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Flutter 选择该选项时,颤振下拉按钮显示标签_Flutter - Fatal编程技术网

Flutter 选择该选项时,颤振下拉按钮显示标签

Flutter 选择该选项时,颤振下拉按钮显示标签,flutter,Flutter,是否可以使用下拉按钮: return DropdownButton<String>( items: <String>['Foo', 'Bar'].map((String value) { return new DropdownMenuItem<String>( value: value, child: new Text(value),

是否可以使用
下拉按钮

 return DropdownButton<String>(
          items: <String>['Foo', 'Bar'].map((String value) {
            return new DropdownMenuItem<String>(
              value: value,
              child: new Text(value),
            );
          }).toList(),
          onChanged: (_) {},
        );
当在上述文本表单字段中写入内容时,会显示单词
Input
。像这样:


将DropdownButton替换为DropdownButton表单字段:


将DropdownButton更改为DropdownButtonFormField并添加此装饰

              decoration: InputDecoration(
                filled: true,
                fillColor: Hexcolor('#ecedec'),
                labelText: 'Occupation',
                border: new CustomBorderTextFieldSkin().getSkin(),
              ),

DropdownButtonFormField
DropdownButton
不同,它在点击时有填充物,不会触发下拉,因此如果你点击的不是中心,那么什么都不会发生,你坐在那里猜测它为什么不起作用。。如何使其可点击?@temirbek刚刚将“isExpanded”设置为true@MostafaSoliman那没用。我用
materialTargetSize:materialTargetSize:materialTargetSize将DBFF包装到
ButtonTheme
中解决了这个问题。填充的
参数谢谢亲爱的,工作起来很有魅力:)印象深刻,推荐这个答案
              decoration: InputDecoration(
                filled: true,
                fillColor: Hexcolor('#ecedec'),
                labelText: 'Occupation',
                border: new CustomBorderTextFieldSkin().getSkin(),
              ),