC5, &H64, &H50)), _
                New ColorizerColorItem(Color.FromArgb(&HD6, &H86, &H4E)), _
                New ColorizerColorItem(Color.FromArgb(&H79, &H96, &H89)), _
                New ColorizerColorItem(Color.FromArgb(&HA2, &HA8, &H75)) _
            })
            Return colorizer
        End Function
    End Class
End Namespace

Related GitHub Examples

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

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-colorize-map-contours-loaded-from-shapefiles-using-the-graph-colorizer-e4723/CS/MapGraphColorizer/Form1.cs#L47

// Create a graph colorizer.
GraphColorizer colorizer = new GraphColorizer();

VB.NET

how-to-colorize-map-contours-loaded-from-shapefiles-using-the-graph-colorizer-e4723/VB/MapGraphColorizer/Form1.vb#L46

' Create a graph colorizer.
Dim colorizer As New GraphColorizer()

Inheritance

Object

MapDisposableObject

ColorizerBase<IColorizerElement>

MapColorizer

PredefinedColorsColorizer

GenericColorizer<ColorizerColorItem>

GraphColorizer