Lesson 2 - Create a Sunburst and Bind it to Data

  • 5 minutes to read

This tutorial explains how to create an application with a sunburst, bind it to data, and configure the sunburst's center label and colorizer settings.

Step 1. Create an Application and Add the Sunburst to the Form

Run the Microsoft® Visual Studio® 2015 or 2017. Create a Windows Forms project and add the SunburstControl to the Form (see the Steps 1-3 in Lesson 1).

Step 2. Describe Data Objects

Right-click the project in the Solution Explorer window and select the Add | Class... item.

add-new-class-to-project

The Add New Item dialog appears.

Specify the class name as ProductInfo.cs in the Add New Item dialog and click Add.

product-info-class

Replace the auto-generated ProductInfo class declaration with the following code.


public class ProductInfo {
    public string Product { get; set; }
    public string Category { get; set; }
    public string Country { get; set; }
    public double Income { get; set; }
}

Step 3. Configure a Data Source

Create the method that returns the data objects list that will be used as the sunburst's data source. Add the method's code to the Form class.


List<ProductInfo> CreateProductInfos() {
    return new List<ProductInfo> {
        new ProductInfo {Product = "Wheat",         Country = "China",  Income = 129770, Category = "Cereals"},
        new ProductInfo {Product = "Maize",         Country = "USA",    Income = 370971, Category = "Cereals"},
        new ProductInfo {Product = "Rice",          Country = "China",  Income = 142864, Category = "Cereals"},
        new ProductInfo {Product = "Soybean",       Country = "USA",    Income = 119533, Category = "Oilseeds"},
        new ProductInfo {Product = "Protein meals", Country = "China", Income = 93306,  Category = "Oilseeds"},
        new ProductInfo {Product = "Sugar (tq)",    Country = "India",  Income = 26000,  Category = "Sugar"},
        new ProductInfo {Product = "Sugar beet",    Country = "Russia", Income = 49473,  Category = "Sugar"},
        new ProductInfo {Product = "Sugar cane",    Country = "India",  Income = 384795, Category = "Sugar"},
        new ProductInfo {Product = "Milk",          Country = "India",  Income = 169320, Category = "Dairy"}
     };
}

Step 4. Specify the Sunburst's Data Adapter

Assign the SunburstFlatDataAdapter to the SunburstControl.DataAdapter property.

assign-flat-data-adapter-to-sunburst

Set the SunburstFlatDataAdapter.ValueDataMember property to Income.

specify-value-data-member

Set the SunburstFlatDataAdapter.LabelDataMember property to Product.

specify-label-data-member

Click the SunburstFlatDataAdapter.GroupDataMembers property's ellipsis button. In the invoked editor, add the following lines to group products by countries and categories.

Country

Category

specify-group-data-members

In this step, use the CreateProductInfos method (Step 3) to specify SunburstFlatDataAdapter.DataSource. Handle the Form.Load event and change the event handler's code as follows.


using DevExpress.XtraTreeMap;
// ...
private void Form1_Load(object sender, EventArgs e) {
    SunburstFlatDataAdapter dataAdapter = sunburstControl1.DataAdapter as SunburstFlatDataAdapter;
    if(dataAdapter != null) {
        dataAdapter.DataSource = CreateProductInfos();
    }
}

Step 5. Change the Center Label Text

Specify the SunburstCenterLabel.TextPattern property to Total: {TV} to modify the Center Label's text. The {TV} placeholder allows you to display the sum of top-level item values.

sunburst-center-label-text-pattern

Step 6. Configure Colorizer Settings

Colorizers automatically provide sunburst items with colors. You use the Gradient Colorizer in this step. Assign SunburstGradientColorizer to the SunburstControl.Colorizer property.

assign-colorizer

Define how color transparency should change from top-level items to their child items. Set the SunburstGradientColorizer.Max property to 0.9 and SunburstGradientColorizer.Min to 0.4.

colorizer-min-max-values

Select the Pastel Kit palette in the SunburstPaletteColorizerBase.Palette property's drop-down list.

sunburst-colorizer-palette

Result

Run the project to see the result.

sunburst-lesson2-result