SAP UI5 is a robust framework for building enterprise-grade web applications with a rich user experience, commonly used in SAP Fiori apps and other SAP solutions. To deliver high-quality, maintainable, and performant UI5 applications, developers should follow established best practices throughout the development lifecycle.
This article outlines essential UI5 development best practices focusing on architecture, performance, coding standards, and maintainability to help SAP professionals build scalable UI5 applications.
SAP UI5 is based on the Model-View-Controller (MVC) design pattern, promoting separation of concerns:
- Model: Manages application data and business logic.
- View: Responsible for UI layout and elements (XML, JS, or JSON views).
- Controller: Handles user interaction logic, event handling, and communication between model and view.
Best Practice:
- Keep controllers lean, containing only event handling and UI logic.
- Encapsulate business logic in models or separate modules.
- Avoid putting UI elements or logic directly in the controller or model.
While UI5 supports XML, JS, and JSON views, XML views are preferred for their:
- Readability and maintainability.
- Clear separation between UI structure and logic.
- Native support for data binding and UI5 controls.
Tip: Use UI5’s XML namespaces and fragments to modularize views and reuse UI components.
¶ 3. Implement Data Binding and Models Effectively
UI5 supports different model types like:
- JSONModel for client-side data.
- ODataModel for backend data via OData services.
- ResourceModel for internationalization (i18n).
Best Practices:
- Use two-way data binding where applicable to sync UI and data automatically.
- Minimize the use of global models; scope models to views or components as needed.
- For large datasets, implement server-side filtering, sorting, and paging instead of loading all data on the client.
¶ 4. Follow Naming Conventions and Coding Standards
Consistent naming and coding styles improve maintainability:
- Use meaningful and descriptive IDs for controls.
- Name controllers and views according to their functionality (
ViewName.controller.js).
- Follow JavaScript coding standards, including indentation, camelCase for variables and functions, and uppercase for classes.
Tip: Use linting tools like ESLint with UI5 configurations to enforce coding standards.
Performance is crucial, especially for large enterprise applications.
Performance Tips:
- Use Fragments to reuse UI parts without loading full views.
- Lazy load components and views as needed.
- Avoid unnecessary rerendering by using aggregation binding properly.
- Minimize synchronous calls; prefer asynchronous OData calls.
- Use UI5’s built-in controls optimized for large datasets, like
sap.ui.table.Table or sap.m.Table.
Leverage the Component.js lifecycle to encapsulate app initialization, routing, and models. This approach:
- Supports modular development.
- Simplifies reuse of components in other apps.
- Enables better routing and navigation handling.
¶ 7. Implement Routing and Navigation Properly
Routing defines navigation in SPA (Single Page Applications):
- Use the UI5 Router configured in
manifest.json.
- Define routes and targets clearly.
- Implement pattern matching and route parameters for dynamic navigation.
- Keep routing logic in the component or dedicated router module.
¶ 8. Handle Internationalization (i18n)
For global apps, support multiple languages:
- Use
ResourceModel and .properties files for texts.
- Avoid hardcoded strings; always reference keys from the i18n model.
- Use UI5 formatting utilities for date, time, and numbers based on locale.
¶ 9. Write Modular and Reusable Code
- Create reusable controls and fragments for common UI patterns.
- Use utility libraries or helper modules for shared functions.
- Avoid duplicating code or UI components.
¶ 10. Implement Robust Error Handling and Logging
- Use UI5 message handling (
sap.m.MessageToast, sap.m.MessageBox) for user feedback.
- Implement error handling in OData calls and show meaningful messages.
- Use logging for debugging and production diagnostics with
jQuery.sap.log.
- Sanitize user inputs and escape outputs to prevent XSS attacks.
- Use HTTPS and authentication mechanisms.
- Avoid exposing sensitive data in client models or URLs.
- Write unit tests for controllers and modules using QUnit.
- Use OPA5 for end-to-end acceptance testing.
- Integrate tests into CI/CD pipelines to ensure code quality.
Following these best practices will help you develop efficient, maintainable, and user-friendly SAP UI5 applications. Whether you’re building simple apps or complex enterprise solutions, adhering to standards around architecture, performance, code quality, and testing will result in a better product and smoother maintenance over time.