Hierarchical category index navigational system

1. A non-transitory computer-readable medium tangibly embodying computer executable instructions comprising instructions that when executed by a processor cause the processor to:

determine a map control that includes a map interface presenting a map for user interaction has been received;

determine an indication of a first geographical area of interest has been received;

output a first list of items and an icon to be displayed on the map for each item in the first list, wherein the first list of items is associated with a category of interest and wherein each icon is represented at a location on the map interface that presents the geographic location of the item;

automatically request a second list of items if the first geographical area is changed to a second geographical area of interest, the second list of items including items in the category of interest that are also in the second geographical area of interest;

output an icon stack to be displayed on the map if two or more items share a geographic location; and

output an overlay box for display on the map, the overlay box being configured to display in the overlay box at least two items that share the geographic location, the overlay box being configured to adapt the number of pages of the overlay box based on the number of items associated with the icon stack.

2. The computer-readable medium of claim 1 , wherein the second list of items is automatically submitted upon receipt of an indication that the first geographical area of interest has changed to the second geographical area of interest.

3. The computer-readable medium of claim 2 , the instructions further causing the processor to receive the indication from a user input provided to the map control.

4. The computer-readable medium of claim 1 , the instructions further causing the processor to determine whether two or more items share the geographic location based on at least one of a street address and geo-coordinate of each item.

5. The computer-readable medium of claim 1 , the instructions further causing the processor to determine if two or more items share the geographic location based on whether icons representing the two or more items overlap when displayed on the map and independent of at least one of a street address and a geo-coordinate of each item.

6. The computer-readable medium of claim 5 , the instructions further causing the processor to determine whether the icons overlap based on whether the icons have common pixels when displayed on the map.

7. The computer-readable medium of claim 5 , the instructions further causing the processor to:

determine a center point of each icon displayed on the map; and

for each icon displayed, determine a virtual reference circle having a radius defined by a distance between the center point of the icon and a point of the icon furthest from the center point, wherein the processor determines that two items overlap if the virtual reference circle for the two items overlap.

8. The computer-readable medium of claim 7 , the instructions further causing the processor to determine whether the icons overlap based on whether the virtual reference circles of two or more icons overlap.

9. The computer-readable medium of claim 1 , the instructions further causing the processor to output at least one icon stack for display on the map, wherein at least one icon is common to each icon stack.

10. The computer readable medium of claim 1 , the instructions further causing the processor to output the overlay box for display on the map in response to a user input.

11. A system comprising:

a server device configured to provide an indication of a first geographical area of interest and a map control that includes a map interface presenting a map for user interaction;

a client device configured to receive the indication of the first geographical area of interest and the map control, provide a first list of items along with an icon on the map for each item in the first list, wherein the first list of items is associated with a category of interest and wherein each icon is presented at a location on the map interface that represents the geographic location of the item,

wherein the client device is configured to receive a second list of items from the server device if the first geographical area of interest is changed to a second geographical area of interest, the second list of items including items in the category of interest that are also in the second geographical area of interest; and

wherein the client device is configured to output an icon stack if two or more items share a geographic location; and present the icon stack via an overlay box on the map, the overlay box being configured to display in the overlay box at least two items that share the geographic location, the overlay box being configured to adapt the number of pages of the overlay box based on the number of items associated with the icon stack.

12. The system of claim 11 , wherein the client device is configured to automatically request the second list of items from the server device upon receipt of an indication that the first geographical area of interest has changed to the second geographical area of interest, wherein the indication is received by the client device from a user input provided to the map control.

13. The system of claim 11 , wherein the client device is configured to generate the icon stack in response to a user input.

14. The system of claim 13 , wherein the client device is configured to determine whether two or more items share the geographic location based at least in part on whether icons representing the two or more items have common pixels when displayed on the map.

15. The system of claim 13 , wherein the client device is configured to:

determine a center point of each icon displayed on the map;

for each icon displayed, determine a virtual reference circle having a radius defined by a distance between the center point of the icon and a point of the icon furthest from the center point;

determine whether the icons overlap based on whether the virtual reference circles of two or more icons overlap; and

generate the icon stack to include the icons that overlap.

16. The system of claim 13 , wherein the client device is configured to generate more than one icon stack, wherein at least one icon is common to each icon stack.

17. A method comprising:

receiving a map control that includes a map interface presenting a map for user interaction;

receiving an indication of a first geographical area of interest;

providing a first list of items along with an icon on the map for each item in the first list, wherein the first list of items is associated with a category of interest and wherein each icon is represented at a location on the map interface that presents the geographic location of the item;

automatically requesting a second list of items if the first geographical area is changed to a second geographical area of interest, the second list of items including items in the category of interest that are also in the second geographical area of interest, wherein the second list of items is automatically requested upon receipt of a user input provided to the map control that the first geographical area of interest has changed to the second geographical area of interest; and

determining whether two or more items share a geographic location based at least in part on whether icons representing the two or more items overlap on the map;

presenting an icon stack on the map if two or more icons overlap; and

outputting an overlay box on the map, the overlay box is configured to display in the overlay box at least two items that share the geographic location, the overlay box being configured to adapt the number of pages of the overlay box based on the number of items associated with the icon stack.

18. The method of claim 17 , wherein determining whether the icons overlap is based at least in part on whether the icons have common pixels when displayed on the map.

19. The method of claim 17 , wherein determining whether the icons overlap includes:

determining a center point of each icon displayed on the map;

for each icon displayed, determining a virtual reference circle having a radius defined by a distance between the center point of the icon and a point of the icon furthest from the center; and

determining whether the icons overlap based on whether the virtual reference circles of two or more icons overlap.

20. The method of claim 17 , wherein outputting the overlay box is in response to a second user input.