xref: /docs/en/application-dev/reference/apis-arkui/arkui-ts/ts-basic-gestures-pangesture.md

# PanGesture

**PanGesture** is used to trigger a pan gesture when the movement distance of a finger on the screen reaches the minimum value.

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


## APIs

PanGesture(value?: { fingers?: number, direction?: PanDirection, distance?: number } | [PanGestureOptions](#pangestureoptions))

**Atomic service API**: This API can be used in atomic services since API version 11.

**Parameters**

| Name | Type | Mandatory | Description |
| -------- | -------- | -------- | -------- |
| fingers | number | No | Minimum number of fingers to trigger a pan gesture. The value ranges from 1 to 10.<br>Default value: **1**<br>Value range: 1 to 10<br>**NOTE**<br>If the value is less than 1 or is not set, the default value is used. |
| direction | [PanDirection](#pandirection)  | No | Pan direction. The enumerated value supports the AND (&amp;) and OR (\|) operations.<br>Default value: **PanDirection.All** |
| distance | number | No | Minimum pan distance to trigger the gesture, in vp.<br>Default value: **5**<br>**NOTE**<br>If a pan gesture and [tab](ts-container-tabs.md) swipe occur at the same time, set **distance** to **1** so that the gesture can be more easily recognized.<br>If the value specified is less than **0**, the default value **5** is used. |

## PanDirection

Enumerates the pan directions. Unlike **SwipeDirection**, **PanDirection** does not have any angle restrictions.

**Atomic service API**: This API can be used in atomic services since API version 11.

| Name | Description |
| -------- | -------- |
| All | All directions. |
| Horizontal | Horizontal panning. |
| Vertical | Vertical panning. |
| Left | Panning to the left. |
| Right | Panning to the right. |
| Up | Panning up. |
| Down | Panning down. |
| None | Panning disabled. |


## PanGestureOptions

The attributes of the pan gesture recognizer can be dynamically modified using the **PanGestureOptions** API. This avoids modifying attributes through state variables, which will cause a UI re-render.

PanGestureOptions(value?: { fingers?: number, direction?: PanDirection, distance?: number })

**Atomic service API**: This API can be used in atomic services since API version 11.

**Parameters**

| Name | Type                             | Mandatory | Description                                                    |
| --------- | ------------------------------------- | ---- | ------------------------------------------------------------ |
| fingers   | number                                | No  | Minimum number of fingers to trigger a pan gesture. The value ranges from 1 to 10.<br>Default value: **1** |
| direction | [PanDirection](#pandirection)  | No  | Pan direction. The enumerated value supports the AND (&amp;) and OR (\|) operations.<br>Default value: **PanDirection.All** |
| distance  | number                                | No  | Minimum pan distance to trigger the gesture, in vp.<br>Default value: **5**<br>**NOTE**<br>If a pan gesture and [tab](ts-container-tabs.md) swipe occur at the same time, set **distance** to **1** so that the gesture can be more easily recognized.<br>If the value specified is less than **0**, the default value **5** is used.<br>To avoid slow response and lagging during scrolling, set a reasonable pan distance.|

**APIs**

| Name | Description |
| -------- | -------- |
| setDirection(value: [PanDirection](#pandirection))  | Sets the direction.<br>**Atomic service API**: This API can be used in atomic services since API version 11.|
| setDistance(value: number) | Sets the distance.<br>**Atomic service API**: This API can be used in atomic services since API version 11. |
| setFingers(value: number) | Sets the number of fingers.<br>**Atomic service API**: This API can be used in atomic services since API version 11.|
| getDirection()<sup>12+</sup>: [PanDirection](#pandirection) | Obtains the direction.<br>**Atomic service API**: This API can be used in atomic services since API version 12.|


## Events

| Name | Description |
| -------- | -------- |
| onActionStart(event: (event: [GestureEvent](ts-gesture-settings.md#gestureevent)) =&gt; void)  | Invoked when a pan gesture is recognized.<br>**Atomic service API**: This API can be used in atomic services since API version 11.|
| onActionUpdate(event: (event: [GestureEvent](ts-gesture-settings.md#gestureevent)) =&gt; void)  | Invoked when the pan gesture status is updated.<br>If **fingerList** contains multiple fingers, this callback updates the location information of only one finger each time.<br>**Atomic service API**: This API can be used in atomic services since API version 11.|
| onActionEnd(event: (event: [GestureEvent](ts-gesture-settings.md#gestureevent)) =&gt; void)  | Invoked when the finger used for a pan gesture is lifted.<br>**Atomic service API**: This API can be used in atomic services since API version 11.|
| onActionCancel(event: () =&gt; void) | Invoked when a tap cancellation event is received after a pan gesture is recognized.<br>**Atomic service API**: This API can be used in atomic services since API version 11.|

## Attributes

**Atomic service API**: This API can be used in atomic services since API version 11.

| Name | Type   |Description                                       |
| ----  | ------  | ---------------------------------------- |
| tag<sup>11+</sup>   | string  | Tag for the pan gesture. It is used to distinguish the gesture during custom gesture judgment.|

## Example

```ts
// xxx.ets
@Entry
@Component
struct PanGestureExample {
  @State offsetX: number = 0
  @State offsetY: number = 0
  @State positionX: number = 0
  @State positionY: number = 0
  private panOption: PanGestureOptions = new PanGestureOptions({ direction: PanDirection.Left | PanDirection.Right })

  build() {
    Column() {
      Column() {
        Text('PanGesture offset:\nX: ' + this.offsetX + '\n' + 'Y: ' + this.offsetY)
      }
      .height(200)
      .width(300)
      .padding(20)
      .border({ width: 3 })
      .margin(50)
      .translate({ x: this.offsetX, y: this.offsetY, z: 0}) // Move the component with its upper left corner as the coordinate origin.
      // Pan left or right to trigger the gesture event.
      .gesture(
      PanGesture(this.panOption)
        .onActionStart((event: GestureEvent) => {
          console.info('Pan start')
        })
        .onActionUpdate((event: GestureEvent) => {
          if (event) {
            this.offsetX = this.positionX + event.offsetX
            this.offsetY = this.positionY + event.offsetY
          }
        })
        .onActionEnd((event: GestureEvent) => {
          this.positionX = this.offsetX
          this.positionY = this.offsetY
          console.info('Pan end')
        })
      )

      Button ('Set PanGesture Trigger Condition')
        .onClick(() => {
          // Set the pan gesture to be triggered by two fingers moving in any direction.
          this.panOption.setDirection(PanDirection.All)
          this.panOption.setFingers(2)
        })
    }
  }
}
```

**Diagrams**

Panning to the left:

![en-us_image_0000001174264374](figures/en-us_image_0000001174264374.png)  

Click **Set PanGesture Trigger Condition** to set the pan gesture to be triggered by two fingers moving toward the lower left corner.

 ![en-us_image1_0000001174264374](figures/en-us_image1_0000001174264374.png)