Flutter 下拉菜单在屏幕中间居中并且只显示几个项目？

Question

目前我正在尝试创建一个位于屏幕右侧的下拉菜单，当您单击它到 select 一个权重时，它将在屏幕中间弹出并且只显示一些权重和 rest它被填充包围，就像这张图片：（就像这张图片）

这就是我在代码中的样子。

太感谢了！

class Weight {
int amount;

Weight(this.amount);

static List<Weight> getWeight() {
return <Weight>[
  Weight(66),
  Weight(67),
  Weight(68),
  Weight(69),
  Weight(70),
  Weight(71),
  Weight(72),
  Weight(73),
  Weight(74),
  Weight(75),
  Weight(76),
];
}

static List<DropdownMenuItem<Weight>> buildDropdownMenuItemsWeight(
  List weightAmount) {
List<DropdownMenuItem<Weight>> items = List();


for (Weight weight in weightAmount) {
  items.add(DropdownMenuItem(
    value: weight,
    child: Text('${weight.amount} Lbs'),
  ));
}
return items;
}


 // Bottom that I'm using on the other page, to reference the above class to display the items in dropdown.
 DropdownButton(
      value: _selectedWeightSystem,
      items: _dropdownMenuItems,
      onChanged: onChangeDropdownItemWeightSystem,
 ),

Answer 1

它已经有 package 来解决您的问题。 使用这个数字选择器。 它还支持 UI 作为您给出的示例