The side of the popover that the arrow should appear on. Corresponds to the edge of the popover closest to the anchor.
'top'
'bottom'
'left'
'right'
The side of the popover that the arrow should appear on. Corresponds to the edge of the popover closest to the anchor.
'top'— arrow on top edge (popover is below the anchor)'bottom'— arrow on bottom edge (popover is above the anchor)'left'— arrow on left edge (popover is to the right of the anchor)'right'— arrow on right edge (popover is to the left of the anchor)