无法导航到 flutter 中的主页

Question

I have an app comprising of home and update screens.

I am unable to navigate back to the home screen from the update screen.

See below code for home screen

  // build the list widget
  Widget _buildTaskWidget(task) {
    return ListTile(
      leading: Icon(Icons.assignment),
      title: Text(task['name']),
      subtitle: Text(task['created_at']),
      onTap: () {
        Navigator.push(
          context,
          MaterialPageRoute(
            builder: (context) => UpdateTask(task: task),
          ),
        );
      }
    );
  }

See below code for the update screen

@override
      Widget build(BuildContext context) {
        // final Task task = ModalRoute.of(context).settings.arguments;
        return Scaffold(
          resizeToAvoidBottomInset: true,
          appBar: AppBar(
            title: Text('Update Task'),
          ),
          body: ListView(
            children: <Widget>[
              inputWidget(),
              inputWidgetForVendor(),
              inputWidgetForAmount(),
              Container(
                margin: EdgeInsets.fromLTRB(45, 1, 45, 1),
                child: RaisedButton(
                  color: Colors.blueAccent,
                  child: Text('Update Task', style: TextStyle(color: Colors.white)),
                  onPressed: () async {
                     var res = await updateNewTask(_taskTextInput.text, _vendorTextInput.text,  _amountTextInput.text, id);
                     print(res);
                      Navigator.pop(context);
                  },
                ),
              )
            ],
          )// This trailing comma makes auto-formatting nicer for build methods.
        );
      }

If I remove the current onPressed function and replace with this below, it works

onPressed: () { Navigator.pop(context); },

What am I doing wrong in the initial function? The update function successfully updates the list items, however I am unable to navigate back. See below error logs:

E/flutter (27123): [ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List<dynamic>'
E/flutter (27123): #0      updateNewTask (package:task/repository/services.dart:67:10)
E/flutter (27123): <asynchronous suspension>

Please help.

Answer 1

Maybe outsourcing your async update function is a simple solution at this point, when you want to instantly go back to your home screen. You could print the update directly in the function then.

Just leave onpressed() as it is.

onPressed: () {
  updateNewTask(_taskTextInput.text, _vendorTextInput.text,  _amountTextInput.text, id);
  Navigator.pop(context);
},