ts-universal-events-touch.md

# Touch Event


> **NOTE**<br>
> This event is supported since API version 7. Updates will be marked with a superscript to indicate their earliest API version.


## Required Permissions

None


## Events

| Name | Pop-up | Description |
| -------- | -------- | -------- |
| onTouch(callback: (event?: TouchEvent) =&gt; void) | Yes | Invoked when a touch action is triggered. For details about the event parameters, see [TouchEvent](#touchevent). |


### TouchEvent

- Attributes
  | Name | Type | Description |
  | -------- | -------- | -------- |
  | type | TouchType | Type of a touch event. |
  | touches | Array&lt;TouchObject&gt; | All finger information. |
  | changedTouches | Array&lt;TouchObject&gt; | Finger information changed. |
  | timestamp | number | Timestamp of the event. |
  | target<sup>8+</sup> | [EventTarget](ts-universal-events-click.md) | Target of the event. |

- APIs
  | Name | Description |
  | -------- | -------- |
  | stopPropagation(): void | Pop-up of the stop event. |


- TouchObject
  | Name | Type | Description |
  | -------- | -------- | -------- |
  | type | TouchType | Type of a touch event. |
  | id | number | Unique identifier of a finger. |
  | screenX | number | X coordinate of the touch point relative to the left edge of the screen. |
  | screenY | number | Y coordinate of the touch point relative to the upper edge of the device screen. |
  | x | number | X coordinate of the touch point relative to the left edge of the element to touch. |
  | y | number | Y coordinate of the touch point relative to the upper edge of the element to touch. |


- TouchType
  | Name | Description |
  | -------- | -------- |
  | Down | Trigger a touch event when a finger is pressed. |
  | Up | Trigger a touch event when a finger is lifted. |
  | Move | Trigger a touch event when a finger moves on the screen in pressed state. |
  | Cancel | Trigger an event when a touch event is canceled. |


## Example


```ts
// xxx.ets
@Entry
@Component
struct TouchExample {
  @State text: string = ''
  @State eventType: string = ''

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.SpaceBetween }) {
      Button('Touch').backgroundColor(0x2788D9).height(40).width(80)
        .onTouch((event: TouchEvent) => {
          if (event.type === TouchType.Down) {
            this.eventType = 'Down'
          }
          if (event.type === TouchType.Up) {
            this.eventType = 'Up'
          }
          if (event.type === TouchType.Move) {
            this.eventType = 'Move'
          }
          console.info(this.text = 'TouchType:' + this.eventType + '\nDistance between touch point and touch element:\nx: '
          + event.touches[0].x + '\n' + 'y: ' + event.touches[0].y + '\ncomponent globalPos:('
          + event.target.area.globalPosition.x + ',' + event.target.area.globalPosition.y + ')\nwidth:'
          + event.target.area.width + '\nheight:' + event.target.area.height)
        })
      Text(this.text)
    }.height(200).width(350).padding({ left: 35, right: 35, top: 35 })
  }
}
```

![en-us_image_0000001212058464](figures/en-us_image_0000001212058464.gif)