Extending SAP Fiori apps using controller extensions is a common practice in SAPUI5 development. Controller extensions allow you to enhance the behavior of existing controllers without modifying the original code directly. Here's how you can add a controller extension to extend SAP Fiori apps based on the SAPUI5 framework:

Step 1: Create a New JavaScript File

Create a new JavaScript file for your controller extension. For example, you can name it MyExtensionController.js.

Step 2: Define the Controller Extension

In your MyExtensionController.js file, define your controller extension. You can do this by creating a new controller and extending the existing Fiori app's controller. Here's an example:

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sap.ui.define([ "sap/ui/core/mvc/Controller" ], function(Controller) { "use strict"; return Controller.extend("your.namespace.MyExtensionController", { onInit: function() { // Your initialization code here }, // Add additional methods and event handlers as needed }); });

Step 3: Register the Controller Extension in the Manifest File

In the manifest file (manifest.json), you need to register your controller extension under the "sap.ui5" section. Add an entry for your extension in the "extends" property of the corresponding Fiori app's controller:

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{ "sap.ui5": { "extends": { "extensions": { "your.namespace.MyOriginalController": { "controllerName": "your.namespace.MyExtensionController" } } } } }

Replace "your.namespace.MyOriginalController" with the fully qualified name of the Fiori app's original controller that you want to extend. Replace "your.namespace.MyExtensionController" with the fully qualified name of your controller extension.

Step 4: Use the Extended Controller in Your Views

In your XML views, refer to the extended controller using the controllerExtension attribute:

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<mvc:View xmlns:mvc="sap.ui.core.mvc" controllerName="your.namespace.ViewController" xmlns="sap.m" controllerExtension="your.namespace.MyExtensionController"> <!-- Your view content here --> </mvc:View>

Replace "your.namespace.ViewController" with the fully qualified name of the original Fiori app's view controller.

By following these steps, you've successfully added a controller extension to extend SAP Fiori apps. Your extension can now contain additional methods, event handlers, or overrides that enhance the behavior of the original Fiori app's controller without modifying its code directly.