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Version: 3.9.0-beta.62 (Latest)

Extending App Types and Services in Your Application

This documentation provides an overview and examples on how to use and extend withAppTypes, integrate custom properties, and add services in the global namespace of the application. This helps in enhancing the application's modularity and extensibility.

Overview of withAppTypes

The withAppTypes function is a TypeScript utility that extends the base properties of components or modules with the application's core service and manager types. It allows for a more flexible and type-safe way to pass around core functionality and custom properties.

Using withAppTypes

withAppTypes can be enhanced using generics to include custom properties. This is particularly useful for passing additional data or configurations specific to your component or service.

Extending with Custom Properties

You can extend withAppTypes to include custom properties by defining an interface for the props you need. For example:

interface ColorbarProps {
viewportId: string;
displaySets: Array<any>;
colorbarProperties: ColorbarProperties;

export function Colorbar({
commandsManager, // injected type
servicesManager, // injected type
}: withAppTypes<ColorbarProps>): ReactElement {
// Component logic here

In this example, ColorbarProps is a custom interface that extends the application types through withAppTypes.

Typing the custom extensions's new services

Extensions can define additional services that integrate seamlessly into the application's global service architecture, and will be available on the ServicesManager for use across the application.

Adding the extension's services Types

Declare your service in the global namespace and use it across your application as demonstrated below:


declare global {
namespace AppTypes {
// only add if you need direct access to the service ex. AppTypes.MicroscopyService
export type MicroscopyService = MicroscopyServiceType;
// add to the global Services interface, and to withAppTypes
export interface Services {
microscopyService?: MicroscopyServiceType;

Doing the above adds the microscopyService to the global Services interface, which ServicesManager uses by default public services: AppTypes.Services = {}; to type services, and is also used by withAppTypes to inject services into components. You will also get access to the seperate services via AppTypes.YourServiceName in your application.

export function CustomComponent({
}: withAppTypes<CustomComponentProps>): ReactElement {
const { microscopyService } =;
microscopyService.someMethod(); // auto completation available

export function CustomComponent2(
microscopyService: AppTypes.MicroscopyService,
): ReactElement {
microscopyService.someMethod(); // auto completation available