Assembly Requirements

Required Assembly:

• Syncfusion.SfSunburstChart.WPF

NuGet Package:

Install-Package Syncfusion.SfSunburstChart.WPF

Minimum .NET Framework: 4.5 or higher

Implementing Sunburst Charts

Guide for implementing the Syncfusion WPF Sunburst Chart (SfSunburstChart) control for visualizing hierarchical data in concentric circular rings. The sunburst chart displays multi-level categorical data where each ring represents a level in the hierarchy, with the center representing the root and outer rings representing deeper levels.

When to Use This Skill

Use this skill when you need to:

• Visualize hierarchical data with multiple levels in a circular layout
• Display organizational structures (departments, teams, roles)
• Show file system hierarchies (folders, subfolders, files)
• Present sales data organized by region, category, product, subcategory
• Implement drill-down experiences with interactive zooming
• Create multi-level circular visualizations where size represents value
• Display tree-structured data in a compact, visual format
• Enable interactive exploration of nested categorical data

Sunburst charts are ideal when you have 2-5 levels of hierarchical data and want to show both the structure and relative sizes of categories.

Component Overview

The SfSunburstChart is a specialized WPF control that visualizes hierarchical data in concentric circles:

Key Capabilities:

• Multi-level hierarchies: Support for 2-5+ hierarchical levels
• Data binding: MVVM-compatible with IEnumerable data sources
• Interactive features: Tooltips, selection, zooming/drill-down
• Visual customization: Color palettes, data labels, legends
• Animations: FadeIn and Rotation animations for smooth rendering
• Responsive design: Customizable radius and angles

Core Properties:

• ItemsSource – Data collection (hierarchical data model)
• ValueMemberPath – Property name for segment sizing
• Levels – Collection defining each hierarchy level
• GroupMemberPath – Property for each level's grouping

Documentation and Navigation Guide

Getting Started

📄 Read: [references/getting-started.md](references/getting-started.md)

Use this reference when:

• Setting up a new sunburst chart project
• Adding assembly references (Syncfusion.SfSunburstChart.WPF)
• Creating data models and ViewModels
• Binding data to the chart
• Adding basic visual elements (header, legend, data labels)
• Understanding complete working examples

Topics covered:

• Assembly references and installation
• Namespace imports (XAML and C#)
• Data model structure for hierarchical data
• ViewModel initialization with ObservableCollection
• Basic chart configuration (ItemsSource, ValueMemberPath)
• Adding header, legend, and data labels
• Theme integration

Hierarchical Levels Configuration

📄 Read: [references/hierarchical-levels.md](references/hierarchical-levels.md)

Use this reference when:

• Defining the hierarchy structure
• Configuring multiple levels (2-5+ levels)
• Understanding GroupMemberPath mapping
• Organizing data by categories and subcategories

Topics covered:

• SunburstHierarchicalLevel overview
• Levels collection management
• GroupMemberPath property usage
• Multi-level hierarchy examples
• Level ordering and structure

Data Labels

📄 Read: [references/data-labels.md](references/data-labels.md)

Use this reference when:

• Showing category names and values on segments
• Customizing label appearance and positioning
• Handling label overflow (Hide or Trim)
• Rotating labels for better readability
• Creating custom label templates

Topics covered:

• Enabling/disabling labels (ShowLabel)
• LabelOverflowMode (Hide, Trim)
• LabelRotationMode (Normal, Angle)
• Font customization (FontFamily, FontSize, FontStyle, FontWeight)
• Custom templates (LabelTemplate)
• Foreground color customization

Legend Configuration

📄 Read: [references/legend.md](references/legend.md)

Use this reference when:

• Adding a legend to identify categories
• Customizing legend icons and layout
• Positioning the legend (Left, Right, Top, Bottom)
• Implementing legend interactivity (click to select/hide)
• Creating custom legend templates

Topics covered:

• Legend initialization
• LegendIcon shapes (Circle, Pentagon, Rectangle, etc.)
• Icon sizing (IconHeight, IconWidth)
• Custom legend templates (LegendIconTemplate)
• Positioning (DockPosition)
• Legend interactivity (ClickAction: ToggleSegmentSelection, ToggleSegmentVisibility)

