User scrolled

This event tracks when a user scrolls the content. Here, "scroll" is a general term that covers any scrolling interaction, whether it's a mouse wheel, a swipe on a touchscreen, or a keyboard shortcut.

Automatically tracked

The SDK automatically tracks this event when a user scrolls the content.

Input properties

This event has no input properties.

Processed properties

These properties are automatically tracked:

start(optional)

object

The scroll offset at the beginning of the gesture, in pixels.

This is the distance from the top-left corner of the surface to the top-left corner of the viewport. For example, if the user has scrolled 500 pixels down, y is 500.

Maximum scroll value

Even when the user scrolls to the very bottom, y does not equal the surface height. That is because y tracks the top edge of the viewport, not the bottom edge. The maximum value of y is surfaceSize.height - viewportSize.height.

x

number

The horizontal offset from the left edge of the surface, in pixels.

y

number

The vertical offset from the top edge of the surface, in pixels.

end

object

The scroll offset at the end of the gesture, in pixels.

This is the distance from the top-left corner of the surface to the top-left corner of the viewport. For example, if the user scrolled to 780 pixels down, y is 780.

Maximum scroll value

Even when the user scrolls to the very bottom, y does not equal the surface height. That is because y tracks the top edge of the viewport, not the bottom edge. The maximum value of y is surfaceSize.height - viewportSize.height.

x

number

The horizontal offset from the left edge of the surface, in pixels.

y

number

The vertical offset from the top edge of the surface, in pixels.

surfaceSize(optional)

object

The total dimensions of the scrollable surface, in pixels.

This represents the entire scrollable area, not just the visible portion. For example, on a web page, this would be the full document size, including content below the fold. In a mobile app, it would be the entire scrollable screen area.

width

number

The total width of the surface, in pixels.

height

number

The total height of the surface, in pixels.

viewportSize(optional)

object

The dimensions of the visible area, in pixels.

This is the portion of the surface currently visible to the user. For example, on the web, this would be the browser window size. In a mobile app, it would be the device screen size.

width

number

The width of the visible area, in pixels.

height

number

The height of the visible area, in pixels.

Payload examples

Below are some payload examples for this event:

{  "type": "userScrolled",  "start": {    "x": 0,    "y": 150  },  "end": {    "x": 0,    "y": 780  },  "surfaceSize": {    "width": 1920,    "height": 5400  },  "viewportSize": {    "width": 1920,    "height": 1080  }}