ts-basic-components-navigation.md

# Navigation

The **\<Navigation>** component typically functions as the root container of a page and displays the page title, toolbar, and menu based on the attribute settings.

> **NOTE**
>
> This component is supported since API version 8. Updates will be marked with a superscript to indicate their earliest API version.


## Child Components

Supported


## APIs

Navigation()

Creates a component that can automatically display the navigation bar, title, and toolbar based on the attribute settings.

## Attributes

In addition to the [universal attributes](ts-universal-attributes-size.md), the following attributes are supported.

| Name            | Type                                    | Description                                      |
| -------------- | ---------------------------------------- | ---------------------------------------- |
| title          | string \| [CustomBuilder](ts-types.md#custombuilder8)<sup>8+</sup> | Page title.                                   |
| subTitle       | string                                   | Subtitle of the page.                                  |
| menus          | Array<NavigationMenuItem&gt; \| [CustomBuilder](ts-types.md#custombuilder8)<sup>8+</sup> | Menu in the upper right corner of the page.     |
| titleMode      | NavigationTitleMode                      | Display mode of the page title bar.<br>Default value: **NavigationTitleMode.Free**|
| toolBar        | object \| [CustomBuilder](ts-types.md#custombuilder8)<sup>8+</sup> | Content of the toolbar.<br>**items**: all items on the toolbar.    |
| hideToolBar    | boolean                                  | Whether to hide the toolbar.<br>Default value: **false**<br>**true**: Hide the toolbar.<br>**false**: Show the toolbar.|
| hideTitleBar   | boolean                                  | Whether to hide the title bar.<br>Default value: **false**                    |
| hideBackButton | boolean                                  | Whether to hide the back button.<br>Default value: **false**                    |

## NavigationMenuItem

| Name  | Type                   | Mandatory| Description                          |
| ------ | ----------------------- | ---- | ------------------------------ |
| value  | string                  | Yes  | Text of a menu item.    |
| icon   | string                  | No  | Icon path of a menu item.|
| action | () =&gt; void | No  | Callback invoked when a menu item is selected.    |

## object

| Name  | Type                   | Mandatory| Description                          |
| ------ | ----------------------- | ---- | ------------------------------ |
| value  | string                  | Yes  | Text of an option on the toolbar.    |
| icon   | string                  | No  | Icon path of an option on the toolbar.|
| action | () =&gt; void | No  | Callback invoked when an option is selected.    |

## NavigationTitleMode

| Name  | Description                                      |
| ---- | ---------------------------------------- |
| Free | When the content is a scrollable component, the main title shrinks as the content scrolls down (the subtitle fades out with its size remaining unchanged) and restores when the content scrolls up to the top.|
| Mini | The icon, main title, and subtitle are in mini mode.                      |
| Full | The main title and subtitle are in full mode.                         |

>  **NOTE**
>
>  Currently, the scrollable component can only be **\<List>**.


## Events

| Name                                      | Description                                    |
| ---------------------------------------- | ---------------------------------------- |
| onTitleModeChange(callback: (titleMode: NavigationTitleMode) =&gt; void) | Triggered when **titleMode** is set to **NavigationTitleMode.Free** and the title bar mode changes as content scrolls.|


## Example

```ts
// xxx.ets
@Entry
@Component
struct NavigationExample {
  private arr: number[] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
  @State hideBar: boolean = true

  @Builder NavigationTitle() {
    Column() {
      Text('title')
        .width(80)
        .height(60)
        .fontColor(Color.Blue)
        .fontSize(30)
    }
    .onClick(() => {
      console.log("title")
    })
  }

  @Builder NavigationMenus() {
    Row() {
      Image('images/add.png')
        .width(25)
        .height(25)
      Image('comment/more.png')
        .width(25)
        .height(25)
        .margin({ left: 30 })
    }.width(100)
  }

  build() {
    Column() {
      Navigation() {
        Search({ value: '', placeholder: "" }).width('85%').margin(26)
        List({ space: 5, initialIndex: 0 }) {
          ForEach(this.arr, (item) => {
            ListItem() {
              Text('' + item)
                .width('90%')
                .height(80)
                .backgroundColor('#3366CC')
                .borderRadius(15)
                .fontSize(16)
                .textAlign(TextAlign.Center)
            }.editable(true)
          }, item => item)
        }
        .listDirection(Axis.Vertical)
        .height(300)
        .margin({ top: 10, left: 18 })
        .width('100%')

        Button(this.hideBar ? "tool bar" : "hide bar")
          .onClick(() => {
            this.hideBar = !this.hideBar
          })
          .margin({ left: 135, top: 60 })
      }
      .title(this.NavigationTitle)
      .subTitle('subtitle')
      .menus(this.NavigationMenus)
      .titleMode(NavigationTitleMode.Free)
      .hideTitleBar(false)
      .hideBackButton(false)
      .onTitleModeChange((titleModel: NavigationTitleMode) => {
        console.log('titleMode')
      })
      .toolBar({ items: [
        { value: 'app', icon: 'images/grid.svg', action: () => {
          console.log("app")
        } },
        { value: 'add', icon: 'images/add.svg', action: () => {
          console.log("add")
        } },
        { value: 'collect', icon: 'images/collect.svg', action: () => {
          console.log("collect")
        } }] })
      .hideToolBar(this.hideBar)
    }
  }
}
```

![en-us_image_0000001256978359](figures/en-us_image_0000001256978359.gif)

```ts
// xxx.ets
@Entry
@Component
struct ToolbarBuilderExample {
  @State currentIndex: number = 0
  @State Build: Array<Object> = [
    {
      icon: $r('app.media.ic_public_add'),
      icon_after: $r('app.media.ic_public_addcolor'),
      text: 'add',
      num: 0
    },
    {
      icon: $r('app.media.ic_public_app'),
      icon_after: $r('app.media.ic_public_appcolor'),
      text: 'app',
      num: 1
    },
    {
      icon: $r('app.media.ic_public_collect'),
      icon_after: $r('app.media.ic_public_collectcolor'),
      text: 'collect',
      num: 2
    }
  ]

  @Builder NavigationToolbar() {
    Row() {
      ForEach(this.Build, item => {
        Column() {
          Image(this.currentIndex == item.num ? item.icon_after : item.icon)
            .width(25)
            .height(25)
          Text(item.text)
            .fontColor(this.currentIndex == item.num ? "#ff7500" : "#000000")
        }
        .onClick(() => {
          this.currentIndex = item.num
        })
        .margin({ left: 70 })
      })
    }
  }

  build() {
    Column() {
      Navigation() {
        Flex() {
        }
      }
      .toolBar(this.NavigationToolbar)
    }
  }
}
```

![en-us_image_0000001212058484](figures/en-us_image_0000001212058484.gif)