Force Touch events

Force Touch events are a proprietary, Apple-specific feature which makes possible (where supported by the input hardware) new interactions based on how hard the user clicks or presses down on the touchscreen or trackpad.

webkitmouseforcewillbegin

This event is fired before the mousedown event. Its main use is that it can be Event.preventDefault()ed.

webkitmouseforcedown

This event is fired after the mousedown event as soon as sufficient pressure has been applied for it to qualify as a "force click".

webkitmouseforceup

This event is fired after the webkitmouseforcedown event as soon as the pressure has been reduced sufficiently to end the "force click".

webkitmouseforcechanged

This event is fired each time the amount of pressure changes. This event first fires after the mousedown event and stops firing before the mouseup event.

The following property is known to be available on the webkitmouseforcewillbegin, mousedown, webkitmouseforcechanged, webkitmouseforcedown, webkitmouseforceup, mousemove, and mouseup event objects:

MouseEvent.webkitForce 只读

当前施加于触控板/触摸屏的压力量

这些常数对于确定由MouseEvent.webkitForce指示的压力的相对强度是有用的：

MouseEvent.WEBKIT_FORCE_AT_MOUSE_DOWN 只读

正常点击所需的最小力量

MouseEvent.WEBKIT_FORCE_AT_FORCE_MOUSE_DOWN 只读

强制点击所需的最小力量

不是任何规格的一部分。苹果在Mac开发者图书馆有一个描述。