Question

我是新手，我想知道是否可以在一个类的一个参数内添加多个值？

例如，对于参数storePageItemPrice，storePageItemName和storePageImage，我希望能够在每个商店中添加多个价格，商品名称和多个商品图片。

我该如何实现？

示例

class Stores {
String storeName;
String storeImage;
String storeDeliveryTime;
String deliveryCharges;
String storePageImage;
String storePageItemName;
String storePageItemPrice;

Stores.list({this.storeName, this.storeDeliveryTime, 
this.storeImage,this.deliveryCharges,this.storePageImage, 
this.storePageItemName, this.storePageItemPrice});
 }

List<Stores> storesList = [

Stores.list(
storeName: “STORE 1”,
storeImage: "assets/images/STORE1FRONT”,
storeDeliveryTime: "25 min",
deliveryCharges: "£3.90",
storePageImage: “BE ABLE TO ADD MORE THAN ONE IMAGE“ (and then build 
widget.storePageImage),
storePageItemName: “BE ABLE TO ADD MORE THAN ONE ITEM“,(and then 
build widget.storePageItemName),
storePageItemPrice: "BE ABLE TO ADD MORE THAN ONE PRICE”(and then 
build widget.storePageItemPrice),

),

Stores.list(
storeName: “STORE 2”,
storeImage: "assets/images/STORE2FRONT",
storeDeliveryTime: "25 min",
deliveryCharges: "£2.90",
storePageImage: “BE ABLE TO ADD MORE THAN ONE IMAGE“ (and then    
build widget.storePageImage),
storePageItemName: “BE ABLE TO ADD MORE THAN ONE ITEM“,(and then 
build widget.storePageItemName),
storePageItemPrice: "BE ABLE TO ADD MORE THAN ONE PRICE”(and then 
build widget.storePageItemPrice),
),
];

视觉示例；这是主页https://imgur.com/a/0YiMUHj

点击餐厅后，它会导航到餐厅的页面（https://imgur.com/a/KbsIepO），其中添加了多个项目（连接到数据库后可以根据需要添加和删除）

首页代码

ConstrainedBox(
        constraints: BoxConstraints(maxHeight: 1000),
        child: ListView.builder(
          shrinkWrap: true,
          itemCount: storesList.length,
          itemBuilder: (BuildContext context, int index) {
            return Column(
              children: <Widget>[
                GestureDetector(
                    onTap: (){Navigator.of(context).push(new 
MaterialPageRoute(
                        builder: (context) => new StoresPage(
                          storeName: storesList[index].storeName,
                          storeDeliveryTime: 
storesList[index].storeDeliveryTime,
                          deliveryCharges: 
storesList[index].deliveryCharges,
                          storePageImage: 
storesList[index].storePageImage,
                          storePageItemName: 
storesList[index].storePageItemName,
                          storePageItemPrice: 
storesList[index].storePageItemPrice,
                        )));},
                    child: Padding(
                      padding: const EdgeInsets.only(top:5.0),
                      child: Column(
                          children: <Widget>[
                            Container(
                              height: 205,
                              width: 380,
                              child: Image(image: 
AssetImage(storesList[index].storeImage),
                                fit: BoxFit.fill,
                              ),
                            ),
                            Padding(
                              padding: const EdgeInsets.only(left: 
15.0, right: 15.0),
                              child: Row(
                                mainAxisAlignment: 
MainAxisAlignment.spaceBetween,
                                children: <Widget>[
                                Text(storesList[index].storeName),
                                  Row(children: <Widget>[
                                    Icon(Icons.update, size: 20.0),

Text(storesList[index].storeDeliveryTime),
                                  ],
                                  ),
                              ],
                              ),
                            ),
                          ],
                        ),
                    ),
                  ),
              ],
            );
          },
        ),
      ),

导航到商店页面

class StoresPage extends StatefulWidget {
String storeName;
String storeDeliveryTime;
String deliveryCharges;
List<String> storePageImage;
List<String> storePageItemName;
List<String> storePageItemPrice;

StoresPage({
this.storeName, this.storeDeliveryTime, this.deliveryCharges, 
this.storePageImage, this.storePageItemName, this.storePageItemPrice
});