Animation

📄 Read: [references/animation.md](references/animation.md)

Use this reference when:

• Adding smooth entry animations
• Configuring animation duration
• Choosing between FadeIn and Rotation animations

Topics covered:

• EnableAnimation property
• AnimationDuration configuration
• AnimationType options (FadeIn, Rotation)
• Performance considerations

Visual Customization

📄 Read: [references/visual-customization.md](references/visual-customization.md)

Use this reference when:

• Applying color palettes (predefined or custom)
• Creating custom color schemes
• Adjusting chart dimensions (radius, inner radius)
• Customizing start and end angles
• Using gradient brushes

Topics covered:

• Predefined palettes (Metro, AutumnBrights, FloraHues, etc.)
• Custom palettes (ColorModel, CustomBrushes)
• Gradient brush examples
• Region properties (StartAngle, EndAngle, Radius, InnerRadius)
• Visual structure customization

Interactivity Features

📄 Read: [references/interactivity.md](references/interactivity.md)

Use this reference when:

• Adding tooltips on hover
• Implementing segment selection
• Enabling drill-down/zooming
• Configuring interactive behaviors
• Customizing user experience

Topics covered:

• Tooltips: ShowToolTip, alignment, offset, duration, custom templates
• Selection: SelectionDisplayMode, SelectionMode, SelectionType, SelectionBrush
• Zooming: SunburstZoomingBehavior, toolbar configuration, drill-down

Event Handling

📄 Read: [references/events.md](references/events.md)

Use this reference when:

• Responding to segment creation
• Handling selection changes
• Customizing segments dynamically
• Implementing custom behaviors on user actions

Topics covered:

• SegmentCreated event
• SelectionChanged event
• Event argument properties
• Dynamic segment customization
• Event handler patterns

Quick Start Example

Here's a minimal example to create a sunburst chart showing employee distribution:

1. Add Assembly Reference

<!-- In your XAML, add namespace -->
<Window xmlns:sunburst="clr-namespace:Syncfusion.UI.Xaml.SunburstChart;assembly=Syncfusion.SfSunburstChart.WPF">

2. Create Data Model

public class EmployeeData
{
    public string Country { get; set; }
    public string Department { get; set; }
    public string Team { get; set; }
    public double EmployeeCount { get; set; }
}

3. Create ViewModel

public class ViewModel
{
    public ObservableCollection<EmployeeData> Data { get; set; }
    
    public ViewModel()
    {
        Data = new ObservableCollection<EmployeeData>
        {
            new EmployeeData { Country = "USA", Department = "Sales", Team = "Field Sales", EmployeeCount = 45 },
            new EmployeeData { Country = "USA", Department = "Sales", Team = "Inside Sales", EmployeeCount = 30 },
            new EmployeeData { Country = "USA", Department = "Engineering", Team = "Development", EmployeeCount = 85 },
            new EmployeeData { Country = "USA", Department = "Engineering", Team = "QA", EmployeeCount = 35 },
            new EmployeeData { Country = "India", Department = "Engineering", Team = "Development", EmployeeCount = 120 },
            new EmployeeData { Country = "India", Department = "Engineering", Team = "QA", EmployeeCount = 40 },
            new EmployeeData { Country = "UK", Department = "Sales", Team = "Field Sales", EmployeeCount = 25 },
            new EmployeeData { Country = "UK", Department = "Marketing", Team = "Digital", EmployeeCount = 20 }
        };
    }
}

4. XAML Configuration

<sunburst:SfSunburstChart ItemsSource="{Binding Data}" ValueMemberPath="EmployeeCount"
                          Header="Employee Distribution" FontSize="20">
    
    <!-- Define hierarchy levels -->
    <sunburst:SfSunburstChart.Levels>
        <sunburst:SunburstHierarchicalLevel GroupMemberPath="Country"/>
        <sunburst:SunburstHierarchicalLevel GroupMemberPath="Department"/>
        <sunburst:SunburstHierarchicalLevel GroupMemberPath="Team"/>
    </sunburst:SfSunburstChart.Levels>
    
    <!-- Add legend -->
    <sunburst:SfSunburstChart.Legend>
        <sunburst:SunburstLegend DockPosition="Left"/>
    </sunburst:SfSunburstChart.Legend>
    
