Flutter 通过在Flatter应用程序中应用主题数据，Appbar颜色、工具栏颜色、文本、字体和按钮不会改变

例如，若要在按钮上应用主题，我正在执行此操作，但主题在按钮上不起作用

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Personal Expenses',
      theme: ThemeData(
    
        brightness: Brightness.light,
        primaryColor: Colors.lightGreen[800],
        primarySwatch: Colors.amber,
        errorColor: Colors.red,
        accentColor: Colors.cyan[600],
        fontFamily: 'Quicksand',
        textTheme: ThemeData.light().textTheme.copyWith(
            title: TextStyle(
              fontFamily: 'Quicksand',
              backgroundColor: Colors.grey,
              fontSize: 18,
            ),
        ),
        appBarTheme: AppBarTheme(
          textTheme: ThemeData.light().textTheme.copyWith(
              title: TextStyle(
                  fontFamily: 'OpenSans',
                  fontSize: 20,
                  fontWeight: FontWeight.bold,
                  fontStyle: FontStyle.italic),
                  button: TextStyle(color: Colors.white),
              ),
          )
        ),
        home: MyHomePage(),
    );
  }

---

您可以在

AppBarTheme

下设置按钮文本颜色，而不是在

textTheme

中设置按钮文本颜色，您可以在

FlatButton

中引用该主题

这可能会解决你的问题

FlatButton(
  color: Colors.white,
  textColor: Theme.of(context).textTheme.button.color,
  onPressed: _presentDatePicker,
  child: Text(
    'Choose Date',
    style: TextStyle(fontWeight: FontWeight.bold),
  ),
)

或者你可以像这样设置按钮颜色

FlatButton(
  color: Colors.white,
  textColor: Theme.of(context).AppBarTheme.textTheme.button.color,
  onPressed: _presentDatePicker,
  child: Text(
    'Choose Date',
    style: TextStyle(fontWeight: FontWeight.bold),
  ),
)

theme: ThemeData(
    primarySwatch: Colors.purple,
    accentColor: Colors.amber,
    buttonColor: Colors.white,
),

在

平面按钮中使用该按钮颜色，如下所示

FlatButton(
  color: Colors.white,
  textColor: Theme.of(context).AppBarTheme.textTheme.button.color,
  onPressed: _presentDatePicker,
  child: Text(
    'Choose Date',
    style: TextStyle(fontWeight: FontWeight.bold),
  ),
)

theme: ThemeData(
    primarySwatch: Colors.purple,
    accentColor: Colors.amber,
    buttonColor: Colors.white,
),