List<Stores> storesList = [
newStore1,
newStore2,
];

此代码无效

SingleChildScrollView(
        child: Column(
          children: <Widget>[
            Row(
              children: <Widget>[
                Padding(
                  padding: EdgeInsets.only(left: 10.0, top: 7.0),
                  child: Container(
                    height: 100,
                    width: 100,
                    decoration: BoxDecoration(
                        borderRadius: BorderRadius.circular(30),
                        image: DecorationImage(fit: BoxFit.fill,image: 
AssetImage(widget.storePageImage()))
                    ),
                  ),
                ),
              ],
            ),
          ],
        ),
      ),

我尝试在商店页面中使用此代码，但没有任何反应

ConstrainedBox(constraints: BoxConstraints(maxHeight: 1000),
        child: ListView.builder(
          shrinkWrap: true,
          itemCount: storesList.length,
          itemBuilder: (BuildContext context, int index){
            return Column(
              children: <Widget>[
                GestureDetector(
                  child: Column(
                    children: <Widget>[
                      Padding(
                        padding: EdgeInsets.only(left: 10.0, top: 7.0),
                        child: Container(
                          height: 100,
                          width: 100,
                          decoration: BoxDecoration(
                              borderRadius: BorderRadius.circular(30),
                              image: DecorationImage(fit: 
BoxFit.fill,image: 
AssetImage(storesList[index].storePageImage.toString()))
                          ),
                        ),
                      ),
                    ],
                  ),
                ),
              ],
            );
          },
        ),
      ),

Answer 1

确保属性输入为列表

class Stores {
  String storeName;
  String storeImage;
  String storeDeliveryTime;
  String deliveryCharges;
  List<String> storePageImage;
  List<String> storePageItemName;
  List<double> storePageItemPrice;

  Stores.list({this.storeName, this.storeDeliveryTime, 
  this.storeImage,this.deliveryCharges,this.storePageImage, 
  this.storePageItemName, this.storePageItemPrice});
}

以后您可以以此创建实例

Stores newStore1 = Stores.list(
  storeName: "STORE 1",
  storeImage: "assets/images/STORE1FRONT",
  storeDeliveryTime: "25 min",
  deliveryCharges: "£2.90",
  storePageImage: ["image1.jpg", "image2.jpg"],
  storePageItemName: ["Apple", "Mango"],
  storePageItemPrice: [100, 200],
);

Stores newStore2 = Stores.list(
  storeName: "STORE 2",
  storeImage: "assets/images/STORE2FRONT",
  storeDeliveryTime: "25 min",
  deliveryCharges: "£2.90",
  storePageImage: ["image1.jpg", "image2.jpg"],
  storePageItemName: ["Apple", "Mango"],
  storePageItemPrice: [100, 200],
);


List<Stores> storesList = [
  newStore1,
  newStore2,
]

如何渲染它？

由于我们需要渲染多张图像，因此我们需要将其所有父图像相乘。

其填充，容器，BoxDecoration，DecorationImage的定义必须多次渲染。

输出

这是我的花朵图像的结果。

* 8月25日更新

这是您最新代码版本的修正

return Scaffold(
  appBar: AppBar(title: Text("Restauran Menus")),
  body: SingleChildScrollView(
    child: Column(
      children: <Widget>[
        Row(
          children: <Widget>[
            for (var storeImage in storePageImage) // loops storePageImage
              Padding(
                padding: EdgeInsets.only(left: 10.0, top: 7.0),
                child: Container(
                  height: 100,
                  width: 100,
                  decoration: BoxDecoration(
                    borderRadius: BorderRadius.circular(30),
                    image: DecorationImage(
                      fit: BoxFit.fill,
                      image: AssetImage(storeImage),
                    ),
                  ),
                ),
              ),
          ],
        ),
      ],
    ),
  ),
);

完整代码

查看此仓库Github

是否可以在一个类的一个参数内添加多个值？

1 个答案:

确保属性输入为列表

以后您可以以此创建实例

如何渲染它？

输出

* 8月25日更新

完整代码

最新演示