调用 Navigator.of(context).pop() 后如何获取父上下文？

Question

How to get the correct context after calling Navigator.of(context).pop() ?

Example:

ElevatedButton(
  child: Text('Test'),
  onPressed: () {
    Navigator.of(context).pop();
    showLoadingDialog(context);
  })

The showLoadingDialog is basically a wrap of showDialog call which requires a context . But in my understanding the context is changed for calling Navigator.of(context).pop() . The reason I need to call pop() is because this ElevatedButton is on a SimpleDialog , and it needs to be closed by calling pop() .

During test, this example gives errors:

E/flutter ( 6989): [ERROR:flutter/lib/ui/ui_dart_state.cc(177)] Unhandled Exception: Looking up a deactivated widget's ancestor is unsafe.
E/flutter ( 6989): At this point the state of the widget's element tree is no longer stable.
E/flutter ( 6989): 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.

After reading some docs and using them in my project, I still can't fully understand context. Any help is appreciated, thanks!

Answer 1

What you have to remember is that the views are placed in a stack. So when you call Navigator.of(context).pop(), it removes your current view and gets you to the previous one. Try wrapping the navigator on a widget and that might solve your issue.

Answer 2

I solved it in my own case: Because showDialog needs a builder which makes a new context . Give it a different name for example 'contextOfDialog', change the above codes to

ElevatedButton(
  child: Text('Test'),
  onPressed: () {
    Navigator.of(contextOfDialog).pop();
    showLoadingDialog(context);
  })

And this will work properly. Since the context is the proper one after pop() is called.

My solution essentially is passing the parent context as parameter. However the question still remains: when you only have the access to the current context , how to get the parent context after pop() ?