Touch
The Touch sensor responds to Touch events. Touch events offer the ability to interpret finger or stylus activity on touch screens or trackpads.
The touch activator is the
onTouchStart event handler. The Touch sensor is initialized if the there is no more than a single touch on the event.touches property.- Distance constraint
- Delay constraint
These activation constraints are mutually exclusive and may not be used simultaneously.
The distance constraint subscribes to the following interface:
interface DistanceConstraint {
distance: number;
}
The
distance property represents the distance, in pixels, by which the touch input needs to be moved before a drag start event is emitted.The delay constraint subscribe to the following interface:
interface DelayConstraint {
delay: number;
tolerance: number;
}
The
delay property represents the duration, in milliseconds, that a draggable item needs to be held by the touch input before a drag start event is emitted. The
tolerance property represents the distance, in pixels, of motion that is tolerated before the drag operation is aborted. If the finger or stylus is moved during the delay duration and the tolerance is set to zero, the drag operation will be immediately aborted. If a higher tolerance is set, for example, a tolerance of 5 pixels, the operation will only be aborted if the finger is moved by more than 5 pixels during the delay.This property is particularly useful for touch input, where some tolerance should be accounted for when using a delay constraint, as touch input is less precise than mouse input.
We highly recommend you specify the
touch-action CSS property for all of your draggable elements.Thetouch-actionCSS property sets how an element's region can be manipulated by a touchscreen user (for example, by zooming features built into the browser). Source: MDN
In general, we recommend you set the
touch-action property to manipulation for draggable elements when using the Touch sensor. Touch events do not suffer the same limitations as Pointer events, and it is possible to prevent the page from scrolling in
touchmove events.Last modified 2yr ago