1. Dart
2. dart:html
3. TransitionEvent
4. propertyName property

TransitionEvent class

1. Constructors
2. TransitionEvent
3. Properties
4. elapsedTime
5. propertyName
6. pseudoElement
7. bubbles
8. cancelable
9. composed
10. currentTarget
11. defaultPrevented
12. eventPhase
13. hashCode
14. isTrusted
15. matchingTarget
16. path
17. runtimeType
18. target
19. timeStamp
20. type
21. Methods
22. composedPath
23. noSuchMethod
24. preventDefault
25. stopImmediatePropagation
26. stopPropagation
27. toString
28. Operators
29. operator ==

String get propertyName native;