Getting Started with Blazor TreeMap Component

30 Jan 202410 minutes to read

This section briefly explains about how to include Blazor TreeMap component in your Blazor Server App and Blazor WebAssembly App using Visual Studio.

The below video demonstrates the customization of Blazor TreeMap component.

Prerequisites

Create a new Blazor App in Visual Studio

You can create a Blazor Server App or Blazor WebAssembly App using Visual Studio via Microsoft Templates or the Syncfusion Blazor Extension.

Install Syncfusion Blazor TreeMap NuGet in the App

To add Blazor TreeMap component in the app, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search and install Syncfusion.Blazor.TreeMap. Alternatively, you can utilize the following package manager command to achieve the same.

Install-Package Syncfusion.Blazor.TreeMap -Version 27.1.48

NOTE

Syncfusion Blazor components are available in nuget.org. Refer to NuGet packages topic for available NuGet packages list with component details.

Register Syncfusion Blazor Service

Open ~/_Imports.razor file and import the Syncfusion.Blazor and Syncfusion.Blazor.TreeMap namespace.

@using Syncfusion.Blazor
@using Syncfusion.Blazor.TreeMap

Now, register the Syncfusion Blazor Service in the ~/Program.cs file of your Blazor Server App or Blazor WebAssembly App.

using Microsoft.AspNetCore.Components;
using Microsoft.AspNetCore.Components.Web;
using Syncfusion.Blazor;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
builder.Services.AddRazorPages();
builder.Services.AddServerSideBlazor();
builder.Services.AddSyncfusionBlazor();

var app = builder.Build();
....
using Microsoft.AspNetCore.Components.Web;
using Microsoft.AspNetCore.Components.WebAssembly.Hosting;
using Syncfusion.Blazor;

var builder = WebAssemblyHostBuilder.CreateDefault(args);
builder.RootComponents.Add<App>("#app");
builder.RootComponents.Add<HeadOutlet>("head::after");

builder.Services.AddScoped(sp => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) });

builder.Services.AddSyncfusionBlazor();
await builder.Build().RunAsync();
....

Add script resources

The script can be accessed from NuGet through Static Web Assets. Reference the script in the <head> of the main page as follows:

  • For .NET 6 Blazor Server app, include it in ~/Pages/_Layout.cshtml file.

  • For .NET 7 Blazor Server app, include it in the ~/Pages/_Host.cshtml file.

  • For Blazor WebAssembly app, include it in the ~/index.html file.

<head>
    ....
    <script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>
</head>

NOTE

Check out the Adding Script Reference topic to learn different approaches for adding script references in your Blazor application.

Add Blazor TreeMap component

Add the Syncfusion Blazor TreeMap component in the ~/Pages/Index.razor file.

  • You can use the DataSource property to load the car sales details in the TreeMap component. Specify a field name from the data source in the WeightValuePath property to calculate the TreeMap item size.
<SfTreeMap DataSource="GrowthReport"
            WeightValuePath="GDP"
            TValue="Country">
</SfTreeMap>

@code {
    public class Country
    {
        public string Name { get; set; }
        public double GDP { get; set; }
    }
    public List<Country> GrowthReport = new List<Country> {
        new Country  {Name="United States", GDP=17946 },
        new Country  {Name="China", GDP=10866 },
        new Country  {Name="Japan", GDP=4123 },
        new Country  {Name="Germany", GDP=3355 },
        new Country  {Name="United Kingdom", GDP=2848 },
        new Country  {Name="France", GDP=2421 },
        new Country  {Name="India", GDP=2073 },
        new Country  {Name="Italy", GDP=1814 },
        new Country  {Name="Brazil", GDP=1774 },
        new Country  {Name="Canada", GDP=1550 }
    };
}
  • Press Ctrl+F5 (Windows) or +F5 (macOS) to launch the application. This will render the Syncfusion Blazor TreeMap component in your default web browser.
Blazor TreeMap Component

Adding labels in Blazor TreeMap items

Add label text to the leaf items in the TreeMap component by setting the field name from data source in the LabelPath property in the TreeMapLeafItemSettings, and it provides information to the user about the leaf items.

<SfTreeMap DataSource="GrowthReport"
            WeightValuePath="GDP"
            TValue="Country">
    <TreeMapLeafItemSettings LabelPath="Name" Fill="lightgray"></TreeMapLeafItemSettings>
</SfTreeMap>

NOTE

Refer to the code block to know about the property value of the GrowthReport.

