如何在CupertinoTabView中使用Flutter Textfield而不会在点击时导致异常？

我正在尝试为iOS创建一个简单的扑动应用程序 .

我的最终目标是让CupertinoTabView在顶部有一个方形图像，下方有一个文本字段，当点击时，它将向上滑动到键盘上方以允许用户输入一些文本 .

当我将“标准”工作代码集成到iOS特定小部件中，并点击文本字段时，我得到一个例外，文本字段不会移动 .

我正在使用以下版本的颤振：

Flutter 0.2.3 • channel beta • https://github.com/flutter/flutter.git
Framework • revision 5a58b36e36 (3 weeks ago) • 2018-03-13 13:20:13 -0700
Engine • revision e61bb9ac3a
Tools • Dart 2.0.0-dev.35.flutter-290c576264

我已经创建了一些代码来演示这个问题 .

这个 working 代码也可以找到here：

import 'package:flutter/material.dart';

void main() => runApp(new MaterialApp(home: new MyHomePage()));

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key}) : super(key: key);

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {

  Widget createTextFieldListView(){
    return new ListView(
      shrinkWrap: true,
      reverse: true,
      children: <Widget>[
        new TextField(
          decoration: new InputDecoration(hintText: "Add text here"),
        ),
        new AspectRatio(
          aspectRatio: 1.0,
          child: new Container(
            color: Colors.green,
          ),
        ),
      ].toList(),
    );
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(title: new Text("textfield")),
      body: createTextFieldListView(),
    );
  }
}

这个 failing iOS代码也可以找到here：

import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';

void main() => runApp(new MaterialApp(home: new MyHomePage()));

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key}) : super(key: key);

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {

  Widget createTextFieldListView(){
    return new ListView(
      shrinkWrap: true,
      reverse: true,
      children: <Widget>[
        new TextField(
          decoration: new InputDecoration(hintText: "Add text here"),
        ),
        new AspectRatio(
          aspectRatio: 1.0,
          child: new Container(
            color: Colors.green,
          ),
        ),
      ].toList(),
    );
  }

  @override
  Widget build(BuildContext context) {
    return new CupertinoTabScaffold(
      tabBar: new CupertinoTabBar(
        items: <BottomNavigationBarItem>[
          new BottomNavigationBarItem(icon: new Icon(Icons.home), title: new Text("One")),
          new BottomNavigationBarItem(icon: new Icon(Icons.home), title: new Text("Two")),
          new BottomNavigationBarItem(icon: new Icon(Icons.home), title: new Text("Three")),
        ],
      ),
      tabBuilder: (BuildContext context, int index) {
        return new CupertinoTabView(builder: (BuildContext context){
          return new CupertinoPageScaffold(
            navigationBar: new CupertinoNavigationBar(),
            child: createTextFieldListView(),
          );
        });
      },
    );
  }
}

此 exception 消息也可以找到here

Launching lib/main.dart on iPhone in debug mode...
Signing iOS app for device deployment using developer identity: "<removed>"
Running Xcode clean...
Starting Xcode build...
Xcode build done
Installing and launching...
Syncing files to device iPhone...
══╡ EXCEPTION CAUGHT BY GESTURE ╞═══════════════════════════════════════════════════════════════════
The following assertion was thrown while handling a gesture:
'package:flutter/src/material/ink_well.dart': Failed assertion: line 41: 'controller != null': is
not true.

Either the assertion indicates an error in the framework itself, or we should provide substantially
more information in this error message to help you determine and fix the underlying cause.
In either case, please report this assertion by filing a bug on GitHub:
  https://github.com/flutter/flutter/issues/new

When the exception was thrown, this was the stack:
#2      new InteractiveInkFeature (package:flutter/src/material/ink_well.dart:41)
#3      new InkSplash (package:flutter/src/material/ink_splash.dart:130)
#4      _InkSplashFactory.create (package:flutter/src/material/ink_splash.dart:61)
#5      _TextFieldState._createInkFeature (package:flutter/src/material/text_field.dart:366)
#6      _TextFieldState._startSplash (package:flutter/src/material/text_field.dart:405)
#7      _TextFieldState._handleTapDown (package:flutter/src/material/text_field.dart:384)
#8      TapGestureRecognizer._checkDown.<anonymous closure> (package:flutter/src/gestures/tap.dart:142)
#9      GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:102)
#10     TapGestureRecognizer._checkDown (package:flutter/src/gestures/tap.dart:142)
#11     TapGestureRecognizer.acceptGesture (package:flutter/src/gestures/tap.dart:121)
#12     GestureArenaManager.sweep (package:flutter/src/gestures/arena.dart:156)
#13     BindingBase&GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:147)
#14     BindingBase&GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:121)
#15     BindingBase&GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:101)
#16     BindingBase&GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:64)
#17     BindingBase&GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:48)
#18     _invoke1 (file:///Users/errolc/code/flutter/bin/cache/pkg/sky_engine/lib/ui/hooks.dart:134)
#19     _dispatchPointerDataPacket (file:///Users/errolc/code/flutter/bin/cache/pkg/sky_engine/lib/ui/hooks.dart:91)
(elided 2 frames from class _AssertionError)

Handler: onTapDown
Recognizer:
  TapGestureRecognizer#ddee3(debugOwner: GestureDetector, state: ready, finalPosition: Offset(80.0,
  402.0))
════════════════════════════════════════════════════════════════════════════════════════════════════