为了禁用任何按钮，如FlatButton, RaisedButton, MaterialButton, IconButton等，你需要做的就是将onPressed和onLongPress属性设置为null。下面是一些按钮的简单示例:

FlatButton (Enabled)

FlatButton(
  onPressed: (){}, 
  onLongPress: null, // Set one as NOT null is enough to enable the button
  textColor: Colors.black,
  disabledColor: Colors.orange,
  disabledTextColor: Colors.white,
  child: Text('Flat Button'),
),

FlatButton(禁用)

FlatButton(
  onPressed: null,
  onLongPress: null,
  textColor: Colors.black,
  disabledColor: Colors.orange,
  disabledTextColor: Colors.white,
  child: Text('Flat Button'),
),

RaisedButton(启用)

RaisedButton(
  onPressed: (){},
  onLongPress: null, // Set one as NOT null is enough to enable the button
  // For when the button is enabled
  color: Colors.lightBlueAccent,
  textColor: Colors.black,
  splashColor: Colors.blue,
  elevation: 8.0,

  // For when the button is disabled
  disabledTextColor: Colors.white,
  disabledColor: Colors.orange,
  disabledElevation: 0.0,

  child: Text('Raised Button'),
),

RaisedButton(禁用)

RaisedButton(
  onPressed: null,
  onLongPress: null,
  // For when the button is enabled
  color: Colors.lightBlueAccent,
  textColor: Colors.black,
  splashColor: Colors.blue,
  elevation: 8.0,

  // For when the button is disabled
  disabledTextColor: Colors.white,
  disabledColor: Colors.orange,
  disabledElevation: 0.0,

  child: Text('Raised Button'),
),

IconButton (Enabled)

IconButton(
  onPressed: () {},
  icon: Icon(Icons.card_giftcard_rounded),
  color: Colors.lightBlueAccent,
            
  disabledColor: Colors.orange,
),

IconButton(禁用)

IconButton(
  onPressed: null,
  icon: Icon(Icons.card_giftcard_rounded),
  color: Colors.lightBlueAccent,
            
  disabledColor: Colors.orange,
),

注意:一些按钮，如IconButton只有onPressed属性。

我认为您可能需要引入一些帮助函数来构建按钮，以及一个有状态的小部件以及一些要关闭的属性。

Use a StatefulWidget/State and create a variable to hold your condition (e.g. isButtonDisabled) Set this to true initially (if that's what you desire) When rendering the button, don't directly set the onPressed value to either null or some function onPressed: () {} Instead, conditionally set it using a ternary or a helper function (example below) Check the isButtonDisabled as part of this conditional and return either null or some function. When the button is pressed (or whenever you want to disable the button) use setState(() => isButtonDisabled = true) to flip the conditional variable. Flutter will call the build() method again with the new state and the button will be rendered with a null press handler and be disabled.

这里是一些更多的上下文使用颤振计数器项目。

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  bool _isButtonDisabled;

  @override
  void initState() {
    _isButtonDisabled = false;
  }

  void _incrementCounter() {
    setState(() {
      _isButtonDisabled = true;
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text("The App"),
      ),
      body: new Center(
        child: new Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            new Text(
              'You have pushed the button this many times:',
            ),
            new Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
            _buildCounterButton(),
          ],
        ),
      ),
    );
  }

  Widget _buildCounterButton() {
    return new RaisedButton(
      child: new Text(
        _isButtonDisabled ? "Hold on..." : "Increment"
      ),
      onPressed: _isButtonDisabled ? null : _incrementCounter,
    );
  }
}

在这个例子中，我使用了一个内联三元来有条件地设置Text和onPressed，但它可能更适合你将其提取到一个函数中(你也可以使用相同的方法来更改按钮的文本):

Widget _buildCounterButton() {
    return new RaisedButton(
      child: new Text(
        _isButtonDisabled ? "Hold on..." : "Increment"
      ),
      onPressed: _counterButtonPress(),
    );
  }

  Function _counterButtonPress() {
    if (_isButtonDisabled) {
      return null;
    } else {
      return () {
        // do anything else you may want to here
        _incrementCounter();
      };
    }
  }

见下面的可能的解决方案，添加'ValueListenableBuilder'的'TextEditingValue'监听控制器(TextEditingController)，并返回你的函数调用如果控制器。文本不为空，如果为空则返回'null'。

// valuelistenablebuilder环绕按钮

  ValueListenableBuilder<TextEditingValue>(
                  valueListenable: textFieldController,
                  builder: (context, ctrl, __) => ElevatedButton(                    
                    onPressed: ctrl.text.isNotEmpty ? yourFunctionCall : null,
                    child: Text(
                      'SUBMIT',
                      style: GoogleFonts.roboto(fontSize: 20.0),
                    ),
                  ),
                ),

特克斯菲尔德

 TextField(controller: textFieldController,
                 onChanged: (newValue) {
                  textFieldText = newValue;
                },
              ),

生成器将监听控制器，并仅在使用文本字段时启用按钮。我希望这能回答问题。让我知道…

根据文件:

如果onPressed回调为空，则该按钮将被禁用 默认情况下类似于disabledColor中的平面按钮。

所以，你可以这样做:

RaisedButton(
  onPressed: calculateWhetherDisabledReturnsBool() ? null : () => whatToDoOnPressed,
  child: Text('Button text')
);

在我看来，这是最简单的方法:

RaisedButton(
  child: Text("PRESS BUTTON"),
  onPressed: booleanCondition
    ? () => myTapCallback()
    : null
)

你也可以使用吸收指针，你可以用下面的方式使用它:

AbsorbPointer(
      absorbing: true, // by default is true
      child: RaisedButton(
        onPressed: (){
          print('pending to implement onPressed function');
        },
        child: Text("Button Click!!!"),
      ),
    ),

如果您想了解有关此小部件的更多信息，可以查看以下链接Flutter Docs