Android MapView ItemizedOverlay绘制onTap

    protected boolean hitTest(OverlayItem item, Drawable marker, int hitX, int hitY) {
            Point eventPos = new Point(hitX, hitY);
            Point itemHitPosOnDisplay = calculateItemPostionRelativeToDisplay(item.getPoint());
            Point distance = Point.substract(eventPos, itemHitPosOnDisplay);
            if (marker == null) {
                    marker = this.defaultMarker;
            }
            if (Math.abs(distance.x) < marker.getIntrinsicWidth() / 2
                            && Math.abs(distance.y) < marker.getIntrinsicHeight() / 2) {
                    return true;
            }
            return false;
    }