Looks like #16 is happening again in a different line this time around.

[ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: 'package:flutter/src/animation/animation_controller.dart': Failed assertion: line 772 pos 7: '_ticker != null': AnimationController.stop() called after AnimationController.dispose()
package:flutter/…/animation/animation_controller.dart:772
E/flutter (19025): AnimationController methods should not be used after calling dispose.
E/flutter (19025): #0 _AssertionError._doThrowNew (dart:core-patch/errors_patch.dart:51:61)
E/flutter (19025): #1 _AssertionError._throwNew (dart:core-patch/errors_patch.dart:40:5)
E/flutter (19025): #2 AnimationController.stop
package:flutter/…/animation/animation_controller.dart:772
E/flutter (19025): #3 AnimationController.repeat
package:flutter/…/animation/animation_controller.dart:654
E/flutter (19025): #4 BallPulseIndicator.startAnim
package:loading/indicator/ball_pulse_indicator.dart:48
E/flutter (19025): #5 BallPulseIndicator.startAnims.
package:loading/indicator/ball_pulse_indicator.dart:55
E/flutter (19025): #6 new Future.delayed. (dart:async/future.dart:393:39)
E/flutter (19025): #7 _rootRun (dart:async/zone.dart:1418:47)
E/flutter (19025): #8 _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter (19025): #9 _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
E/flutter (19025): #10 _CustomZone.bindCallbackGuarded. (dart:async/zone.dart:1276:23)
E/flutter (19025): #11 _rootRun (dart:async/zone.dart:1426:13)
E/flutter (19025): #12 _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter (19025): #13 _CustomZone.bindCallback. (dart:async/zone.dart:1260:23)
E/flutter (19025): #14 Timer._createTimer. (dart:async-patch/timer_patch.dart:18:15)
E/flutter (19025): #15 _Timer._runTimers (dart:isolate-patch/timer_impl.dart:395:19)
E/flutter (19025): #16 _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:426:5)
E/flutter (19025): #17 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:192:12)