Drag the blue dot on the right side of the range circle to see
drag effect, and the hit geo will be highlighted after dragend.
Click the options in setCenter and setRadius in toolbar to see
the effect of trigger manual API setting parameters.

拖动范围圆圈右侧的蓝色小点查看拖拽效果，放开后被命中的图形
会高亮。
点击左上角toolbar的setCenter和setRadius中的选项查看手动API
设置参数的效果。