    <!-- Add data labels -->
    <sunburst:SfSunburstChart.DataLabelInfo>
        <sunburst:SunburstDataLabelInfo ShowLabel="True"/>
    </sunburst:SfSunburstChart.DataLabelInfo>
    
</sunburst:SfSunburstChart>

5. Set DataContext

public MainWindow()
{
    InitializeComponent();
    this.DataContext = new ViewModel();
}

Common Patterns

Pattern 1: Hierarchical Data with 3-4 Levels

<sunburst:SfSunburstChart ItemsSource="{Binding HierarchicalData}" 
                          ValueMemberPath="Value"
                          Palette="Metro">
    <sunburst:SfSunburstChart.Levels>
        <sunburst:SunburstHierarchicalLevel GroupMemberPath="Level1"/>
        <sunburst:SunburstHierarchicalLevel GroupMemberPath="Level2"/>
        <sunburst:SunburstHierarchicalLevel GroupMemberPath="Level3"/>
        <sunburst:SunburstHierarchicalLevel GroupMemberPath="Level4"/>
    </sunburst:SfSunburstChart.Levels>
</sunburst:SfSunburstChart>

Use when: Displaying organizational structures, file systems, or multi-level sales data.

Pattern 2: Interactive Chart with Selection and Tooltips

<sunburst:SfSunburstChart ItemsSource="{Binding Data}" ValueMemberPath="Value">
    
    <sunburst:SfSunburstChart.Behaviors>
        <!-- Enable selection -->
        <sunburst:SunburstSelectionBehavior EnableSelection="True"
                                           SelectionMode="MouseClick"
                                           SelectionType="Single"/>
        
        <!-- Enable tooltips -->
        <sunburst:SunburstToolTipBehavior ShowToolTip="True"
                                         ShowDuration="3000"/>
    </sunburst:SfSunburstChart.Behaviors>
    
</sunburst:SfSunburstChart>

Use when: Users need to interact with segments for detailed information.

Pattern 3: Drill-Down with Zooming

<sunburst:SfSunburstChart ItemsSource="{Binding Data}" 
                          ValueMemberPath="Value">
    
    <sunburst:SfSunburstChart.Behaviors>
        <!-- Enable zooming for drill-down -->
        <sunburst:SunburstZoomingBehavior EnableZooming="True"
                                         ToolBarHorizontalAlignment="Right"
                                         ToolBarVerticalAlignment="Top"/>
    </sunburst:SfSunburstChart.Behaviors>
    
</sunburst:SfSunburstChart>

Use when: Users need to explore deep hierarchies by zooming into specific categories.

Pattern 4: Custom Palette with Gradient Brushes

<sunburst:SfSunburstChart ItemsSource="{Binding Data}" ValueMemberPath="Value" Palette="Custom">
    
    <sunburst:SfSunburstChart.ColorModel>
        <sunburst:SunburstColorModel>
            <sunburst:SunburstColorModel.CustomBrushes>
                <LinearGradientBrush>
                    <GradientStop Color="#FF6B88E6" Offset="0"/>
                    <GradientStop Color="#FF2C5AA0" Offset="1"/>
                </LinearGradientBrush>
                <LinearGradientBrush>
                    <GradientStop Color="#FFE67E6B" Offset="0"/>
                    <GradientStop Color="#FFA0422C" Offset="1"/>
                </LinearGradientBrush>
            </sunburst:SunburstColorModel.CustomBrushes>
        </sunburst:SunburstColorModel>
    </sunburst:SfSunburstChart.ColorModel>
    
</sunburst:SfSunburstChart>

Use when: Matching corporate branding or creating custom color themes.

Pattern 5: Animated Entry with Rotation

<sunburst:SfSunburstChart ItemsSource="{Binding Data}" 
                          ValueMemberPath="Value"
                          EnableAnimation="True"
                          AnimationType="Rotation"
                          AnimationDuration="1500">
    <!-- Chart configuration -->
</sunburst:SfSunburstChart>

Use when: Adding visual polish with smooth entry animations.

