Extent Indicator is a way to show the extent of one data frame within another data frame. Hard to understand? Let’s try to explain it better:
When you are creating a map, it is often necessary or more interesting to add a new data frame to show in a mini map where the main map is located. For example, if I am showing a municipality on the main map, then in the mini map I show the entire state and highlight the location of that municipality.
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| Source: Esri Help for ArcGIS 10.1 |
Sometimes the area you show on your map (primary or main map) does not have a generally recognized boundary. To provide spatial context for the map reader, you may want to create a locator map. A locator map shows a larger area than the main map. This larger extent should be recognizable to the map reader. A good locator map also contains an indicator, such as a red outline, showing that the extent of the main map fits within this larger extent. For example, the locator map may show the location of a state (extent of the main map) within a country (locator map extent).
How to do it?
Let’s assume you already have the two data frames with the data loaded as above.
- To activate the Extent Indicator, right-click on the mini map, choose properties.
- Go to the tab Extent Indicator
- Move the main data frame to the field “Show extent indicator for these data frames “,
- Click the “Frame” button to choose formatting options.
- Check “Simple Context” if you want only a red box to appear, uncheck it to show the outline as in the example image above.
- Click OK. Done.
Tip: Try using this in conjunction with Data Drive Pages, already explained here (Click) and see the amazing results obtained.