Add clarification about on_settings callback

README.md

@@ -350,6 +350,14 @@ function on_action()
 end
 ```
 
+To change the action of the settings icon in the widget's edit menu, you can add the on_settings() function to the script. It will be called every time the user presses the icon.
+
+```
+function on_action()
+    ui:show_toast("Settings icon clicked!")
+end
+```
+
 ## Application management
 
 * `apps:apps([sort_by])` - returns the table of tables of all installed applications;