Fires as long as the user is dragging the chart using the mouse or swipe gestures.
A hastable containing the suggested current range (min and max values) of named axes. The axis name is used as a key.
Note that the axis ranges are not updated automatically. You need to call set_options with either the suggested or custom min/max values for them to take effect.
The original user event that triggered the drag action.
The widget instance which fired the event.