The App Frontend

The frontend of an app is concerned mainly with data visualization and user interaction. Frontend code:

• Always runs in a web browser.
• Gets access to the data in an iModel by making requests on a backend.
• May use the display system to visualize the contents of an iTwin.

The following app configurations are supported:

• Web app - See browser compatibility
• Desktop app
• Mobile app

See the app architecture overview for more on app structure.

An app's frontend always implements its own frontend script and resources.

An app's frontend will often depend on npm packages to help implement its GUI.

An app's frontend script requires the @itwin/core-frontend npm package. The common packages will also be required.

These packages provide the following services:

• Log in and obtain AccessTokens
• Open a "connection" to an iModel
• Adminstration and configuration via the IModelApp class
• Localization of strings and user interface
• Writing Tools for handling events from users
• Communicating with the Backend via an RpcInterface
• Displaying Views of iModels
• Executing ECSQL queries on iModels
• Storing User Preferences for iTwins and iModels
• Formatting Quantities
• Writing Extensions that can load on demand into an iTwin.js frontend application

Web browser compatibility

See Supported Platforms Page