Getting Started with Angular Diagram Component

23 Jul 202611 minutes to read

This section explains the steps required to create a simple diagram and demonstrates the basic usage of the diagram component.

Ready to streamline your Syncfusion® Angular development? Discover the full potential of Syncfusion® Angular components with Syncfusion® AI Coding Assistant. Effortlessly integrate, configure, and enhance your projects with intelligent, context-aware code suggestions, streamlined setups, and real-time insights—all seamlessly integrated into your preferred AI-powered IDEs like VS Code, Cursor, Syncfusion® Code Studio and more. Explore Syncfusion® AI Coding Assistant.

Prerequisites

Requirement Version
Angular 12 and above
Node.js 14.0.0 or above, Recommended: Latest Version

Angular supported versions

Angular Version Minimum Syncfusion® Angular Diagram Version
Angular v22 34.1.29
Angular v21 31.1.17
Angular v20 29.2.8
Angular v19 26.1.35
Angular v18 25.2.3
Angular v17 23.2.4
Angular v16 21.1.39
Angular v15 20.4.38
Angular v14 20.2.36
Angular v13 19.4.38 and above
Angular v12 19.3.43

Browser Support

Browser Supported Versions
Google Chrome, including Android & iOS Latest 2 versions
Mozilla Firefox Latest version
Microsoft Edge Latest 2 versions
Apple Safari, including iOS Latest 2 versions

Before You Begin

This guide uses the standalone application structure generated by the latest Angular CLI.

The main files used in this guide are:

  • src/app/app.ts — Defines the root standalone component.
  • src/styles.css — Contains global styles and Syncfusion® theme references.
  • src/index.html — Contains the Angular root element (e.g., <app-root>).

NOTE

In newer Angular CLI standalone projects, the root component may be generated as src/app/app.ts. In NgModule-based Angular projects, the equivalent file is typically src/app/app.component.ts.

NOTE

If your application uses an older NgModule-based structure, import DiagramModule in the application module, such as app.module.ts, instead of adding it to the standalone component imports collection.

Step 1: Set up the Angular environment

Use Angular CLI to create and manage Angular applications. Install Angular CLI globally using the following command:

npm install -g @angular/cli

Step 2: Create an Angular application

Create a new Angular application using the following command.

ng new my-diagram-app

During project creation, Angular CLI may prompt you to choose stylesheet, SSR/SSG, and AI tool configuration options. For this basic Diagram sample, you can use the following options:

  • Stylesheet system: Choose any option. This guide uses CSS for simplicity and applies the Syncfusion® Tailwind 3 theme through CSS imports.
  • SSR and SSG/Pre-rendering: Select No.
  • AI tools configuration: Select None.

Navigate to the project folder:

cd my-diagram-app

Step 3: Install the Syncfusion® Angular Diagram package

All Syncfusion Essential® JS 2 packages are available in the npmjs.com registry.

Install the Angular Diagram package using the following command:

npm install @syncfusion/ej2-angular-diagrams

NOTE

Installing @syncfusion/ej2-angular-diagrams automatically installs the required dependency packages.

NOTE

A Syncfusion® license key is not required for local development. However, a valid Syncfusion® license key must be registered before deploying the application to production. For details, see Registering a Syncfusion® license key.

NOTE

For the latest tested version of the Diagram package, refer to the @syncfusion/ej2-angular-diagrams package page.

Step 4: Add the required styles

The Diagram component needs Syncfusion® theme styles to display correctly. Syncfusion® theme packages include ready-to-use styles for supported components. Install the Tailwind 3 theme package using the following command:

npm install @syncfusion/ej2-tailwind3-theme

Then add the following CSS reference to the src/styles.css file:

@import "../node_modules/@syncfusion/ej2-tailwind3-theme/styles/diagram/index.css";

For the list of available themes, refer to the Themes documentation.

NOTE

Syncfusion® provides multiple built-in themes. If the application uses a different theme, replace the @syncfusion/ej2-tailwind3-theme/styles/diagram/index.css reference with the corresponding theme path, such as @syncfusion/ej2-material3-theme/styles/diagram/index.css.

Step 5: Register the Diagram module and add the component

Import DiagramModule from @syncfusion/ej2-angular-diagrams and add it to the imports collection of the standalone component. Then, add the Angular Diagram component using the <ejs-diagram> selector in the component template.

