TouchEvent: changedTouches property

{{ APIRef("Touch Events") }}

The changedTouches read-only property is a {{ domxref("TouchList") }} whose touch points ({{domxref("Touch")}} objects) varies depending on the event type, as follows:

• For the {{domxref("Element/touchstart_event", "touchstart")}} event, it is a list of the touch points that became active with the current event.
• For the {{domxref("Element/touchmove_event", "touchmove")}} event, it is a list of the touch points that have changed since the last event.
• For the {{domxref("Element/touchend_event", "touchend")}} and {{domxref("Element/touchcancel_event", "touchcancel")}} events, it is a list of the touch points that have been removed from the surface (that is, the set of touch points corresponding to fingers no longer touching the surface).

Value

A {{ domxref("TouchList") }} whose {{ domxref("Touch") }} objects include all the touch points that contributed to this touch event.

Examples

This example illustrates the {{domxref("TouchEvent")}} object's TouchEvent.changedTouches property. The TouchEvent.changedTouches property is a {{domxref("TouchList")}} object that contains one {{domxref("Touch")}} object for each touch point which contributed to the event.

In following code snippet, the {{domxref("Element/touchmove_event", "touchmove")}} event handler iterates through the changedTouches list and prints the identifier of each touch point that changed since the last event.

someElement.addEventListener("touchmove", (e) => {
  // Iterate through the list of touch points that changed
  // since the last event and print each touch point's identifier.
  for (let i = 0; i < e.changedTouches.length; i++) {
    console.log(
      `changedTouches[${i}].identifier = ${e.changedTouches[i].identifier}`,
    );
  }
});

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}