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flutterexceptionviewnavigator

Flutter: Exception using Navigator.of(context).pop();

Every time I use Navigator.of(context).pop(); to return to the previous view I always get the

Unhandled Exception: NoSuchMethodError: The method 'call' was called on null.

message.

However, the app successfully goes back to the previous view, but I don't know why I always get this message that sometimes causes a crash. What could it be?

#0      _rootRunUnary (dart:async/zone.dart:1198:47)
#1      _CustomZone.runUnary (dart:async/zone.dart:1100:19)
#2      _FutureListener.handleValue (dart:async/future_impl.dart:143:18)
#3      Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:696:45)
#4      Future._propagateToListeners (dart:async/future_impl.dart:725:32)
#5      Future._completeWithValue (dart:async/future_impl.dart:529:5)
#6      Future._asyncCompleteWithValue.<anonymous closure> (dart:async/future_impl.dart:567:7)
#7      _rootRun (dart:async/zone.dart:1190:13)
#8      _CustomZone.run (dart:async/zone.dart:1093:19)
#9      _CustomZone.runGuarded (dart:async/zone.dart:997:7)
#10     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1037:23)
#11     _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
#12     _startMicrotaskLoop<…>

I usually use an Inkwell associated with an icon to call the method. In example:

InkWell(onTap: () => Navigator.of(context).pop(), 

  child: Icon(Icons.chevron_left_rounded, color: Constants.COLOR_DEF, size: 30));
Solution

  • Nevermind, found the problem.

    Basically, when going from one page to another, I've always called "Navigator.of(context).push(new MaterialPageRoute)" passing also a callback function (if necessary). When that callback function is not passed (null) the error is thrown.

    Thanks anyway to anyone who replied!