RenderFlex在底部溢出了40个像素，而我正在使用带有新列的尾随

Question

我使用带新列的尾随在购物车中上下放置两个箭头。我在做这件事时遇到了一个问题。我会发布我的代码

导入‘package:flutter/material.dart’；

class Cart_products extends StatefulWidget {
@override
_Cart_productsState createState() => _Cart_productsState();
}
class _Cart_productsState extends State<Cart_products> {
var products_on_the_carts = [
{
"name": "Blazer",
"picture": "images/products/blazer.jpg",
"price": 80,
"size": "M",
"color": "black",
"quantity": 1,
},
{
"name": "Shoes",
"picture": "images/products/hills1.jpeg",
"price": 100,
"size": "38",
"color": "red",
"quantity": 1,
},
];
@override
Widget build(BuildContext context) {
return new ListView.builder(
itemCount: products_on_the_carts.length,
itemBuilder: (context, index) {
return new Single_cart_products(
cart_product_name: products_on_the_carts[index]["name"],
cart_product_color: products_on_the_carts[index]["color"],
cart_product_quantity: products_on_the_carts[index]["quantity"],
cart_product_size: products_on_the_carts[index]["size"],
cart_product_price: products_on_the_carts[index]["price"],
cart_product_picture: products_on_the_carts[index]["picture"],
);
});
}
}
class Single_cart_products extends StatelessWidget {
final cart_product_name;
final cart_product_picture;
final cart_product_price;
final cart_product_size;
final cart_product_color;
final cart_product_quantity;
Single_cart_products({
this.cart_product_name,
this.cart_product_picture,
this.cart_product_price,
this.cart_product_size,
this.cart_product_color,
this.cart_product_quantity
});
@override
Widget build(BuildContext context) {
return Card(
child: ListTile(
leading: new Image.asset(cart_product_picture),
title: new Text(cart_product_name),
subtitle: new Column(
children: <Widget>[
new Row(
children: <Widget>[
// product size
Padding(
padding: const EdgeInsets.all(0.0),
child: new Text("Size:"),
),
Padding(
padding: const EdgeInsets.all(0.0),
child: new Text(cart_product_size, style: TextStyle(color:Colors.red),),
),
// product color
new Padding(padding: const EdgeInsets.fromLTRB(20.0, 8.0, 8.0, 8.0),
child: new Text("Color:"),),
Padding(
padding: const EdgeInsets.all(0.0),
child: new Text(cart_product_color, style: TextStyle(color:Colors.red),),
),
],
),
// product price
new Container(
alignment: Alignment.topLeft,
child: new Text("$${cart_product_price}", style: TextStyle(fontSize: 16.0, fontWeight: FontWeight.bold, color:

Colors.red(、(，)]，)，拖尾：新建列(儿童：[新图标按钮(icon:icon(Icons.arrow_drop_up(，onPressed:((｛｝(，//新文本("$cart_product_size"(，新图标按钮(icon:icon(Icons.arrow_drop_down(，onPressed:((｛｝(，]，)，)，)；}}

Answer 1

trailing: Column(
mainAxisAlignment: MainAxisAlignment.start,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Expanded(
child: IconButton(
padding: EdgeInsets.zero,
icon: Icon(Icons.arrow_drop_up),
onPressed: () {},
),
),
Expanded(child: Text("$cart_prod_qty")),
Expanded(
child: IconButton(
padding: EdgeInsets.zero,
icon: Icon(Icons.arrow_drop_down),
onPressed: () {},
),
),
],
),