ScaleUpdateEvent 继承自： Event[EventControlType]

Continuous payload for scale, pan, and rotation updates.

属性

名称	类型	默认值	说明
local_focal_point	Offset	metadata={'data_field': 'lfp'}	The focal point of the pointers in contact with the screen, in local coordinates.
global_focal_point	Offset	metadata={'data_field': 'gfp'}	The focal point of the pointers in contact with the screen, in global coordinates.
focal_point_delta	Offset	metadata={'data_field': 'fpd'}	The amount the gesture's focal point has moved in the coordinate space of the event receiver since the previous update.
pointer_count	int	metadata={'data_field': 'pc'}	The number of pointers being tracked by the gesture recognizer. Typically this is the number of fingers being used to pan the widget using the gesture recognizer. Due to platform limitations, trackpad gestures count as two fingers even if more than two fingers are used.
horizontal_scale	float	metadata={'data_field': 'hs'}	The scale implied by the average distance along the horizontal axis between the pointers in contact with the screen. This value must be greater than or equal to zero.
vertical_scale	float	metadata={'data_field': 'vs'}	The scale implied by the average distance along the vertical axis between the pointers in contact with the screen. This value must be greater than or equal to zero.
scale	float	metadata={'data_field': 's'}	The scale implied by the average distance between the pointers in contact with the screen. This value must be greater than or equal to zero.
rotation	float	metadata={'data_field': 'rot'}	The angle (in radians) implied by the first two pointers to enter in contact with the screen.
timestamp	Optional[Duration]	None	Recorded timestamp of the source pointer event that triggered the scale event. Could be None if triggered from proxied events such as accessibility.