AUDIO_VIDEO_HEADPHONES property Null safety

1. printersdk
2. printer_models
3. BluetoothDeviceClass
4. AUDIO_VIDEO_HEADPHONES property

BluetoothDeviceClass class

1. Constructors
2. BluetoothDeviceClass
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Static properties
12. AUDIO_VIDEO_CAMCORDER
13. AUDIO_VIDEO_CAR_AUDIO
14. AUDIO_VIDEO_HANDSFREE
15. AUDIO_VIDEO_HEADPHONES
16. AUDIO_VIDEO_HIFI_AUDIO
17. AUDIO_VIDEO_LOUDSPEAKER
18. AUDIO_VIDEO_MICROPHONE
19. AUDIO_VIDEO_PORTABLE_AUDIO
20. AUDIO_VIDEO_RESERVED
21. AUDIO_VIDEO_SET_TOP_BOX
22. AUDIO_VIDEO_UNCATEGORIZED
23. AUDIO_VIDEO_VCR
24. AUDIO_VIDEO_VIDEO_CAMERA
25. AUDIO_VIDEO_VIDEO_CONFERENCING
26. AUDIO_VIDEO_VIDEO_DISPLAY_AND_LOUDSPEAKER
27. AUDIO_VIDEO_VIDEO_GAMING_TOY
28. AUDIO_VIDEO_VIDEO_MONITOR
29. AUDIO_VIDEO_WEARABLE_HEADSET
30. BITMASK
31. COMPUTER_DESKTOP
32. COMPUTER_HANDHELD_PC_PDA
33. COMPUTER_LAPTOP
34. COMPUTER_PALM_SIZE_PC_PDA
35. COMPUTER_SERVER
36. COMPUTER_UNCATEGORIZED
37. COMPUTER_WEARABLE
38. HEALTH_BLOOD_PRESSURE
39. HEALTH_DATA_DISPLAY
40. HEALTH_GLUCOSE
41. HEALTH_PULSE_OXIMETER
42. HEALTH_PULSE_RATE
43. HEALTH_THERMOMETER
44. HEALTH_UNCATEGORIZED
45. HEALTH_WEIGHING
46. PHONE_CELLULAR
47. PHONE_CORDLESS
48. PHONE_ISDN
49. PHONE_MODEM_OR_GATEWAY
50. PHONE_SMART
51. PHONE_UNCATEGORIZED
52. TOY_CONTROLLER
53. TOY_DOLL_ACTION_FIGURE
54. TOY_GAME
55. TOY_ROBOT
56. TOY_UNCATEGORIZED
57. TOY_VEHICLE
58. WEARABLE_GLASSES
59. WEARABLE_HELMET
60. WEARABLE_JACKET
61. WEARABLE_PAGER
62. WEARABLE_UNCATEGORIZED
63. WEARABLE_WRIST_WATCH