未处理的异常：在迁移到空安全之后查找停用的小部件的祖先是不安全的 Navigator.push

Question

我已经将项目的所有包迁移到 null safety。

由于有人认为我必须处理 Android (Kotlin)，扩展第三方库。这样做之后，现在我收到以下错误：

E/flutter (14210): [ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: Looking up a deactivated widget's ancestor is unsafe.
E/flutter (14210): At this point the state of the widget's element tree is no longer stable.
E/flutter (14210): To safely refer to a widget's ancestor in its dispose() method, save a reference to the ancestor by calling dependOnInheritedWidgetOfExactType() in the widget's didChangeDependencies() method.
E/flutter (14210): #0      Element._debugCheckStateIsActiveForAncestorLookup.<anonymous closure>
package:flutter/…/widgets/framework.dart:3944
E/flutter (14210): #1      Element._debugCheckStateIsActiveForAncestorLookup
package:flutter/…/widgets/framework.dart:3958
E/flutter (14210): #2      Element.findAncestorStateOfType
package:flutter/…/widgets/framework.dart:4005
E/flutter (14210): #3      Navigator.of
package:flutter/…/widgets/navigator.dart:2727
E/flutter (14210): #4      _PinCodeScreenState.build.<anonymous closure>.<anonymous closure>.<anonymous closure>.<anonymous closure>
package:vista/…/pin_code/pin_code.dart:274
E/flutter (14210): #5      _rootRunUnary (dart:async/zone.dart:1362:47)
E/flutter (14210): #6      _CustomZone.runUnary (dart:async/zone.dart:1265:19)
E/flutter (14210): <asynchronous suspension>

我有以下代码：

Navigator.push(context, MaterialPageRoute(builder: (context) => MyScreen(response: _validatioResponse)));

上面的代码被 RawMaterialButton 小部件调用，onPressed

Answer 1

试试这个方法

 SchedulerBinding.instance.addPostFrameCallback((_) {
                              Navigator.pushNamedAndRemoveUntil(
                                  context, '/', (_) => false);
                            });

未处理的异常：在迁移到空安全之后查找停用的小部件的祖先是不安全的 Navigator.push

Unhandled Exception: Looking up a deactivated widget's ancestor is unsafe Navigator.push after migration to null safety

dart

flutter

dart-null-safety

null-safety