MapView is a toolset within DDA_ACS to facilitate viewing of geographic locations and relationships. MapView is a variation of the ProximityOne CommunityViewer GIS software (http://proximityone.com/cv.htm).
It is difficult to select and use census tract and block group level data without the aid of maps. There is no practical way to view tracts and BGs in the form of hard copy maps. Most users require the flexibility of a GIS application as provided by MapView.
MapView is an integrated part of DDA_ACS but runs independently. With DDA_ACS running, start MapView from the main menu using MapView>Open.
Start MapView and Default GIS Project Opens
With DDA_ACS running, click File>MapView>Open.
MapView starts and displays default project (set default project name in MapView>Settings).
DC1 GIS Project (included with setup)
DC2 GIS Project (included with setup)
The following view shows MapView operations. This view shows two layers, census tracts and block groups, for Honolulu County, Hawaii. Census tracts (layer tl_2010_15tract10.shp) are shown with red boundary with census tract code labels. Block groups (layer tl_2010_15bg10m.shp) are shown with transparent fill pattern and gray boundaries with no label.
The identify tool (pointer) is used to click on a block group (active layer highlighted in legend at left) to display a mini-profile. The profile displays all fields/values for the selected block group shapefile record.
When MapView starts, there are no shapefiles shown in the legend panel and no map is shown in the viewer window.
To view a map, the shapefiles must be opened/added. No shapefiles are provided with the installer. Shapefiles may be downloaded using the File>Get GeoFile Web operation as shown below.
The sequence of steps to view maps is ...
1) obtain shapefiles
- download shapefile
- extract shapefile from downloaded zip file
Item 1) might be performed many times (different shapefiles) but once the shapefiles are on your computer, this step does not need to be repeated. Normally the state by census tract and state by block group shapefiles are needed. Other shapefiles might be useful depending on specific requirements.
2) Use the shapefiles in the Viewer
- add shapefiles to the Viewer
- set attributes of the shapefile to meet specific needs.
When File>Get GeoFile Web is clicked, the shapefile Selection Form appears:
Click in the Click to Select State dropdown, selecting the state of interest. The active state is then shown in the Selected State editbox. The state selection is not relevant/used when selecting a national scale shapefile.
Next select the type of shapefile by clicking a radiobutton in the Type of GeoFile section.
When the Go button is clicked, a download setup is created for the selected type of shapefile for the selected state. A summary of the download is then shown. The process may be optionally canceled.
Note that the shapefile zip file is always downloaded to c:\acs\data\shapefile.zip. Subsequent downloads will overwrite this file.
Unzip the Shapefile
Messages are shown indicating that the shapefile has been downloaded. UnZip the shapefile.zip using the File>Zip/UnZip operation.
The Zip/UnZip form appears. Click Open Zip File and select c:\acs\data\shapefile.zip.
Click Select All button to select/expand all files in the zip. The xml file is not needed and can create confusion in adding shapefiles to the MapView.
Click Unzip button to unzip the selected file which are always placed in the folder c:\acs\data.
Download and extract other shapefiles as desired.
Adding and Using Shapefiles in the Viewer
Open state census tracts shapefile.
Use File>Open to open a state by census tracts shapefile.
The initial view shows the "full extent" of the shapefile.
Select the Zoom tool and zoom to an area of interest:
Use the Add button to add the state by block groups layer.