Building a Food Category List Layout

Use the <List> component and ForEach loop to build the food category list layout.

1. Create a page file named FoodCategoryList.ets in the pages directory and rename the index.ets file FoodDetail.ets.

2. Create a <List> component named FoodList as the page entry point. Then, add a <ListItem> component named FoodListItem as its child component. The <List> component is used to display data of the same type. Its child component <ListItem> is used to display specific items in the list. “`ts @Component struct FoodListItem { build() {} }

@Entry @Component struct FoodList { build() { List() { ListItem() { FoodListItem() } } } }

3. Import the **FoodData** class and **initializeOnStartup** method.

There are two file access methods in application code:
- Use a relative path to reference the code file: Use **"../"** for referencing the parent directory and **"./"** (which can also be omitted) for referencing the current directory.
- Use the absolute path, which is the root path of the current module, to reference the code file, for example, **common/utils/utils**.
In this example, a relative path is used for access.

import { FoodData } from ‘../model/FoodData’ import { initializeOnStartup } from ‘../model/FoodDataModels’

4. Configure the **FoodList** and **FoodListItem** components to pass values. Create a member variable named **foodItems** of the **FoodData[]** type in the **FoodList** component and invoke the **initializeOnStartup** method to assign a value to the variable. Create a member variable **foodItem** of the **FoodData** type in the **FoodListItem** component. Pass the **foodItems[0]** of the first element in the parent **foodItems** array as a parameter to **FoodListItem**.
   ```ts
   import { FoodData } from '../model/FoodData'
   import { initializeOnStartup } from '../model/FoodDataModels'

   @Component
   struct FoodListItem {
     private foodItem: FoodData
     build() {}
   }

   @Entry
   @Component
   struct FoodList {
     private foodItems: FoodData[] = initializeOnStartup()
     build() {
       List() {
         ListItem() {
           FoodListItem({ foodItem: this.foodItems[0] })
         }
       }
     }
   }

1. Declare the UI layout of the FoodListItem child component. Create a <Flex> component, including the food image thumbnail, food name, and calories in the food. “`ts import { FoodData } from ‘../model/FoodData’ import { initializeOnStartup } from ‘../model/FoodDataModels’

   @Component struct FoodListItem { private foodItem: FoodData build() { Flex({ justifyContent: FlexAlign.Start, alignItems: ItemAlign.Center }) { Image(this.foodItem.image) .objectFit(ImageFit.Contain) .height(40) .width(40) .margin({ right: 16 }) Text(this.foodItem.name) .fontSize(14) .flexGrow(1) Text(this.foodItem.calories + ‘ kcal’) .fontSize(14) } .height(64) .margin({ right: 24, left:32 }) } }

@Entry @Component struct FoodList { private foodItems: FoodData[] = initializeOnStartup() build() { List() { ListItem() { FoodListItem({ foodItem: this.foodItems[0] }) } } } }

   
   
   ![en-us_image_0000001204776353](figures/en-us_image_0000001204776353.png)
   
6. Create two **FoodListItem** objects. Create two **FoodListItem** objects in the **List** component and pass the first element **this.foodItems[0]** and the second element **foodItem: this.foodItems[1]** to the **FoodListItem**.

   ```ts
   import { FoodData } from '../model/FoodData'
   import { initializeOnStartup } from '../model/FoodDataModels'
   
   @Component
   struct FoodListItem {
     private foodItem: FoodData
   
     build() {
       Flex({ justifyContent: FlexAlign.Start, alignItems: ItemAlign.Center }) {
         Image(this.foodItem.image)
           .objectFit(ImageFit.Contain)
           .height(40)
           .width(40)
           .margin({ right: 16 })
         Text(this.foodItem.name)
           .fontSize(14)
           .flexGrow(1)
         Text(this.foodItem.calories + ' kcal')
           .fontSize(14)
       }
       .height(64)
       .margin({ right: 24, left: 32 })
     }
   }
   
   @Entry
   @Component
   struct FoodList {
     private foodItems: FoodData[] = initializeOnStartup()
   
     build() {
       List() {
         ListItem() {
           FoodListItem({ foodItem: this.foodItems[0] })
         }
   
         ListItem() {
           FoodListItem({ foodItem: this.foodItems[1] })
         }
       }
     }
   }

  ![en-us_image1_0000001204776353](figures/en-us_image1_0000001204776353.png)

1. Import ForEach so that you do not need to create FoodListItem objects one by one.

   import { FoodData } from '../model/FoodData'
   import { initializeOnStartup } from '../model/FoodDataModels'
   
   @Component
   struct FoodListItem {
     private foodItem: FoodData
     build() {
       Flex({ justifyContent: FlexAlign.Start, alignItems: ItemAlign.Center }) {
         Image(this.foodItem.image)
           .objectFit(ImageFit.Contain)
           .height(40)
           .width(40)     
           .margin({ right: 16 })
         Text(this.foodItem.name)
           .fontSize(14)
           .flexGrow(1)
         Text(this.foodItem.calories + ' kcal')
           .fontSize(14)
       }
       .height(64)
       .margin({ right: 24, left:32 })
     }
   }
   
   @Entry
   @Component
   struct FoodList {
     private foodItems: FoodData[] = initializeOnStartup()
     build() {
       List() {
         ForEach(this.foodItems, item => {
           ListItem() {
             FoodListItem({ foodItem: item })
           }
         }, item => item.id.toString())
       }
     }
   }

1. Add a title for the FoodList.

   @Entry
   @Component
   struct FoodList {
     private foodItems: FoodData[] = initializeOnStartup()
   
     build() {
       Column() {
         Flex({ justifyContent: FlexAlign.Start, alignItems: ItemAlign.Center }) {
           Text('Food List')
             .fontSize(20)
             .margin({ left: 20 })
         }
         .height('7%')
         .backgroundColor('#FFf1f3f5')
   
         List() {
           ForEach(this.foodItems, item => {
             ListItem() {
               FoodListItem({ foodItem: item })
             }
           }, item => item.id.toString())
         }
         .height('93%')
       }
     }
   }

 ![en-us_image_0000001169678922](figures/en-us_image_0000001169678922.png)

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