Update the src/app/app.ts file as follows:

import { Component } from '@angular/core';
import { DiagramModule } from '@syncfusion/ej2-angular-diagrams';

@Component({
  selector: 'app-root',
  standalone: true,
  imports: [DiagramModule],
  template: `<ejs-diagram id="diagram" width="100%" height="580px"></ejs-diagram>`
})
export class App {}

This renders an empty diagram in the application. The next step replaces this code with a more complete example.

NOTE

The component selector must match the root element used in the src/index.html file. Angular CLI commonly uses <app-root></app-root>, so this example uses selector: 'app-root'.

NOTE

The Diagram component must have a valid height. If the height is not set, the Diagram canvas may not be visible.

Step 6: Create your first Diagram with nodes and connectors

This section explains how to create a simple flowchart by adding nodes, customizing their appearance, and connecting them using connectors.

The following example creates a flowchart with four nodes: Start, Process, Decision, and End. It also applies common node and connector settings through the getNodeDefaults and getConnectorDefaults callback bindings.

Replace the entire contents of src/app/app.ts with the following code:

import { Component } from '@angular/core';
import {
  ConnectorModel,
  DiagramModule,
  FlowShapeModel,
  NodeModel
} from '@syncfusion/ej2-angular-diagrams';

@Component({
  selector: 'app-root',
  standalone: true,
  imports: [DiagramModule],
  template: `
    <ejs-diagram
      id="diagram"
      width="100%"
      height="580px"
      [getNodeDefaults]="nodeDefaults"
      [getConnectorDefaults]="connectorDefaults">

      <e-nodes>
        <e-node id="node1" [offsetX]="300" [offsetY]="100" [shape]="terminator">
          <e-node-annotations>
            <e-node-annotation content="Start"></e-node-annotation>
          </e-node-annotations>
        </e-node>

        <e-node id="node2" [offsetX]="300" [offsetY]="200" [shape]="process">
          <e-node-annotations>
            <e-node-annotation content="Process"></e-node-annotation>
          </e-node-annotations>
        </e-node>

        <e-node id="node3" [offsetX]="300" [offsetY]="300" [shape]="decision">
          <e-node-annotations>
            <e-node-annotation content="Decision?"></e-node-annotation>
          </e-node-annotations>
        </e-node>

        <e-node id="node4" [offsetX]="300" [offsetY]="400" [shape]="terminator">
          <e-node-annotations>
            <e-node-annotation content="End"></e-node-annotation>
          </e-node-annotations>
        </e-node>
      </e-nodes>

      <e-connectors>
        <e-connector id="connector1" sourceID="node1" targetID="node2"></e-connector>
        <e-connector id="connector2" sourceID="node2" targetID="node3"></e-connector>
        <e-connector id="connector3" sourceID="node3" targetID="node4"></e-connector>
      </e-connectors>
    </ejs-diagram>
  `
})
export class App {
  public terminator: FlowShapeModel = {
    type: 'Flow',
    shape: 'Terminator'
  };

  public process: FlowShapeModel = {
    type: 'Flow',
    shape: 'Process'
  };

  public decision: FlowShapeModel = {
    type: 'Flow',
    shape: 'Decision'
  };

  public nodeDefaults(node: NodeModel): NodeModel {
    node.width = 140;
    node.height = 50;
    node.style = {
      fill: '#E8F4FF',
      strokeColor: '#357BD2'
    };
    return node;
  }

  public connectorDefaults(connector: ConnectorModel): ConnectorModel {
    connector.type = 'Orthogonal';
    connector.targetDecorator = {
      shape: 'Arrow',
      width: 10,
      height: 10
    };
    return connector;
  }
}

In this example:

Template directives (used inside the <ejs-diagram> template):

Node and connector configuration:

Common defaults applied via callbacks:

  • getNodeDefaults applies common width, height, fill color, and stroke color to all nodes.
  • getConnectorDefaults applies common connector settings, such as orthogonal routing and target arrows.

Step 7: Run the application

Run the application using the following command:

npm start

NOTE

The npm start script runs ng serve by default in an Angular CLI project. You can also run ng serve directly.

Open the generated local URL (http://localhost:4200) in the browser. The application displays the diagram as shown below:

Rendered flowchart with four nodes connected vertically by arrows

NOTE

If port 4200 is already in use, start the app on a different port with ng serve --port 4201.

NOTE

To stop the development server, press Ctrl + C in the terminal where it is running.

NOTE

To build the application for production, run ng build. The generated output is placed in the dist folder.

Next steps

To explore the Diagram component in more depth, refer to the following topics: