Flutter_typehead：BoxConstraints不对RecommendationsBoxDecoration应用maxWidth

Question

我正在使用此软件包：https://pub.dartlang.org/packages/flutter_typeahead。 我正在尝试使用BoxConstraints来限制建议的框宽大小，但这是行不通的。 这是我的代码：

 return TypeAheadFormField(
    textFieldConfiguration: TextFieldConfiguration(
      controller: _typeAheadController,
      decoration: InputDecoration(
          prefixIcon: _icon,
          hintText: _hintText),
    ),
    suggestionsCallback: (String pattern) async {
      return suggestions;
    },
    itemBuilder: (context, suggestion) {
      if (suggestions.isNotEmpty)
            ListTile(
              title: Text(suggestion),
            );
    },suggestionsBoxDecoration: SuggestionsBoxDecoration(
    constraints: BoxConstraints(maxWidth: 10, maxHeight: 10)
  ),
    onSuggestionSelected: (suggestion) {
      this._typeAheadController.text = suggestion;
    },
    hideOnEmpty: true,
  );

对高度的约束有效，但对宽度的约束无效。