Blazor TreeMap with Label

Adding title to Blazor TreeMap

Add a title using the Text property in the TreeMapTitleSettings to provide quick information to the user about the items rendered in the TreeMap.

<SfTreeMap DataSource="GrowthReport"
            WeightValuePath="GDP"
            TValue="Country">
    <TreeMapTitleSettings Text="Top 10 countries by GDP Nominal - 2015"></TreeMapTitleSettings>
    <TreeMapLeafItemSettings LabelPath="Name" Fill="lightgray"></TreeMapLeafItemSettings>
</SfTreeMap>

NOTE

Refer to the code block to know the property value of the GrowthReport.

Blazor TreeMap with Title

NOTE

View Sample in GitHub.

Apply color mapping

The color mapping supports customization of item colors based on the underlying value received from the bound data source. Specify the field name from which the values have to be compared for the items in the RangeColorValuePath property in SfTreeMap. Also, specify range value and color in the TreeMapLeafColorMapping. Here, in this example, “Orange” is specified for the range “0 - 3000” and “Green” is specified for the range “3000 - 20000”.

<SfTreeMap DataSource="GrowthReport"
            WeightValuePath="GDP"
            TValue="Country"
            RangeColorValuePath="GDP">
    <TreeMapTitleSettings Text="Top 10 countries by GDP Nominal - 2015"></TreeMapTitleSettings>
    <TreeMapLeafItemSettings LabelPath="Name" Fill="lightgray">
        <TreeMapLeafColorMappings>
            <TreeMapLeafColorMapping StartRange="0" EndRange="3000" Color="@(new string[] { "Orange" })"></TreeMapLeafColorMapping>
            <TreeMapLeafColorMapping StartRange="3000" EndRange="20000" Color="@(new string[] { "Green" })"></TreeMapLeafColorMapping>
        </TreeMapLeafColorMappings>
    </TreeMapLeafItemSettings>
</SfTreeMap>

NOTE

Refer to the code block to know about the property value of the GrowthReport.

Blazor TreeMap with Color Mapping

Enable legend

Legend items are used to denote the color mapping categories and show the legend for the TreeMap by setting the Visible property to true in the TreeMapLegendSettings.

<SfTreeMap DataSource="GrowthReport"
            WeightValuePath="GDP"
            TValue="Country"
            RangeColorValuePath="GDP">
    <TreeMapTitleSettings Text="Top 10 countries by GDP Nominal - 2015"></TreeMapTitleSettings>
    <TreeMapLeafItemSettings LabelPath="Name" Fill="lightgray">
        <TreeMapLeafColorMappings>
            <TreeMapLeafColorMapping StartRange="0" EndRange="3000" Color="@(new string[] { "Orange" })"></TreeMapLeafColorMapping>
            <TreeMapLeafColorMapping StartRange="3000" EndRange="20000" Color="@(new string[] { "Green" })"></TreeMapLeafColorMapping>
        </TreeMapLeafColorMappings>
    </TreeMapLeafItemSettings>
    <TreeMapLegendSettings Visible="true"></TreeMapLegendSettings>
</SfTreeMap>

NOTE

Refer to the code block to know about the property value of the GrowthReport.

Blazor TreeMap with Legend

Enable tooltip

When space constraints prevents from displaying information using data labels, the tooltip comes in handy. The tooltip can be enabled by setting the Visible property to true in the TreeMapTooltipSettings.

<SfTreeMap DataSource="GrowthReport"
            WeightValuePath="GDP"
            TValue="Country"
            RangeColorValuePath="GDP">
    <TreeMapTitleSettings Text="Top 10 countries by GDP Nominal - 2015"></TreeMapTitleSettings>
    <TreeMapLeafItemSettings LabelPath="Name" Fill="lightgray">
        <TreeMapLeafColorMappings>
            <TreeMapLeafColorMapping StartRange="0" EndRange="3000" Color="@(new string[] { "Orange" })"></TreeMapLeafColorMapping>
            <TreeMapLeafColorMapping StartRange="3000" EndRange="20000" Color="@(new string[] { "Green" })"></TreeMapLeafColorMapping>
        </TreeMapLeafColorMappings>
    </TreeMapLeafItemSettings>
    <TreeMapLegendSettings Visible="true"></TreeMapLegendSettings>
    <TreeMapTooltipSettings Visible="true"></TreeMapTooltipSettings>
</SfTreeMap>

NOTE

Refer to the code block to know about the property value of the GrowthReport.

Blazor TreeMap with Tooltip

NOTE

You can also explore our Blazor TreeMap example that shows you how to render and configure the treemap.

See also