Key Properties

Core Data Binding

• ItemsSource – IEnumerable data source (hierarchical data collection)
• ValueMemberPath – Property name for segment size calculation
• Levels – Collection of SunburstHierarchicalLevel defining hierarchy
• GroupMemberPath (on levels) – Property for category grouping at each level

Visual Elements

• Header – Chart title
• Legend – SunburstLegend for category identification
• DataLabelInfo – SunburstDataLabelInfo for segment labels
• Palette – Color scheme (Metro, AutumnBrights, Custom, etc.)
• ColorModel – Custom brush definitions

Region Properties

• Radius – Chart outer radius (0.0 to 1.0, default: 0.9)
• InnerRadius – Center circle radius (0.0 to 1.0, default: 0.2)
• StartAngle – Starting angle in degrees (default: 0)
• EndAngle – Ending angle in degrees (default: 360)

Animation

• EnableAnimation – Enable/disable entry animation
• AnimationType – FadeIn or Rotation
• AnimationDuration – Animation time in milliseconds

Behaviors

• SunburstToolTipBehavior – Tooltip configuration
• SunburstSelectionBehavior – Selection interactivity
• SunburstZoomingBehavior – Drill-down/zooming

Common Use Cases

Use Case 1: Organizational Hierarchy Visualization

Scenario: Display company structure by region, department, team, and role.

Solution:

• 4 hierarchy levels (Region → Department → Team → Role)
• ValueMemberPath = "EmployeeCount"
• Enable selection to highlight departments
• Add tooltips showing employee counts

Use Case 2: File System Explorer

Scenario: Visualize disk usage by folder hierarchy.

Solution:

• 3-5 hierarchy levels (Drive → Folder → Subfolder → File)
• ValueMemberPath = "SizeInBytes"
• Enable zooming for drill-down navigation
• Custom palette showing size with color intensity

Use Case 3: Sales Dashboard

Scenario: Display sales by region, category, product, and SKU.

Solution:

• 4 hierarchy levels (Region → Category → Product → SKU)
• ValueMemberPath = "SalesAmount"
• Interactive legend with ToggleSegmentVisibility
• Custom data labels showing sales figures

Use Case 4: Budget Allocation Viewer

Scenario: Show budget distribution across departments and projects.

Solution:

• 3 hierarchy levels (Department → Project → Phase)
• ValueMemberPath = "BudgetAmount"
• Custom color palette matching budget categories
• Selection highlighting with custom brushes

Use Case 5: Website Analytics Hierarchy

Scenario: Display website traffic by country, page category, and page.

Solution:

• 3 hierarchy levels (Country → Category → Page)
• ValueMemberPath = "PageViews"
• Animated entry (FadeIn)
• Tooltips with additional metrics (bounce rate, time on page)

Best Practices

1. Data Structure: Ensure your data model has distinct properties for each hierarchy level and a numeric property for ValueMemberPath.

1. Level Count: Limit to 3-5 levels for optimal readability. Too many levels create overcrowded outer rings.

1. Value Consistency: Ensure ValueMemberPath points to positive numeric values representing size/count/amount.

1. Label Readability: Use LabelOverflowMode="Trim" or "Hide" to prevent label clutter on smaller segments.

1. Interactive Features: Combine tooltips with selection for the best user experience. Add zooming for deep hierarchies.

1. Performance: For large datasets (1000+ items), consider data aggregation or limiting visible levels.

1. Color Consistency: Use predefined palettes for consistency or create custom palettes matching your application's theme.

1. MVVM Pattern: Implement INotifyPropertyChanged in your ViewModel for dynamic data updates.

Troubleshooting

Chart not displaying:

• Verify ItemsSource binding is correct
• Check that ValueMemberPath matches a numeric property
• Ensure at least one SunburstHierarchicalLevel is defined
• Verify data collection is not empty

Segments not sized correctly:

• Confirm ValueMemberPath points to a numeric property
• Check for null or negative values in the data
• Ensure property name matches exactly (case-sensitive)

Labels overlapping:

• Set LabelOverflowMode="Hide" or "Trim"
• Reduce FontSize on DataLabelInfo
• Consider hiding labels on smaller segments

Legend not showing:

• Verify Legend property is set (not null)
• Check that DockPosition is valid
• Ensure first-level categories exist in data